1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
3338
3339
3340
3341
3342
3343
3344
3345
3346
3347
3348
3349
3350
3351
3352
3353
3354
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
3370
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
3384
3385
3386
3387
3388
3389
3390
3391
3392
3393
3394
3395
3396
3397
3398
3399
3400
3401
3402
3403
3404
3405
3406
3407
3408
3409
3410
3411
3412
3413
3414
3415
3416
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
3428
3429
3430
3431
3432
3433
3434
3435
3436
3437
3438
3439
3440
3441
3442
3443
3444
3445
3446
3447
3448
3449
3450
3451
3452
3453
3454
3455
3456
3457
3458
3459
3460
3461
3462
3463
3464
3465
3466
3467
3468
3469
3470
3471
3472
3473
3474
3475
3476
3477
3478
3479
3480
3481
3482
3483
3484
3485
3486
3487
3488
3489
3490
3491
3492
3493
3494
3495
3496
3497
3498
3499
3500
3501
3502
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
3527
3528
3529
3530
3531
3532
3533
3534
3535
3536
3537
3538
3539
3540
3541
3542
3543
3544
3545
3546
3547
3548
3549
3550
3551
3552
3553
3554
3555
3556
3557
3558
3559
3560
3561
3562
3563
3564
3565
3566
3567
3568
3569
3570
3571
3572
3573
3574
3575
3576
3577
3578
3579
3580
3581
3582
3583
3584
3585
3586
3587
3588
3589
3590
3591
3592
3593
3594
3595
3596
3597
3598
3599
3600
3601
3602
3603
3604
3605
3606
3607
3608
3609
3610
3611
3612
3613
3614
3615
3616
3617
3618
3619
3620
3621
3622
3623
3624
3625
3626
3627
3628
3629
3630
3631
3632
3633
3634
3635
3636
3637
3638
3639
3640
3641
3642
3643
3644
3645
3646
3647
3648
3649
3650
3651
3652
3653
3654
3655
3656
3657
3658
3659
3660
3661
3662
3663
3664
3665
3666
3667
3668
3669
3670
3671
3672
3673
3674
3675
3676
3677
3678
3679
3680
3681
3682
3683
3684
3685
3686
3687
3688
3689
3690
3691
3692
3693
3694
3695
3696
3697
3698
3699
3700
3701
3702
3703
3704
3705
3706
3707
3708
3709
3710
3711
3712
3713
3714
3715
3716
3717
3718
3719
3720
3721
3722
3723
3724
3725
3726
3727
3728
3729
3730
3731
3732
3733
3734
3735
3736
3737
3738
3739
3740
3741
3742
3743
3744
3745
3746
3747
3748
3749
3750
3751
3752
3753
3754
3755
3756
3757
3758
3759
3760
3761
3762
3763
3764
3765
3766
3767
3768
3769
3770
3771
3772
3773
3774
3775
3776
3777
3778
3779
3780
3781
3782
3783
3784
3785
3786
3787
3788
3789
3790
3791
3792
3793
3794
3795
3796
3797
3798
3799
3800
3801
3802
3803
3804
3805
3806
3807
3808
3809
3810
3811
3812
3813
3814
3815
3816
3817
3818
3819
3820
3821
3822
3823
3824
3825
3826
3827
3828
3829
3830
3831
3832
3833
3834
3835
3836
3837
3838
3839
3840
3841
3842
3843
3844
3845
3846
3847
3848
3849
3850
3851
3852
3853
3854
3855
3856
3857
3858
3859
3860
3861
3862
3863
3864
3865
3866
3867
3868
3869
3870
3871
3872
3873
3874
3875
3876
3877
3878
3879
3880
3881
3882
3883
3884
3885
3886
3887
3888
3889
3890
3891
3892
3893
3894
3895
3896
3897
3898
3899
3900
3901
3902
3903
3904
3905
3906
3907
3908
3909
3910
3911
3912
3913
3914
3915
3916
3917
3918
3919
3920
3921
3922
3923
3924
3925
3926
3927
3928
3929
3930
3931
3932
3933
3934
3935
3936
3937
3938
3939
3940
3941
3942
3943
3944
3945
3946
3947
3948
3949
3950
3951
3952
3953
3954
3955
3956
3957
3958
3959
3960
3961
3962
3963
3964
3965
3966
3967
3968
3969
3970
3971
3972
3973
3974
3975
3976
3977
3978
3979
3980
3981
3982
3983
3984
3985
3986
3987
3988
3989
3990
3991
3992
3993
3994
3995
3996
3997
3998
3999
4000
4001
4002
4003
4004
4005
4006
4007
4008
4009
4010
4011
4012
4013
4014
4015
4016
4017
4018
4019
4020
4021
4022
4023
4024
4025
4026
4027
4028
4029
4030
4031
4032
4033
4034
4035
4036
4037
4038
4039
4040
4041
4042
4043
4044
4045
4046
4047
4048
4049
4050
4051
4052
4053
4054
4055
4056
4057
4058
4059
4060
4061
4062
4063
4064
4065
4066
4067
4068
4069
4070
4071
4072
4073
4074
4075
4076
4077
4078
4079
4080
4081
4082
4083
4084
4085
4086
4087
4088
4089
4090
4091
4092
4093
4094
4095
4096
4097
4098
4099
4100
4101
4102
4103
4104
4105
4106
4107
4108
4109
4110
4111
4112
4113
4114
4115
4116
4117
4118
4119
4120
4121
4122
4123
4124
4125
4126
4127
4128
4129
4130
4131
4132
4133
4134
4135
4136
4137
4138
4139
4140
4141
4142
4143
4144
4145
4146
4147
4148
4149
4150
4151
4152
4153
4154
4155
4156
4157
4158
4159
4160
4161
4162
4163
4164
4165
4166
4167
4168
4169
4170
4171
4172
4173
4174
4175
4176
4177
4178
4179
4180
4181
4182
4183
4184
4185
4186
4187
4188
4189
4190
4191
4192
4193
4194
4195
4196
4197
4198
4199
4200
4201
4202
4203
4204
4205
4206
4207
4208
4209
4210
4211
4212
4213
4214
4215
4216
4217
4218
4219
4220
4221
4222
4223
4224
4225
4226
4227
4228
4229
4230
4231
4232
4233
4234
4235
4236
4237
4238
4239
4240
4241
4242
4243
4244
4245
4246
4247
4248
4249
4250
4251
4252
4253
4254
4255
4256
4257
4258
4259
4260
4261
4262
4263
4264
4265
4266
4267
4268
4269
4270
4271
4272
4273
4274
4275
4276
4277
4278
4279
4280
4281
4282
4283
4284
4285
4286
4287
4288
4289
4290
4291
4292
4293
4294
4295
4296
4297
4298
4299
4300
4301
4302
4303
4304
4305
4306
4307
4308
4309
4310
4311
4312
4313
4314
4315
4316
4317
4318
4319
4320
4321
4322
4323
4324
4325
4326
4327
4328
4329
4330
4331
4332
4333
4334
4335
4336
4337
4338
4339
4340
4341
4342
4343
4344
4345
4346
4347
4348
4349
4350
4351
4352
4353
4354
4355
4356
4357
4358
4359
4360
4361
4362
4363
4364
4365
4366
4367
4368
4369
4370
4371
4372
4373
4374
4375
4376
4377
4378
4379
4380
4381
4382
4383
4384
4385
4386
4387
4388
4389
4390
4391
4392
4393
4394
4395
4396
4397
4398
4399
4400
4401
4402
4403
4404
4405
4406
4407
4408
4409
4410
4411
4412
4413
4414
4415
4416
4417
4418
4419
4420
4421
4422
4423
4424
4425
4426
4427
4428
4429
4430
4431
4432
4433
4434
4435
4436
4437
4438
4439
4440
4441
4442
4443
4444
4445
4446
4447
4448
4449
4450
4451
4452
4453
4454
4455
4456
4457
4458
4459
4460
4461
4462
4463
4464
4465
4466
4467
4468
4469
4470
4471
4472
4473
4474
4475
4476
4477
4478
4479
4480
4481
4482
4483
4484
4485
4486
4487
4488
4489
4490
4491
4492
4493
4494
4495
4496
4497
4498
4499
4500
4501
4502
4503
4504
4505
4506
4507
4508
4509
4510
4511
4512
4513
4514
4515
4516
4517
4518
4519
4520
4521
4522
4523
4524
4525
4526
4527
4528
4529
4530
4531
4532
4533
4534
4535
4536
4537
4538
4539
4540
4541
4542
4543
4544
4545
4546
4547
4548
4549
4550
4551
4552
4553
4554
4555
4556
4557
4558
4559
4560
4561
4562
4563
4564
4565
4566
4567
4568
4569
4570
4571
4572
4573
4574
4575
4576
4577
4578
4579
4580
4581
4582
4583
4584
4585
4586
4587
4588
4589
4590
4591
4592
4593
4594
4595
4596
4597
4598
4599
4600
4601
4602
4603
4604
4605
4606
4607
4608
4609
4610
4611
4612
4613
4614
4615
4616
4617
4618
4619
4620
4621
4622
4623
4624
4625
4626
4627
4628
4629
4630
4631
4632
4633
4634
4635
4636
4637
4638
4639
4640
4641
4642
4643
4644
4645
4646
4647
4648
4649
4650
4651
4652
4653
4654
4655
4656
4657
4658
4659
4660
4661
4662
4663
4664
4665
4666
4667
4668
4669
4670
4671
4672
4673
4674
4675
4676
4677
4678
4679
4680
4681
4682
4683
4684
4685
4686
4687
4688
4689
4690
4691
4692
4693
4694
4695
4696
4697
4698
4699
4700
4701
4702
4703
4704
4705
4706
4707
4708
4709
4710
4711
4712
4713
4714
4715
4716
4717
4718
4719
4720
4721
4722
4723
4724
4725
4726
4727
4728
4729
4730
4731
4732
4733
4734
4735
4736
4737
4738
4739
4740
4741
4742
4743
4744
4745
4746
4747
4748
4749
4750
4751
4752
4753
4754
4755
4756
4757
4758
4759
4760
4761
4762
4763
4764
4765
4766
4767
4768
4769
4770
4771
4772
4773
4774
4775
4776
4777
4778
4779
4780
4781
4782
4783
4784
4785
4786
4787
4788
4789
4790
4791
4792
4793
4794
4795
4796
4797
4798
4799
4800
4801
4802
4803
4804
4805
4806
4807
4808
4809
4810
4811
4812
4813
4814
4815
4816
4817
4818
4819
4820
4821
4822
4823
4824
4825
4826
4827
4828
4829
4830
4831
4832
4833
4834
4835
4836
4837
4838
4839
4840
4841
4842
4843
4844
4845
4846
4847
4848
4849
|
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<!-- Created by GNU Texinfo 6.8, https://www.gnu.org/software/texinfo/ -->
<head>
<meta charset="utf-8">
<title>
FFmpeg Formats Documentation
</title>
<meta name="viewport" content="width=device-width,initial-scale=1.0">
<link rel="stylesheet" type="text/css" href="bootstrap.min.css">
<link rel="stylesheet" type="text/css" href="style.min.css">
</head>
<body>
<div class="container">
<h1>
FFmpeg Formats Documentation
</h1>
<div align="center">
</div>
<a name="SEC_Top"></a>
<div class="Contents_element" id="SEC_Contents">
<h2 class="contents-heading">Table of Contents</h2>
<div class="contents">
<ul class="no-bullet">
<li><a id="toc-Description" href="#Description">1 Description</a></li>
<li><a id="toc-Format-Options" href="#Format-Options">2 Format Options</a>
<ul class="no-bullet">
<li><a id="toc-Format-stream-specifiers-1" href="#Format-stream-specifiers-1">2.1 Format stream specifiers</a></li>
</ul></li>
<li><a id="toc-Demuxers" href="#Demuxers">3 Demuxers</a>
<ul class="no-bullet">
<li><a id="toc-aa" href="#aa">3.1 aa</a></li>
<li><a id="toc-aac" href="#aac">3.2 aac</a></li>
<li><a id="toc-apng" href="#apng">3.3 apng</a></li>
<li><a id="toc-asf-1" href="#asf-1">3.4 asf</a></li>
<li><a id="toc-concat-1" href="#concat-1">3.5 concat</a>
<ul class="no-bullet">
<li><a id="toc-Syntax" href="#Syntax">3.5.1 Syntax</a></li>
<li><a id="toc-Options" href="#Options">3.5.2 Options</a></li>
<li><a id="toc-Examples" href="#Examples">3.5.3 Examples</a></li>
</ul></li>
<li><a id="toc-dash-1" href="#dash-1">3.6 dash</a>
<ul class="no-bullet">
<li><a id="toc-Options-1" href="#Options-1">3.6.1 Options</a></li>
</ul></li>
<li><a id="toc-imf" href="#imf">3.7 imf</a></li>
<li><a id="toc-flv_002c-live_005fflv_002c-kux" href="#flv_002c-live_005fflv_002c-kux">3.8 flv, live_flv, kux</a></li>
<li><a id="toc-gif-1" href="#gif-1">3.9 gif</a></li>
<li><a id="toc-hls-1" href="#hls-1">3.10 hls</a></li>
<li><a id="toc-image2-1" href="#image2-1">3.11 image2</a>
<ul class="no-bullet">
<li><a id="toc-Examples-1" href="#Examples-1">3.11.1 Examples</a></li>
</ul></li>
<li><a id="toc-libgme" href="#libgme">3.12 libgme</a></li>
<li><a id="toc-libmodplug" href="#libmodplug">3.13 libmodplug</a></li>
<li><a id="toc-libopenmpt" href="#libopenmpt">3.14 libopenmpt</a></li>
<li><a id="toc-mov_002fmp4_002f3gp" href="#mov_002fmp4_002f3gp">3.15 mov/mp4/3gp</a>
<ul class="no-bullet">
<li><a id="toc-Options-2" href="#Options-2">3.15.1 Options</a></li>
<li><a id="toc-Audible-AAX" href="#Audible-AAX">3.15.2 Audible AAX</a></li>
</ul></li>
<li><a id="toc-mpegts" href="#mpegts">3.16 mpegts</a></li>
<li><a id="toc-mpjpeg" href="#mpjpeg">3.17 mpjpeg</a></li>
<li><a id="toc-rawvideo" href="#rawvideo">3.18 rawvideo</a></li>
<li><a id="toc-sbg" href="#sbg">3.19 sbg</a></li>
<li><a id="toc-tedcaptions" href="#tedcaptions">3.20 tedcaptions</a></li>
<li><a id="toc-vapoursynth" href="#vapoursynth">3.21 vapoursynth</a></li>
</ul></li>
<li><a id="toc-Muxers" href="#Muxers">4 Muxers</a>
<ul class="no-bullet">
<li><a id="toc-a64-1" href="#a64-1">4.1 a64</a></li>
<li><a id="toc-adts-1" href="#adts-1">4.2 adts</a>
<ul class="no-bullet">
<li><a id="toc-Options-3" href="#Options-3">4.2.1 Options</a></li>
</ul></li>
<li><a id="toc-aiff-1" href="#aiff-1">4.3 aiff</a>
<ul class="no-bullet">
<li><a id="toc-Options-4" href="#Options-4">4.3.1 Options</a></li>
</ul></li>
<li><a id="toc-alp-1" href="#alp-1">4.4 alp</a>
<ul class="no-bullet">
<li><a id="toc-Options-5" href="#Options-5">4.4.1 Options</a></li>
</ul></li>
<li><a id="toc-asf-2" href="#asf-2">4.5 asf</a>
<ul class="no-bullet">
<li><a id="toc-Options-6" href="#Options-6">4.5.1 Options</a></li>
</ul></li>
<li><a id="toc-avi-1" href="#avi-1">4.6 avi</a>
<ul class="no-bullet">
<li><a id="toc-Options-7" href="#Options-7">4.6.1 Options</a></li>
</ul></li>
<li><a id="toc-chromaprint-1" href="#chromaprint-1">4.7 chromaprint</a>
<ul class="no-bullet">
<li><a id="toc-Options-8" href="#Options-8">4.7.1 Options</a></li>
</ul></li>
<li><a id="toc-crc-1" href="#crc-1">4.8 crc</a>
<ul class="no-bullet">
<li><a id="toc-Examples-2" href="#Examples-2">4.8.1 Examples</a></li>
</ul></li>
<li><a id="toc-dash-2" href="#dash-2">4.9 dash</a></li>
<li><a id="toc-fifo-1" href="#fifo-1">4.10 fifo</a>
<ul class="no-bullet">
<li><a id="toc-Examples-3" href="#Examples-3">4.10.1 Examples</a></li>
</ul></li>
<li><a id="toc-flv" href="#flv">4.11 flv</a></li>
<li><a id="toc-framecrc-1" href="#framecrc-1">4.12 framecrc</a>
<ul class="no-bullet">
<li><a id="toc-Examples-4" href="#Examples-4">4.12.1 Examples</a></li>
</ul></li>
<li><a id="toc-framehash-1" href="#framehash-1">4.13 framehash</a>
<ul class="no-bullet">
<li><a id="toc-Examples-5" href="#Examples-5">4.13.1 Examples</a></li>
</ul></li>
<li><a id="toc-framemd5-1" href="#framemd5-1">4.14 framemd5</a>
<ul class="no-bullet">
<li><a id="toc-Examples-6" href="#Examples-6">4.14.1 Examples</a></li>
</ul></li>
<li><a id="toc-gif-2" href="#gif-2">4.15 gif</a></li>
<li><a id="toc-hash-1" href="#hash-1">4.16 hash</a>
<ul class="no-bullet">
<li><a id="toc-Examples-7" href="#Examples-7">4.16.1 Examples</a></li>
</ul></li>
<li><a id="toc-hls-2" href="#hls-2">4.17 hls</a>
<ul class="no-bullet">
<li><a id="toc-Options-9" href="#Options-9">4.17.1 Options</a></li>
</ul></li>
<li><a id="toc-ico-1" href="#ico-1">4.18 ico</a></li>
<li><a id="toc-image2-2" href="#image2-2">4.19 image2</a>
<ul class="no-bullet">
<li><a id="toc-Options-10" href="#Options-10">4.19.1 Options</a></li>
<li><a id="toc-Examples-8" href="#Examples-8">4.19.2 Examples</a></li>
</ul></li>
<li><a id="toc-matroska" href="#matroska">4.20 matroska</a>
<ul class="no-bullet">
<li><a id="toc-Metadata" href="#Metadata">4.20.1 Metadata</a></li>
<li><a id="toc-Options-11" href="#Options-11">4.20.2 Options</a></li>
</ul></li>
<li><a id="toc-md5-1" href="#md5-1">4.21 md5</a>
<ul class="no-bullet">
<li><a id="toc-Examples-9" href="#Examples-9">4.21.1 Examples</a></li>
</ul></li>
<li><a id="toc-mov_002c-mp4_002c-ismv" href="#mov_002c-mp4_002c-ismv">4.22 mov, mp4, ismv</a>
<ul class="no-bullet">
<li><a id="toc-Options-12" href="#Options-12">4.22.1 Options</a></li>
<li><a id="toc-Example" href="#Example">4.22.2 Example</a></li>
</ul></li>
<li><a id="toc-mp3" href="#mp3">4.23 mp3</a></li>
<li><a id="toc-mpegts-1" href="#mpegts-1">4.24 mpegts</a>
<ul class="no-bullet">
<li><a id="toc-Options-13" href="#Options-13">4.24.1 Options</a></li>
<li><a id="toc-Example-1" href="#Example-1">4.24.2 Example</a></li>
</ul></li>
<li><a id="toc-mxf_002c-mxf_005fd10_002c-mxf_005fopatom" href="#mxf_002c-mxf_005fd10_002c-mxf_005fopatom">4.25 mxf, mxf_d10, mxf_opatom</a>
<ul class="no-bullet">
<li><a id="toc-Options-14" href="#Options-14">4.25.1 Options</a></li>
</ul></li>
<li><a id="toc-null" href="#null">4.26 null</a></li>
<li><a id="toc-nut" href="#nut">4.27 nut</a></li>
<li><a id="toc-ogg" href="#ogg">4.28 ogg</a></li>
<li><a id="toc-raw-muxers-1" href="#raw-muxers-1">4.29 raw muxers</a>
<ul class="no-bullet">
<li><a id="toc-ac3" href="#ac3">4.29.1 ac3</a></li>
<li><a id="toc-adx" href="#adx">4.29.2 adx</a></li>
<li><a id="toc-aptx" href="#aptx">4.29.3 aptx</a></li>
<li><a id="toc-aptx_005fhd" href="#aptx_005fhd">4.29.4 aptx_hd</a></li>
<li><a id="toc-avs2" href="#avs2">4.29.5 avs2</a></li>
<li><a id="toc-cavsvideo" href="#cavsvideo">4.29.6 cavsvideo</a></li>
<li><a id="toc-codec2raw" href="#codec2raw">4.29.7 codec2raw</a></li>
<li><a id="toc-data" href="#data">4.29.8 data</a></li>
<li><a id="toc-dirac" href="#dirac">4.29.9 dirac</a></li>
<li><a id="toc-dnxhd" href="#dnxhd">4.29.10 dnxhd</a></li>
<li><a id="toc-dts" href="#dts">4.29.11 dts</a></li>
<li><a id="toc-eac3" href="#eac3">4.29.12 eac3</a></li>
<li><a id="toc-g722" href="#g722">4.29.13 g722</a></li>
<li><a id="toc-g723_005f1" href="#g723_005f1">4.29.14 g723_1</a></li>
<li><a id="toc-g726" href="#g726">4.29.15 g726</a></li>
<li><a id="toc-g726le" href="#g726le">4.29.16 g726le</a></li>
<li><a id="toc-gsm" href="#gsm">4.29.17 gsm</a></li>
<li><a id="toc-h261" href="#h261">4.29.18 h261</a></li>
<li><a id="toc-h263" href="#h263">4.29.19 h263</a></li>
<li><a id="toc-h264" href="#h264">4.29.20 h264</a></li>
<li><a id="toc-hevc" href="#hevc">4.29.21 hevc</a></li>
<li><a id="toc-m4v" href="#m4v">4.29.22 m4v</a></li>
<li><a id="toc-mjpeg" href="#mjpeg">4.29.23 mjpeg</a></li>
<li><a id="toc-mlp" href="#mlp">4.29.24 mlp</a></li>
<li><a id="toc-mp2" href="#mp2">4.29.25 mp2</a></li>
<li><a id="toc-mpeg1video" href="#mpeg1video">4.29.26 mpeg1video</a></li>
<li><a id="toc-mpeg2video" href="#mpeg2video">4.29.27 mpeg2video</a></li>
<li><a id="toc-obu" href="#obu">4.29.28 obu</a></li>
<li><a id="toc-rawvideo-1" href="#rawvideo-1">4.29.29 rawvideo</a></li>
<li><a id="toc-sbc" href="#sbc">4.29.30 sbc</a></li>
<li><a id="toc-truehd" href="#truehd">4.29.31 truehd</a></li>
<li><a id="toc-vc1" href="#vc1">4.29.32 vc1</a></li>
</ul></li>
<li><a id="toc-segment_002c-stream_005fsegment_002c-ssegment" href="#segment_002c-stream_005fsegment_002c-ssegment">4.30 segment, stream_segment, ssegment</a>
<ul class="no-bullet">
<li><a id="toc-Options-15" href="#Options-15">4.30.1 Options</a></li>
<li><a id="toc-Examples-10" href="#Examples-10">4.30.2 Examples</a></li>
</ul></li>
<li><a id="toc-smoothstreaming" href="#smoothstreaming">4.31 smoothstreaming</a></li>
<li><a id="toc-streamhash-1" href="#streamhash-1">4.32 streamhash</a>
<ul class="no-bullet">
<li><a id="toc-Examples-11" href="#Examples-11">4.32.1 Examples</a></li>
</ul></li>
<li><a id="toc-tee-1" href="#tee-1">4.33 tee</a>
<ul class="no-bullet">
<li><a id="toc-Options-16" href="#Options-16">4.33.1 Options</a></li>
<li><a id="toc-Examples-12" href="#Examples-12">4.33.2 Examples</a></li>
</ul></li>
<li><a id="toc-webm_005fchunk" href="#webm_005fchunk">4.34 webm_chunk</a>
<ul class="no-bullet">
<li><a id="toc-Options-17" href="#Options-17">4.34.1 Options</a></li>
<li><a id="toc-Example-2" href="#Example-2">4.34.2 Example</a></li>
</ul></li>
<li><a id="toc-webm_005fdash_005fmanifest" href="#webm_005fdash_005fmanifest">4.35 webm_dash_manifest</a>
<ul class="no-bullet">
<li><a id="toc-Options-18" href="#Options-18">4.35.1 Options</a></li>
<li><a id="toc-Example-3" href="#Example-3">4.35.2 Example</a></li>
</ul></li>
</ul></li>
<li><a id="toc-Metadata-1" href="#Metadata-1">5 Metadata</a></li>
<li><a id="toc-See-Also" href="#See-Also">6 See Also</a></li>
<li><a id="toc-Authors" href="#Authors">7 Authors</a></li>
</ul>
</div>
</div>
<a name="Description"></a>
<h2 class="chapter">1 Description<span class="pull-right"><a class="anchor hidden-xs" href="#Description" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Description" aria-hidden="true">TOC</a></span></h2>
<p>This document describes the supported formats (muxers and demuxers)
provided by the libavformat library.
</p>
<a name="Format-Options"></a>
<h2 class="chapter">2 Format Options<span class="pull-right"><a class="anchor hidden-xs" href="#Format-Options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Format-Options" aria-hidden="true">TOC</a></span></h2>
<p>The libavformat library provides some generic global options, which
can be set on all the muxers and demuxers. In addition each muxer or
demuxer may support so-called private options, which are specific for
that component.
</p>
<p>Options may be set by specifying -<var>option</var> <var>value</var> in the
FFmpeg tools, or by setting the value explicitly in the
<code>AVFormatContext</code> options or using the <samp>libavutil/opt.h</samp> API
for programmatic use.
</p>
<p>The list of supported options follows:
</p>
<dl compact="compact">
<dt><span><samp>avioflags <var>flags</var> (<em>input/output</em>)</samp></span></dt>
<dd><p>Possible values:
</p><dl compact="compact">
<dt><span>‘<samp>direct</samp>’</span></dt>
<dd><p>Reduce buffering.
</p></dd>
</dl>
</dd>
<dt><span><samp>probesize <var>integer</var> (<em>input</em>)</samp></span></dt>
<dd><p>Set probing size in bytes, i.e. the size of the data to analyze to get
stream information. A higher value will enable detecting more
information in case it is dispersed into the stream, but will increase
latency. Must be an integer not lesser than 32. It is 5000000 by default.
</p>
</dd>
<dt><span><samp>max_probe_packets <var>integer</var> (<em>input</em>)</samp></span></dt>
<dd><p>Set the maximum number of buffered packets when probing a codec.
Default is 2500 packets.
</p>
</dd>
<dt><span><samp>packetsize <var>integer</var> (<em>output</em>)</samp></span></dt>
<dd><p>Set packet size.
</p>
</dd>
<dt><span><samp>fflags <var>flags</var></samp></span></dt>
<dd><p>Set format flags. Some are implemented for a limited number of formats.
</p>
<p>Possible values for input files:
</p><dl compact="compact">
<dt><span>‘<samp>discardcorrupt</samp>’</span></dt>
<dd><p>Discard corrupted packets.
</p></dd>
<dt><span>‘<samp>fastseek</samp>’</span></dt>
<dd><p>Enable fast, but inaccurate seeks for some formats.
</p></dd>
<dt><span>‘<samp>genpts</samp>’</span></dt>
<dd><p>Generate missing PTS if DTS is present.
</p></dd>
<dt><span>‘<samp>igndts</samp>’</span></dt>
<dd><p>Ignore DTS if PTS is set. Inert when nofillin is set.
</p></dd>
<dt><span>‘<samp>ignidx</samp>’</span></dt>
<dd><p>Ignore index.
</p></dd>
<dt><span>‘<samp>nobuffer</samp>’</span></dt>
<dd><p>Reduce the latency introduced by buffering during initial input streams analysis.
</p></dd>
<dt><span>‘<samp>nofillin</samp>’</span></dt>
<dd><p>Do not fill in missing values in packet fields that can be exactly calculated.
</p></dd>
<dt><span>‘<samp>noparse</samp>’</span></dt>
<dd><p>Disable AVParsers, this needs <code>+nofillin</code> too.
</p></dd>
<dt><span>‘<samp>sortdts</samp>’</span></dt>
<dd><p>Try to interleave output packets by DTS. At present, available only for AVIs with an index.
</p></dd>
</dl>
<p>Possible values for output files:
</p><dl compact="compact">
<dt><span>‘<samp>autobsf</samp>’</span></dt>
<dd><p>Automatically apply bitstream filters as required by the output format. Enabled by default.
</p></dd>
<dt><span>‘<samp>bitexact</samp>’</span></dt>
<dd><p>Only write platform-, build- and time-independent data.
This ensures that file and data checksums are reproducible and match between
platforms. Its primary use is for regression testing.
</p></dd>
<dt><span>‘<samp>flush_packets</samp>’</span></dt>
<dd><p>Write out packets immediately.
</p></dd>
<dt><span>‘<samp>shortest</samp>’</span></dt>
<dd><p>Stop muxing at the end of the shortest stream.
It may be needed to increase max_interleave_delta to avoid flushing the longer
streams before EOF.
</p></dd>
</dl>
</dd>
<dt><span><samp>seek2any <var>integer</var> (<em>input</em>)</samp></span></dt>
<dd><p>Allow seeking to non-keyframes on demuxer level when supported if set to 1.
Default is 0.
</p>
</dd>
<dt><span><samp>analyzeduration <var>integer</var> (<em>input</em>)</samp></span></dt>
<dd><p>Specify how many microseconds are analyzed to probe the input. A
higher value will enable detecting more accurate information, but will
increase latency. It defaults to 5,000,000 microseconds = 5 seconds.
</p>
</dd>
<dt><span><samp>cryptokey <var>hexadecimal string</var> (<em>input</em>)</samp></span></dt>
<dd><p>Set decryption key.
</p>
</dd>
<dt><span><samp>indexmem <var>integer</var> (<em>input</em>)</samp></span></dt>
<dd><p>Set max memory used for timestamp index (per stream).
</p>
</dd>
<dt><span><samp>rtbufsize <var>integer</var> (<em>input</em>)</samp></span></dt>
<dd><p>Set max memory used for buffering real-time frames.
</p>
</dd>
<dt><span><samp>fdebug <var>flags</var> (<em>input/output</em>)</samp></span></dt>
<dd><p>Print specific debug info.
</p>
<p>Possible values:
</p><dl compact="compact">
<dt><span>‘<samp>ts</samp>’</span></dt>
</dl>
</dd>
<dt><span><samp>max_delay <var>integer</var> (<em>input/output</em>)</samp></span></dt>
<dd><p>Set maximum muxing or demuxing delay in microseconds.
</p>
</dd>
<dt><span><samp>fpsprobesize <var>integer</var> (<em>input</em>)</samp></span></dt>
<dd><p>Set number of frames used to probe fps.
</p>
</dd>
<dt><span><samp>audio_preload <var>integer</var> (<em>output</em>)</samp></span></dt>
<dd><p>Set microseconds by which audio packets should be interleaved earlier.
</p>
</dd>
<dt><span><samp>chunk_duration <var>integer</var> (<em>output</em>)</samp></span></dt>
<dd><p>Set microseconds for each chunk.
</p>
</dd>
<dt><span><samp>chunk_size <var>integer</var> (<em>output</em>)</samp></span></dt>
<dd><p>Set size in bytes for each chunk.
</p>
</dd>
<dt><span><samp>err_detect, f_err_detect <var>flags</var> (<em>input</em>)</samp></span></dt>
<dd><p>Set error detection flags. <code>f_err_detect</code> is deprecated and
should be used only via the <code>ffmpeg</code> tool.
</p>
<p>Possible values:
</p><dl compact="compact">
<dt><span>‘<samp>crccheck</samp>’</span></dt>
<dd><p>Verify embedded CRCs.
</p></dd>
<dt><span>‘<samp>bitstream</samp>’</span></dt>
<dd><p>Detect bitstream specification deviations.
</p></dd>
<dt><span>‘<samp>buffer</samp>’</span></dt>
<dd><p>Detect improper bitstream length.
</p></dd>
<dt><span>‘<samp>explode</samp>’</span></dt>
<dd><p>Abort decoding on minor error detection.
</p></dd>
<dt><span>‘<samp>careful</samp>’</span></dt>
<dd><p>Consider things that violate the spec and have not been seen in the
wild as errors.
</p></dd>
<dt><span>‘<samp>compliant</samp>’</span></dt>
<dd><p>Consider all spec non compliancies as errors.
</p></dd>
<dt><span>‘<samp>aggressive</samp>’</span></dt>
<dd><p>Consider things that a sane encoder should not do as an error.
</p></dd>
</dl>
</dd>
<dt><span><samp>max_interleave_delta <var>integer</var> (<em>output</em>)</samp></span></dt>
<dd><p>Set maximum buffering duration for interleaving. The duration is
expressed in microseconds, and defaults to 10000000 (10 seconds).
</p>
<p>To ensure all the streams are interleaved correctly, libavformat will
wait until it has at least one packet for each stream before actually
writing any packets to the output file. When some streams are
"sparse" (i.e. there are large gaps between successive packets), this
can result in excessive buffering.
</p>
<p>This field specifies the maximum difference between the timestamps of the
first and the last packet in the muxing queue, above which libavformat
will output a packet regardless of whether it has queued a packet for all
the streams.
</p>
<p>If set to 0, libavformat will continue buffering packets until it has
a packet for each stream, regardless of the maximum timestamp
difference between the buffered packets.
</p>
</dd>
<dt><span><samp>use_wallclock_as_timestamps <var>integer</var> (<em>input</em>)</samp></span></dt>
<dd><p>Use wallclock as timestamps if set to 1. Default is 0.
</p>
</dd>
<dt><span><samp>avoid_negative_ts <var>integer</var> (<em>output</em>)</samp></span></dt>
<dd>
<p>Possible values:
</p><dl compact="compact">
<dt><span>‘<samp>make_non_negative</samp>’</span></dt>
<dd><p>Shift timestamps to make them non-negative.
Also note that this affects only leading negative timestamps, and not
non-monotonic negative timestamps.
</p></dd>
<dt><span>‘<samp>make_zero</samp>’</span></dt>
<dd><p>Shift timestamps so that the first timestamp is 0.
</p></dd>
<dt><span>‘<samp>auto (default)</samp>’</span></dt>
<dd><p>Enables shifting when required by the target format.
</p></dd>
<dt><span>‘<samp>disabled</samp>’</span></dt>
<dd><p>Disables shifting of timestamp.
</p></dd>
</dl>
<p>When shifting is enabled, all output timestamps are shifted by the
same amount. Audio, video, and subtitles desynching and relative
timestamp differences are preserved compared to how they would have
been without shifting.
</p>
</dd>
<dt><span><samp>skip_initial_bytes <var>integer</var> (<em>input</em>)</samp></span></dt>
<dd><p>Set number of bytes to skip before reading header and frames if set to 1.
Default is 0.
</p>
</dd>
<dt><span><samp>correct_ts_overflow <var>integer</var> (<em>input</em>)</samp></span></dt>
<dd><p>Correct single timestamp overflows if set to 1. Default is 1.
</p>
</dd>
<dt><span><samp>flush_packets <var>integer</var> (<em>output</em>)</samp></span></dt>
<dd><p>Flush the underlying I/O stream after each packet. Default is -1 (auto), which
means that the underlying protocol will decide, 1 enables it, and has the
effect of reducing the latency, 0 disables it and may increase IO throughput in
some cases.
</p>
</dd>
<dt><span><samp>output_ts_offset <var>offset</var> (<em>output</em>)</samp></span></dt>
<dd><p>Set the output time offset.
</p>
<p><var>offset</var> must be a time duration specification,
see <a data-manual="ffmpeg-utils" href="ffmpeg-utils.html#time-duration-syntax">(ffmpeg-utils)the Time duration section in the ffmpeg-utils(1) manual</a>.
</p>
<p>The offset is added by the muxer to the output timestamps.
</p>
<p>Specifying a positive offset means that the corresponding streams are
delayed bt the time duration specified in <var>offset</var>. Default value
is <code>0</code> (meaning that no offset is applied).
</p>
</dd>
<dt><span><samp>format_whitelist <var>list</var> (<em>input</em>)</samp></span></dt>
<dd><p>"," separated list of allowed demuxers. By default all are allowed.
</p>
</dd>
<dt><span><samp>dump_separator <var>string</var> (<em>input</em>)</samp></span></dt>
<dd><p>Separator used to separate the fields printed on the command line about the
Stream parameters.
For example, to separate the fields with newlines and indentation:
</p><div class="example">
<pre class="example">ffprobe -dump_separator "
" -i ~/videos/matrixbench_mpeg2.mpg
</pre></div>
</dd>
<dt><span><samp>max_streams <var>integer</var> (<em>input</em>)</samp></span></dt>
<dd><p>Specifies the maximum number of streams. This can be used to reject files that
would require too many resources due to a large number of streams.
</p>
</dd>
<dt><span><samp>skip_estimate_duration_from_pts <var>bool</var> (<em>input</em>)</samp></span></dt>
<dd><p>Skip estimation of input duration when calculated using PTS.
At present, applicable for MPEG-PS and MPEG-TS.
</p>
</dd>
<dt><span><samp>strict, f_strict <var>integer</var> (<em>input/output</em>)</samp></span></dt>
<dd><p>Specify how strictly to follow the standards. <code>f_strict</code> is deprecated and
should be used only via the <code>ffmpeg</code> tool.
</p>
<p>Possible values:
</p><dl compact="compact">
<dt><span>‘<samp>very</samp>’</span></dt>
<dd><p>strictly conform to an older more strict version of the spec or reference software
</p></dd>
<dt><span>‘<samp>strict</samp>’</span></dt>
<dd><p>strictly conform to all the things in the spec no matter what consequences
</p></dd>
<dt><span>‘<samp>normal</samp>’</span></dt>
<dt><span>‘<samp>unofficial</samp>’</span></dt>
<dd><p>allow unofficial extensions
</p></dd>
<dt><span>‘<samp>experimental</samp>’</span></dt>
<dd><p>allow non standardized experimental things, experimental
(unfinished/work in progress/not well tested) decoders and encoders.
Note: experimental decoders can pose a security risk, do not use this for
decoding untrusted input.
</p></dd>
</dl>
</dd>
</dl>
<span id="Format-stream-specifiers"></span><a name="Format-stream-specifiers-1"></a>
<h3 class="section">2.1 Format stream specifiers<span class="pull-right"><a class="anchor hidden-xs" href="#Format-stream-specifiers-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Format-stream-specifiers-1" aria-hidden="true">TOC</a></span></h3>
<p>Format stream specifiers allow selection of one or more streams that
match specific properties.
</p>
<p>The exact semantics of stream specifiers is defined by the
<code>avformat_match_stream_specifier()</code> function declared in the
<samp>libavformat/avformat.h</samp> header and documented in the
<a data-manual="ffmpeg" href="ffmpeg.html#Stream-specifiers">(ffmpeg)Stream specifiers section in the ffmpeg(1) manual</a>.
</p>
<a name="Demuxers"></a>
<h2 class="chapter">3 Demuxers<span class="pull-right"><a class="anchor hidden-xs" href="#Demuxers" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Demuxers" aria-hidden="true">TOC</a></span></h2>
<p>Demuxers are configured elements in FFmpeg that can read the
multimedia streams from a particular type of file.
</p>
<p>When you configure your FFmpeg build, all the supported demuxers
are enabled by default. You can list all available ones using the
configure option <code>--list-demuxers</code>.
</p>
<p>You can disable all the demuxers using the configure option
<code>--disable-demuxers</code>, and selectively enable a single demuxer with
the option <code>--enable-demuxer=<var>DEMUXER</var></code>, or disable it
with the option <code>--disable-demuxer=<var>DEMUXER</var></code>.
</p>
<p>The option <code>-demuxers</code> of the ff* tools will display the list of
enabled demuxers. Use <code>-formats</code> to view a combined list of
enabled demuxers and muxers.
</p>
<p>The description of some of the currently available demuxers follows.
</p>
<a name="aa"></a>
<h3 class="section">3.1 aa<span class="pull-right"><a class="anchor hidden-xs" href="#aa" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-aa" aria-hidden="true">TOC</a></span></h3>
<p>Audible Format 2, 3, and 4 demuxer.
</p>
<p>This demuxer is used to demux Audible Format 2, 3, and 4 (.aa) files.
</p>
<a name="aac"></a>
<h3 class="section">3.2 aac<span class="pull-right"><a class="anchor hidden-xs" href="#aac" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-aac" aria-hidden="true">TOC</a></span></h3>
<p>Raw Audio Data Transport Stream AAC demuxer.
</p>
<p>This demuxer is used to demux an ADTS input containing a single AAC stream
alongwith any ID3v1/2 or APE tags in it.
</p>
<a name="apng"></a>
<h3 class="section">3.3 apng<span class="pull-right"><a class="anchor hidden-xs" href="#apng" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-apng" aria-hidden="true">TOC</a></span></h3>
<p>Animated Portable Network Graphics demuxer.
</p>
<p>This demuxer is used to demux APNG files.
All headers, but the PNG signature, up to (but not including) the first
fcTL chunk are transmitted as extradata.
Frames are then split as being all the chunks between two fcTL ones, or
between the last fcTL and IEND chunks.
</p>
<dl compact="compact">
<dt><span><samp>-ignore_loop <var>bool</var></samp></span></dt>
<dd><p>Ignore the loop variable in the file if set. Default is enabled.
</p>
</dd>
<dt><span><samp>-max_fps <var>int</var></samp></span></dt>
<dd><p>Maximum framerate in frames per second. Default of 0 imposes no limit.
</p>
</dd>
<dt><span><samp>-default_fps <var>int</var></samp></span></dt>
<dd><p>Default framerate in frames per second when none is specified in the file
(0 meaning as fast as possible). Default is 15.
</p>
</dd>
</dl>
<a name="asf-1"></a>
<h3 class="section">3.4 asf<span class="pull-right"><a class="anchor hidden-xs" href="#asf-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-asf-1" aria-hidden="true">TOC</a></span></h3>
<p>Advanced Systems Format demuxer.
</p>
<p>This demuxer is used to demux ASF files and MMS network streams.
</p>
<dl compact="compact">
<dt><span><samp>-no_resync_search <var>bool</var></samp></span></dt>
<dd><p>Do not try to resynchronize by looking for a certain optional start code.
</p></dd>
</dl>
<span id="concat"></span><a name="concat-1"></a>
<h3 class="section">3.5 concat<span class="pull-right"><a class="anchor hidden-xs" href="#concat-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-concat-1" aria-hidden="true">TOC</a></span></h3>
<p>Virtual concatenation script demuxer.
</p>
<p>This demuxer reads a list of files and other directives from a text file and
demuxes them one after the other, as if all their packets had been muxed
together.
</p>
<p>The timestamps in the files are adjusted so that the first file starts at 0
and each next file starts where the previous one finishes. Note that it is
done globally and may cause gaps if all streams do not have exactly the same
length.
</p>
<p>All files must have the same streams (same codecs, same time base, etc.).
</p>
<p>The duration of each file is used to adjust the timestamps of the next file:
if the duration is incorrect (because it was computed using the bit-rate or
because the file is truncated, for example), it can cause artifacts. The
<code>duration</code> directive can be used to override the duration stored in
each file.
</p>
<a name="Syntax"></a>
<h4 class="subsection">3.5.1 Syntax<span class="pull-right"><a class="anchor hidden-xs" href="#Syntax" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Syntax" aria-hidden="true">TOC</a></span></h4>
<p>The script is a text file in extended-ASCII, with one directive per line.
Empty lines, leading spaces and lines starting with ’#’ are ignored. The
following directive is recognized:
</p>
<dl compact="compact">
<dt><span><samp><code>file <var>path</var></code></samp></span></dt>
<dd><p>Path to a file to read; special characters and spaces must be escaped with
backslash or single quotes.
</p>
<p>All subsequent file-related directives apply to that file.
</p>
</dd>
<dt><span><samp><code>ffconcat version 1.0</code></samp></span></dt>
<dd><p>Identify the script type and version.
</p>
<p>To make FFmpeg recognize the format automatically, this directive must
appear exactly as is (no extra space or byte-order-mark) on the very first
line of the script.
</p>
</dd>
<dt><span><samp><code>duration <var>dur</var></code></samp></span></dt>
<dd><p>Duration of the file. This information can be specified from the file;
specifying it here may be more efficient or help if the information from the
file is not available or accurate.
</p>
<p>If the duration is set for all files, then it is possible to seek in the
whole concatenated video.
</p>
</dd>
<dt><span><samp><code>inpoint <var>timestamp</var></code></samp></span></dt>
<dd><p>In point of the file. When the demuxer opens the file it instantly seeks to the
specified timestamp. Seeking is done so that all streams can be presented
successfully at In point.
</p>
<p>This directive works best with intra frame codecs, because for non-intra frame
ones you will usually get extra packets before the actual In point and the
decoded content will most likely contain frames before In point too.
</p>
<p>For each file, packets before the file In point will have timestamps less than
the calculated start timestamp of the file (negative in case of the first
file), and the duration of the files (if not specified by the <code>duration</code>
directive) will be reduced based on their specified In point.
</p>
<p>Because of potential packets before the specified In point, packet timestamps
may overlap between two concatenated files.
</p>
</dd>
<dt><span><samp><code>outpoint <var>timestamp</var></code></samp></span></dt>
<dd><p>Out point of the file. When the demuxer reaches the specified decoding
timestamp in any of the streams, it handles it as an end of file condition and
skips the current and all the remaining packets from all streams.
</p>
<p>Out point is exclusive, which means that the demuxer will not output packets
with a decoding timestamp greater or equal to Out point.
</p>
<p>This directive works best with intra frame codecs and formats where all streams
are tightly interleaved. For non-intra frame codecs you will usually get
additional packets with presentation timestamp after Out point therefore the
decoded content will most likely contain frames after Out point too. If your
streams are not tightly interleaved you may not get all the packets from all
streams before Out point and you may only will be able to decode the earliest
stream until Out point.
</p>
<p>The duration of the files (if not specified by the <code>duration</code>
directive) will be reduced based on their specified Out point.
</p>
</dd>
<dt><span><samp><code>file_packet_metadata <var>key=value</var></code></samp></span></dt>
<dd><p>Metadata of the packets of the file. The specified metadata will be set for
each file packet. You can specify this directive multiple times to add multiple
metadata entries.
This directive is deprecated, use <code>file_packet_meta</code> instead.
</p>
</dd>
<dt><span><samp><code>file_packet_meta <var>key</var> <var>value</var></code></samp></span></dt>
<dd><p>Metadata of the packets of the file. The specified metadata will be set for
each file packet. You can specify this directive multiple times to add multiple
metadata entries.
</p>
</dd>
<dt><span><samp><code>option <var>key</var> <var>value</var></code></samp></span></dt>
<dd><p>Option to access, open and probe the file.
Can be present multiple times.
</p>
</dd>
<dt><span><samp><code>stream</code></samp></span></dt>
<dd><p>Introduce a stream in the virtual file.
All subsequent stream-related directives apply to the last introduced
stream.
Some streams properties must be set in order to allow identifying the
matching streams in the subfiles.
If no streams are defined in the script, the streams from the first file are
copied.
</p>
</dd>
<dt><span><samp><code>exact_stream_id <var>id</var></code></samp></span></dt>
<dd><p>Set the id of the stream.
If this directive is given, the string with the corresponding id in the
subfiles will be used.
This is especially useful for MPEG-PS (VOB) files, where the order of the
streams is not reliable.
</p>
</dd>
<dt><span><samp><code>stream_meta <var>key</var> <var>value</var></code></samp></span></dt>
<dd><p>Metadata for the stream.
Can be present multiple times.
</p>
</dd>
<dt><span><samp><code>stream_codec <var>value</var></code></samp></span></dt>
<dd><p>Codec for the stream.
</p>
</dd>
<dt><span><samp><code>stream_extradata <var>hex_string</var></code></samp></span></dt>
<dd><p>Extradata for the string, encoded in hexadecimal.
</p>
</dd>
<dt><span><samp><code>chapter <var>id</var> <var>start</var> <var>end</var></code></samp></span></dt>
<dd><p>Add a chapter. <var>id</var> is an unique identifier, possibly small and
consecutive.
</p>
</dd>
</dl>
<a name="Options"></a>
<h4 class="subsection">3.5.2 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options" aria-hidden="true">TOC</a></span></h4>
<p>This demuxer accepts the following option:
</p>
<dl compact="compact">
<dt><span><samp>safe</samp></span></dt>
<dd><p>If set to 1, reject unsafe file paths and directives.
A file path is considered safe if it
does not contain a protocol specification and is relative and all components
only contain characters from the portable character set (letters, digits,
period, underscore and hyphen) and have no period at the beginning of a
component.
</p>
<p>If set to 0, any file name is accepted.
</p>
<p>The default is 1.
</p>
</dd>
<dt><span><samp>auto_convert</samp></span></dt>
<dd><p>If set to 1, try to perform automatic conversions on packet data to make the
streams concatenable.
The default is 1.
</p>
<p>Currently, the only conversion is adding the h264_mp4toannexb bitstream
filter to H.264 streams in MP4 format. This is necessary in particular if
there are resolution changes.
</p>
</dd>
<dt><span><samp>segment_time_metadata</samp></span></dt>
<dd><p>If set to 1, every packet will contain the <var>lavf.concat.start_time</var> and the
<var>lavf.concat.duration</var> packet metadata values which are the start_time and
the duration of the respective file segments in the concatenated output
expressed in microseconds. The duration metadata is only set if it is known
based on the concat file.
The default is 0.
</p>
</dd>
</dl>
<a name="Examples"></a>
<h4 class="subsection">3.5.3 Examples<span class="pull-right"><a class="anchor hidden-xs" href="#Examples" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Examples" aria-hidden="true">TOC</a></span></h4>
<ul>
<li> Use absolute filenames and include some comments:
<div class="example">
<pre class="example"># my first filename
file /mnt/share/file-1.wav
# my second filename including whitespace
file '/mnt/share/file 2.wav'
# my third filename including whitespace plus single quote
file '/mnt/share/file 3'\''.wav'
</pre></div>
</li><li> Allow for input format auto-probing, use safe filenames and set the duration of
the first file:
<div class="example">
<pre class="example">ffconcat version 1.0
file file-1.wav
duration 20.0
file subdir/file-2.wav
</pre></div>
</li></ul>
<a name="dash-1"></a>
<h3 class="section">3.6 dash<span class="pull-right"><a class="anchor hidden-xs" href="#dash-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-dash-1" aria-hidden="true">TOC</a></span></h3>
<p>Dynamic Adaptive Streaming over HTTP demuxer.
</p>
<p>This demuxer presents all AVStreams found in the manifest.
By setting the discard flags on AVStreams the caller can decide
which streams to actually receive.
Each stream mirrors the <code>id</code> and <code>bandwidth</code> properties from the
<code><Representation></code> as metadata keys named "id" and "variant_bitrate" respectively.
</p>
<a name="Options-1"></a>
<h4 class="subsection">3.6.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-1" aria-hidden="true">TOC</a></span></h4>
<p>This demuxer accepts the following option:
</p>
<dl compact="compact">
<dt><span><samp>cenc_decryption_key</samp></span></dt>
<dd><p>16-byte key, in hex, to decrypt files encrypted using ISO Common Encryption (CENC/AES-128 CTR; ISO/IEC 23001-7).
</p>
</dd>
</dl>
<a name="imf"></a>
<h3 class="section">3.7 imf<span class="pull-right"><a class="anchor hidden-xs" href="#imf" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-imf" aria-hidden="true">TOC</a></span></h3>
<p>Interoperable Master Format demuxer.
</p>
<p>This demuxer presents audio and video streams found in an IMF Composition.
</p>
<a name="flv_002c-live_005fflv_002c-kux"></a>
<h3 class="section">3.8 flv, live_flv, kux<span class="pull-right"><a class="anchor hidden-xs" href="#flv_002c-live_005fflv_002c-kux" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-flv_002c-live_005fflv_002c-kux" aria-hidden="true">TOC</a></span></h3>
<p>Adobe Flash Video Format demuxer.
</p>
<p>This demuxer is used to demux FLV files and RTMP network streams. In case of live network streams, if you force format, you may use live_flv option instead of flv to survive timestamp discontinuities.
KUX is a flv variant used on the Youku platform.
</p>
<div class="example">
<pre class="example">ffmpeg -f flv -i myfile.flv ...
ffmpeg -f live_flv -i rtmp://<any.server>/anything/key ....
</pre></div>
<dl compact="compact">
<dt><span><samp>-flv_metadata <var>bool</var></samp></span></dt>
<dd><p>Allocate the streams according to the onMetaData array content.
</p>
</dd>
<dt><span><samp>-flv_ignore_prevtag <var>bool</var></samp></span></dt>
<dd><p>Ignore the size of previous tag value.
</p>
</dd>
<dt><span><samp>-flv_full_metadata <var>bool</var></samp></span></dt>
<dd><p>Output all context of the onMetadata.
</p></dd>
</dl>
<a name="gif-1"></a>
<h3 class="section">3.9 gif<span class="pull-right"><a class="anchor hidden-xs" href="#gif-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-gif-1" aria-hidden="true">TOC</a></span></h3>
<p>Animated GIF demuxer.
</p>
<p>It accepts the following options:
</p>
<dl compact="compact">
<dt><span><samp>min_delay</samp></span></dt>
<dd><p>Set the minimum valid delay between frames in hundredths of seconds.
Range is 0 to 6000. Default value is 2.
</p>
</dd>
<dt><span><samp>max_gif_delay</samp></span></dt>
<dd><p>Set the maximum valid delay between frames in hundredth of seconds.
Range is 0 to 65535. Default value is 65535 (nearly eleven minutes),
the maximum value allowed by the specification.
</p>
</dd>
<dt><span><samp>default_delay</samp></span></dt>
<dd><p>Set the default delay between frames in hundredths of seconds.
Range is 0 to 6000. Default value is 10.
</p>
</dd>
<dt><span><samp>ignore_loop</samp></span></dt>
<dd><p>GIF files can contain information to loop a certain number of times (or
infinitely). If <samp>ignore_loop</samp> is set to 1, then the loop setting
from the input will be ignored and looping will not occur. If set to 0,
then looping will occur and will cycle the number of times according to
the GIF. Default value is 1.
</p></dd>
</dl>
<p>For example, with the overlay filter, place an infinitely looping GIF
over another video:
</p><div class="example">
<pre class="example">ffmpeg -i input.mp4 -ignore_loop 0 -i input.gif -filter_complex overlay=shortest=1 out.mkv
</pre></div>
<p>Note that in the above example the shortest option for overlay filter is
used to end the output video at the length of the shortest input file,
which in this case is <samp>input.mp4</samp> as the GIF in this example loops
infinitely.
</p>
<a name="hls-1"></a>
<h3 class="section">3.10 hls<span class="pull-right"><a class="anchor hidden-xs" href="#hls-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-hls-1" aria-hidden="true">TOC</a></span></h3>
<p>HLS demuxer
</p>
<p>Apple HTTP Live Streaming demuxer.
</p>
<p>This demuxer presents all AVStreams from all variant streams.
The id field is set to the bitrate variant index number. By setting
the discard flags on AVStreams (by pressing ’a’ or ’v’ in ffplay),
the caller can decide which variant streams to actually receive.
The total bitrate of the variant that the stream belongs to is
available in a metadata key named "variant_bitrate".
</p>
<p>It accepts the following options:
</p>
<dl compact="compact">
<dt><span><samp>live_start_index</samp></span></dt>
<dd><p>segment index to start live streams at (negative values are from the end).
</p>
</dd>
<dt><span><samp>prefer_x_start</samp></span></dt>
<dd><p>prefer to use #EXT-X-START if it’s in playlist instead of live_start_index.
</p>
</dd>
<dt><span><samp>allowed_extensions</samp></span></dt>
<dd><p>’,’ separated list of file extensions that hls is allowed to access.
</p>
</dd>
<dt><span><samp>max_reload</samp></span></dt>
<dd><p>Maximum number of times a insufficient list is attempted to be reloaded.
Default value is 1000.
</p>
</dd>
<dt><span><samp>m3u8_hold_counters</samp></span></dt>
<dd><p>The maximum number of times to load m3u8 when it refreshes without new segments.
Default value is 1000.
</p>
</dd>
<dt><span><samp>http_persistent</samp></span></dt>
<dd><p>Use persistent HTTP connections. Applicable only for HTTP streams.
Enabled by default.
</p>
</dd>
<dt><span><samp>http_multiple</samp></span></dt>
<dd><p>Use multiple HTTP connections for downloading HTTP segments.
Enabled by default for HTTP/1.1 servers.
</p>
</dd>
<dt><span><samp>http_seekable</samp></span></dt>
<dd><p>Use HTTP partial requests for downloading HTTP segments.
0 = disable, 1 = enable, -1 = auto, Default is auto.
</p>
</dd>
<dt><span><samp>seg_format_options</samp></span></dt>
<dd><p>Set options for the demuxer of media segments using a list of key=value pairs separated by <code>:</code>.
</p></dd>
</dl>
<a name="image2-1"></a>
<h3 class="section">3.11 image2<span class="pull-right"><a class="anchor hidden-xs" href="#image2-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-image2-1" aria-hidden="true">TOC</a></span></h3>
<p>Image file demuxer.
</p>
<p>This demuxer reads from a list of image files specified by a pattern.
The syntax and meaning of the pattern is specified by the
option <var>pattern_type</var>.
</p>
<p>The pattern may contain a suffix which is used to automatically
determine the format of the images contained in the files.
</p>
<p>The size, the pixel format, and the format of each image must be the
same for all the files in the sequence.
</p>
<p>This demuxer accepts the following options:
</p><dl compact="compact">
<dt><span><samp>framerate</samp></span></dt>
<dd><p>Set the frame rate for the video stream. It defaults to 25.
</p></dd>
<dt><span><samp>loop</samp></span></dt>
<dd><p>If set to 1, loop over the input. Default value is 0.
</p></dd>
<dt><span><samp>pattern_type</samp></span></dt>
<dd><p>Select the pattern type used to interpret the provided filename.
</p>
<p><var>pattern_type</var> accepts one of the following values.
</p><dl compact="compact">
<dt><span><samp>none</samp></span></dt>
<dd><p>Disable pattern matching, therefore the video will only contain the specified
image. You should use this option if you do not want to create sequences from
multiple images and your filenames may contain special pattern characters.
</p></dd>
<dt><span><samp>sequence</samp></span></dt>
<dd><p>Select a sequence pattern type, used to specify a sequence of files
indexed by sequential numbers.
</p>
<p>A sequence pattern may contain the string "%d" or "%0<var>N</var>d", which
specifies the position of the characters representing a sequential
number in each filename matched by the pattern. If the form
"%d0<var>N</var>d" is used, the string representing the number in each
filename is 0-padded and <var>N</var> is the total number of 0-padded
digits representing the number. The literal character ’%’ can be
specified in the pattern with the string "%%".
</p>
<p>If the sequence pattern contains "%d" or "%0<var>N</var>d", the first filename of
the file list specified by the pattern must contain a number
inclusively contained between <var>start_number</var> and
<var>start_number</var>+<var>start_number_range</var>-1, and all the following
numbers must be sequential.
</p>
<p>For example the pattern "img-%03d.bmp" will match a sequence of
filenames of the form <samp>img-001.bmp</samp>, <samp>img-002.bmp</samp>, ...,
<samp>img-010.bmp</samp>, etc.; the pattern "i%%m%%g-%d.jpg" will match a
sequence of filenames of the form <samp>i%m%g-1.jpg</samp>,
<samp>i%m%g-2.jpg</samp>, ..., <samp>i%m%g-10.jpg</samp>, etc.
</p>
<p>Note that the pattern must not necessarily contain "%d" or
"%0<var>N</var>d", for example to convert a single image file
<samp>img.jpeg</samp> you can employ the command:
</p><div class="example">
<pre class="example">ffmpeg -i img.jpeg img.png
</pre></div>
</dd>
<dt><span><samp>glob</samp></span></dt>
<dd><p>Select a glob wildcard pattern type.
</p>
<p>The pattern is interpreted like a <code>glob()</code> pattern. This is only
selectable if libavformat was compiled with globbing support.
</p>
</dd>
<dt><span><samp>glob_sequence <em>(deprecated, will be removed)</em></samp></span></dt>
<dd><p>Select a mixed glob wildcard/sequence pattern.
</p>
<p>If your version of libavformat was compiled with globbing support, and
the provided pattern contains at least one glob meta character among
<code>%*?[]{}</code> that is preceded by an unescaped "%", the pattern is
interpreted like a <code>glob()</code> pattern, otherwise it is interpreted
like a sequence pattern.
</p>
<p>All glob special characters <code>%*?[]{}</code> must be prefixed
with "%". To escape a literal "%" you shall use "%%".
</p>
<p>For example the pattern <code>foo-%*.jpeg</code> will match all the
filenames prefixed by "foo-" and terminating with ".jpeg", and
<code>foo-%?%?%?.jpeg</code> will match all the filenames prefixed with
"foo-", followed by a sequence of three characters, and terminating
with ".jpeg".
</p>
<p>This pattern type is deprecated in favor of <var>glob</var> and
<var>sequence</var>.
</p></dd>
</dl>
<p>Default value is <var>glob_sequence</var>.
</p></dd>
<dt><span><samp>pixel_format</samp></span></dt>
<dd><p>Set the pixel format of the images to read. If not specified the pixel
format is guessed from the first image file in the sequence.
</p></dd>
<dt><span><samp>start_number</samp></span></dt>
<dd><p>Set the index of the file matched by the image file pattern to start
to read from. Default value is 0.
</p></dd>
<dt><span><samp>start_number_range</samp></span></dt>
<dd><p>Set the index interval range to check when looking for the first image
file in the sequence, starting from <var>start_number</var>. Default value
is 5.
</p></dd>
<dt><span><samp>ts_from_file</samp></span></dt>
<dd><p>If set to 1, will set frame timestamp to modification time of image file. Note
that monotonity of timestamps is not provided: images go in the same order as
without this option. Default value is 0.
If set to 2, will set frame timestamp to the modification time of the image file in
nanosecond precision.
</p></dd>
<dt><span><samp>video_size</samp></span></dt>
<dd><p>Set the video size of the images to read. If not specified the video
size is guessed from the first image file in the sequence.
</p></dd>
<dt><span><samp>export_path_metadata</samp></span></dt>
<dd><p>If set to 1, will add two extra fields to the metadata found in input, making them
also available for other filters (see <var>drawtext</var> filter for examples). Default
value is 0. The extra fields are described below:
</p><dl compact="compact">
<dt><span><samp>lavf.image2dec.source_path</samp></span></dt>
<dd><p>Corresponds to the full path to the input file being read.
</p></dd>
<dt><span><samp>lavf.image2dec.source_basename</samp></span></dt>
<dd><p>Corresponds to the name of the file being read.
</p></dd>
</dl>
</dd>
</dl>
<a name="Examples-1"></a>
<h4 class="subsection">3.11.1 Examples<span class="pull-right"><a class="anchor hidden-xs" href="#Examples-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Examples-1" aria-hidden="true">TOC</a></span></h4>
<ul>
<li> Use <code>ffmpeg</code> for creating a video from the images in the file
sequence <samp>img-001.jpeg</samp>, <samp>img-002.jpeg</samp>, ..., assuming an
input frame rate of 10 frames per second:
<div class="example">
<pre class="example">ffmpeg -framerate 10 -i 'img-%03d.jpeg' out.mkv
</pre></div>
</li><li> As above, but start by reading from a file with index 100 in the sequence:
<div class="example">
<pre class="example">ffmpeg -framerate 10 -start_number 100 -i 'img-%03d.jpeg' out.mkv
</pre></div>
</li><li> Read images matching the "*.png" glob pattern , that is all the files
terminating with the ".png" suffix:
<div class="example">
<pre class="example">ffmpeg -framerate 10 -pattern_type glob -i "*.png" out.mkv
</pre></div>
</li></ul>
<a name="libgme"></a>
<h3 class="section">3.12 libgme<span class="pull-right"><a class="anchor hidden-xs" href="#libgme" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libgme" aria-hidden="true">TOC</a></span></h3>
<p>The Game Music Emu library is a collection of video game music file emulators.
</p>
<p>See <a href="https://bitbucket.org/mpyne/game-music-emu/overview">https://bitbucket.org/mpyne/game-music-emu/overview</a> for more information.
</p>
<p>It accepts the following options:
</p>
<dl compact="compact">
<dt><span><samp>track_index</samp></span></dt>
<dd><p>Set the index of which track to demux. The demuxer can only export one track.
Track indexes start at 0. Default is to pick the first track. Number of tracks
is exported as <var>tracks</var> metadata entry.
</p>
</dd>
<dt><span><samp>sample_rate</samp></span></dt>
<dd><p>Set the sampling rate of the exported track. Range is 1000 to 999999. Default is 44100.
</p>
</dd>
<dt><span><samp>max_size <em>(bytes)</em></samp></span></dt>
<dd><p>The demuxer buffers the entire file into memory. Adjust this value to set the maximum buffer size,
which in turn, acts as a ceiling for the size of files that can be read.
Default is 50 MiB.
</p>
</dd>
</dl>
<a name="libmodplug"></a>
<h3 class="section">3.13 libmodplug<span class="pull-right"><a class="anchor hidden-xs" href="#libmodplug" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libmodplug" aria-hidden="true">TOC</a></span></h3>
<p>ModPlug based module demuxer
</p>
<p>See <a href="https://github.com/Konstanty/libmodplug">https://github.com/Konstanty/libmodplug</a>
</p>
<p>It will export one 2-channel 16-bit 44.1 kHz audio stream.
Optionally, a <code>pal8</code> 16-color video stream can be exported with or without printed metadata.
</p>
<p>It accepts the following options:
</p>
<dl compact="compact">
<dt><span><samp>noise_reduction</samp></span></dt>
<dd><p>Apply a simple low-pass filter. Can be 1 (on) or 0 (off). Default is 0.
</p>
</dd>
<dt><span><samp>reverb_depth</samp></span></dt>
<dd><p>Set amount of reverb. Range 0-100. Default is 0.
</p>
</dd>
<dt><span><samp>reverb_delay</samp></span></dt>
<dd><p>Set delay in ms, clamped to 40-250 ms. Default is 0.
</p>
</dd>
<dt><span><samp>bass_amount</samp></span></dt>
<dd><p>Apply bass expansion a.k.a. XBass or megabass. Range is 0 (quiet) to 100 (loud). Default is 0.
</p>
</dd>
<dt><span><samp>bass_range</samp></span></dt>
<dd><p>Set cutoff i.e. upper-bound for bass frequencies. Range is 10-100 Hz. Default is 0.
</p>
</dd>
<dt><span><samp>surround_depth</samp></span></dt>
<dd><p>Apply a Dolby Pro-Logic surround effect. Range is 0 (quiet) to 100 (heavy). Default is 0.
</p>
</dd>
<dt><span><samp>surround_delay</samp></span></dt>
<dd><p>Set surround delay in ms, clamped to 5-40 ms. Default is 0.
</p>
</dd>
<dt><span><samp>max_size</samp></span></dt>
<dd><p>The demuxer buffers the entire file into memory. Adjust this value to set the maximum buffer size,
which in turn, acts as a ceiling for the size of files that can be read. Range is 0 to 100 MiB.
0 removes buffer size limit (not recommended). Default is 5 MiB.
</p>
</dd>
<dt><span><samp>video_stream_expr</samp></span></dt>
<dd><p>String which is evaluated using the eval API to assign colors to the generated video stream.
Variables which can be used are <code>x</code>, <code>y</code>, <code>w</code>, <code>h</code>, <code>t</code>, <code>speed</code>,
<code>tempo</code>, <code>order</code>, <code>pattern</code> and <code>row</code>.
</p>
</dd>
<dt><span><samp>video_stream</samp></span></dt>
<dd><p>Generate video stream. Can be 1 (on) or 0 (off). Default is 0.
</p>
</dd>
<dt><span><samp>video_stream_w</samp></span></dt>
<dd><p>Set video frame width in ’chars’ where one char indicates 8 pixels. Range is 20-512. Default is 30.
</p>
</dd>
<dt><span><samp>video_stream_h</samp></span></dt>
<dd><p>Set video frame height in ’chars’ where one char indicates 8 pixels. Range is 20-512. Default is 30.
</p>
</dd>
<dt><span><samp>video_stream_ptxt</samp></span></dt>
<dd><p>Print metadata on video stream. Includes <code>speed</code>, <code>tempo</code>, <code>order</code>, <code>pattern</code>,
<code>row</code> and <code>ts</code> (time in ms). Can be 1 (on) or 0 (off). Default is 1.
</p>
</dd>
</dl>
<a name="libopenmpt"></a>
<h3 class="section">3.14 libopenmpt<span class="pull-right"><a class="anchor hidden-xs" href="#libopenmpt" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libopenmpt" aria-hidden="true">TOC</a></span></h3>
<p>libopenmpt based module demuxer
</p>
<p>See <a href="https://lib.openmpt.org/libopenmpt/">https://lib.openmpt.org/libopenmpt/</a> for more information.
</p>
<p>Some files have multiple subsongs (tracks) this can be set with the <samp>subsong</samp>
option.
</p>
<p>It accepts the following options:
</p>
<dl compact="compact">
<dt><span><samp>subsong</samp></span></dt>
<dd><p>Set the subsong index. This can be either ’all’, ’auto’, or the index of the
subsong. Subsong indexes start at 0. The default is ’auto’.
</p>
<p>The default value is to let libopenmpt choose.
</p>
</dd>
<dt><span><samp>layout</samp></span></dt>
<dd><p>Set the channel layout. Valid values are 1, 2, and 4 channel layouts.
The default value is STEREO.
</p>
</dd>
<dt><span><samp>sample_rate</samp></span></dt>
<dd><p>Set the sample rate for libopenmpt to output.
Range is from 1000 to INT_MAX. The value default is 48000.
</p></dd>
</dl>
<a name="mov_002fmp4_002f3gp"></a>
<h3 class="section">3.15 mov/mp4/3gp<span class="pull-right"><a class="anchor hidden-xs" href="#mov_002fmp4_002f3gp" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-mov_002fmp4_002f3gp" aria-hidden="true">TOC</a></span></h3>
<p>Demuxer for Quicktime File Format & ISO/IEC Base Media File Format (ISO/IEC 14496-12 or MPEG-4 Part 12, ISO/IEC 15444-12 or JPEG 2000 Part 12).
</p>
<p>Registered extensions: mov, mp4, m4a, 3gp, 3g2, mj2, psp, m4b, ism, ismv, isma, f4v
</p>
<a name="Options-2"></a>
<h4 class="subsection">3.15.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-2" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-2" aria-hidden="true">TOC</a></span></h4>
<p>This demuxer accepts the following options:
</p><dl compact="compact">
<dt><span><samp>enable_drefs</samp></span></dt>
<dd><p>Enable loading of external tracks, disabled by default.
Enabling this can theoretically leak information in some use cases.
</p>
</dd>
<dt><span><samp>use_absolute_path</samp></span></dt>
<dd><p>Allows loading of external tracks via absolute paths, disabled by default.
Enabling this poses a security risk. It should only be enabled if the source
is known to be non-malicious.
</p>
</dd>
<dt><span><samp>seek_streams_individually</samp></span></dt>
<dd><p>When seeking, identify the closest point in each stream individually and demux packets in
that stream from identified point. This can lead to a different sequence of packets compared
to demuxing linearly from the beginning. Default is true.
</p>
</dd>
<dt><span><samp>ignore_editlist</samp></span></dt>
<dd><p>Ignore any edit list atoms. The demuxer, by default, modifies the stream index to reflect the
timeline described by the edit list. Default is false.
</p>
</dd>
<dt><span><samp>advanced_editlist</samp></span></dt>
<dd><p>Modify the stream index to reflect the timeline described by the edit list. <code>ignore_editlist</code>
must be set to false for this option to be effective.
If both <code>ignore_editlist</code> and this option are set to false, then only the
start of the stream index is modified to reflect initial dwell time or starting timestamp
described by the edit list. Default is true.
</p>
</dd>
<dt><span><samp>ignore_chapters</samp></span></dt>
<dd><p>Don’t parse chapters. This includes GoPro ’HiLight’ tags/moments. Note that chapters are
only parsed when input is seekable. Default is false.
</p>
</dd>
<dt><span><samp>use_mfra_for</samp></span></dt>
<dd><p>For seekable fragmented input, set fragment’s starting timestamp from media fragment random access box, if present.
</p>
<p>Following options are available:
</p><dl compact="compact">
<dt><span>‘<samp>auto</samp>’</span></dt>
<dd><p>Auto-detect whether to set mfra timestamps as PTS or DTS <em>(default)</em>
</p>
</dd>
<dt><span>‘<samp>dts</samp>’</span></dt>
<dd><p>Set mfra timestamps as DTS
</p>
</dd>
<dt><span>‘<samp>pts</samp>’</span></dt>
<dd><p>Set mfra timestamps as PTS
</p>
</dd>
<dt><span>‘<samp>0</samp>’</span></dt>
<dd><p>Don’t use mfra box to set timestamps
</p></dd>
</dl>
</dd>
<dt><span><samp>use_tfdt</samp></span></dt>
<dd><p>For fragmented input, set fragment’s starting timestamp to <code>baseMediaDecodeTime</code> from the <code>tfdt</code> box.
Default is enabled, which will prefer to use the <code>tfdt</code> box to set DTS. Disable to use the <code>earliest_presentation_time</code> from the <code>sidx</code> box.
In either case, the timestamp from the <code>mfra</code> box will be used if it’s available and <code>use_mfra_for</code> is
set to pts or dts.
</p>
</dd>
<dt><span><samp>export_all</samp></span></dt>
<dd><p>Export unrecognized boxes within the <var>udta</var> box as metadata entries. The first four
characters of the box type are set as the key. Default is false.
</p>
</dd>
<dt><span><samp>export_xmp</samp></span></dt>
<dd><p>Export entire contents of <var>XMP_</var> box and <var>uuid</var> box as a string with key <code>xmp</code>. Note that
if <code>export_all</code> is set and this option isn’t, the contents of <var>XMP_</var> box are still exported
but with key <code>XMP_</code>. Default is false.
</p>
</dd>
<dt><span><samp>activation_bytes</samp></span></dt>
<dd><p>4-byte key required to decrypt Audible AAX and AAX+ files. See Audible AAX subsection below.
</p>
</dd>
<dt><span><samp>audible_fixed_key</samp></span></dt>
<dd><p>Fixed key used for handling Audible AAX/AAX+ files. It has been pre-set so should not be necessary to
specify.
</p>
</dd>
<dt><span><samp>decryption_key</samp></span></dt>
<dd><p>16-byte key, in hex, to decrypt files encrypted using ISO Common Encryption (CENC/AES-128 CTR; ISO/IEC 23001-7).
</p>
</dd>
<dt><span><samp>max_stts_delta</samp></span></dt>
<dd><p>Very high sample deltas written in a trak’s stts box may occasionally be intended but usually they are written in
error or used to store a negative value for dts correction when treated as signed 32-bit integers. This option lets
the user set an upper limit, beyond which the delta is clamped to 1. Values greater than the limit if negative when
cast to int32 are used to adjust onward dts.
</p>
<p>Unit is the track time scale. Range is 0 to UINT_MAX. Default is <code>UINT_MAX - 48000*10</code> which allows upto
a 10 second dts correction for 48 kHz audio streams while accommodating 99.9% of <code>uint32</code> range.
</p></dd>
</dl>
<a name="Audible-AAX"></a>
<h4 class="subsection">3.15.2 Audible AAX<span class="pull-right"><a class="anchor hidden-xs" href="#Audible-AAX" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Audible-AAX" aria-hidden="true">TOC</a></span></h4>
<p>Audible AAX files are encrypted M4B files, and they can be decrypted by specifying a 4 byte activation secret.
</p><div class="example">
<pre class="example">ffmpeg -activation_bytes 1CEB00DA -i test.aax -vn -c:a copy output.mp4
</pre></div>
<a name="mpegts"></a>
<h3 class="section">3.16 mpegts<span class="pull-right"><a class="anchor hidden-xs" href="#mpegts" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-mpegts" aria-hidden="true">TOC</a></span></h3>
<p>MPEG-2 transport stream demuxer.
</p>
<p>This demuxer accepts the following options:
</p><dl compact="compact">
<dt><span><samp>resync_size</samp></span></dt>
<dd><p>Set size limit for looking up a new synchronization. Default value is
65536.
</p>
</dd>
<dt><span><samp>skip_unknown_pmt</samp></span></dt>
<dd><p>Skip PMTs for programs not defined in the PAT. Default value is 0.
</p>
</dd>
<dt><span><samp>fix_teletext_pts</samp></span></dt>
<dd><p>Override teletext packet PTS and DTS values with the timestamps calculated
from the PCR of the first program which the teletext stream is part of and is
not discarded. Default value is 1, set this option to 0 if you want your
teletext packet PTS and DTS values untouched.
</p>
</dd>
<dt><span><samp>ts_packetsize</samp></span></dt>
<dd><p>Output option carrying the raw packet size in bytes.
Show the detected raw packet size, cannot be set by the user.
</p>
</dd>
<dt><span><samp>scan_all_pmts</samp></span></dt>
<dd><p>Scan and combine all PMTs. The value is an integer with value from -1
to 1 (-1 means automatic setting, 1 means enabled, 0 means
disabled). Default value is -1.
</p>
</dd>
<dt><span><samp>merge_pmt_versions</samp></span></dt>
<dd><p>Re-use existing streams when a PMT’s version is updated and elementary
streams move to different PIDs. Default value is 0.
</p>
</dd>
<dt><span><samp>max_packet_size</samp></span></dt>
<dd><p>Set maximum size, in bytes, of packet emitted by the demuxer. Payloads above this size
are split across multiple packets. Range is 1 to INT_MAX/2. Default is 204800 bytes.
</p></dd>
</dl>
<a name="mpjpeg"></a>
<h3 class="section">3.17 mpjpeg<span class="pull-right"><a class="anchor hidden-xs" href="#mpjpeg" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-mpjpeg" aria-hidden="true">TOC</a></span></h3>
<p>MJPEG encapsulated in multi-part MIME demuxer.
</p>
<p>This demuxer allows reading of MJPEG, where each frame is represented as a part of
multipart/x-mixed-replace stream.
</p><dl compact="compact">
<dt><span><samp>strict_mime_boundary</samp></span></dt>
<dd><p>Default implementation applies a relaxed standard to multi-part MIME boundary detection,
to prevent regression with numerous existing endpoints not generating a proper MIME
MJPEG stream. Turning this option on by setting it to 1 will result in a stricter check
of the boundary value.
</p></dd>
</dl>
<a name="rawvideo"></a>
<h3 class="section">3.18 rawvideo<span class="pull-right"><a class="anchor hidden-xs" href="#rawvideo" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-rawvideo" aria-hidden="true">TOC</a></span></h3>
<p>Raw video demuxer.
</p>
<p>This demuxer allows one to read raw video data. Since there is no header
specifying the assumed video parameters, the user must specify them
in order to be able to decode the data correctly.
</p>
<p>This demuxer accepts the following options:
</p><dl compact="compact">
<dt><span><samp>framerate</samp></span></dt>
<dd><p>Set input video frame rate. Default value is 25.
</p>
</dd>
<dt><span><samp>pixel_format</samp></span></dt>
<dd><p>Set the input video pixel format. Default value is <code>yuv420p</code>.
</p>
</dd>
<dt><span><samp>video_size</samp></span></dt>
<dd><p>Set the input video size. This value must be specified explicitly.
</p></dd>
</dl>
<p>For example to read a rawvideo file <samp>input.raw</samp> with
<code>ffplay</code>, assuming a pixel format of <code>rgb24</code>, a video
size of <code>320x240</code>, and a frame rate of 10 images per second, use
the command:
</p><div class="example">
<pre class="example">ffplay -f rawvideo -pixel_format rgb24 -video_size 320x240 -framerate 10 input.raw
</pre></div>
<a name="sbg"></a>
<h3 class="section">3.19 sbg<span class="pull-right"><a class="anchor hidden-xs" href="#sbg" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-sbg" aria-hidden="true">TOC</a></span></h3>
<p>SBaGen script demuxer.
</p>
<p>This demuxer reads the script language used by SBaGen
<a href="http://uazu.net/sbagen/">http://uazu.net/sbagen/</a> to generate binaural beats sessions. A SBG
script looks like that:
</p><div class="example">
<pre class="example">-SE
a: 300-2.5/3 440+4.5/0
b: 300-2.5/0 440+4.5/3
off: -
NOW == a
+0:07:00 == b
+0:14:00 == a
+0:21:00 == b
+0:30:00 off
</pre></div>
<p>A SBG script can mix absolute and relative timestamps. If the script uses
either only absolute timestamps (including the script start time) or only
relative ones, then its layout is fixed, and the conversion is
straightforward. On the other hand, if the script mixes both kind of
timestamps, then the <var>NOW</var> reference for relative timestamps will be
taken from the current time of day at the time the script is read, and the
script layout will be frozen according to that reference. That means that if
the script is directly played, the actual times will match the absolute
timestamps up to the sound controller’s clock accuracy, but if the user
somehow pauses the playback or seeks, all times will be shifted accordingly.
</p>
<a name="tedcaptions"></a>
<h3 class="section">3.20 tedcaptions<span class="pull-right"><a class="anchor hidden-xs" href="#tedcaptions" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-tedcaptions" aria-hidden="true">TOC</a></span></h3>
<p>JSON captions used for <a href="http://www.ted.com/">TED Talks</a>.
</p>
<p>TED does not provide links to the captions, but they can be guessed from the
page. The file <samp>tools/bookmarklets.html</samp> from the FFmpeg source tree
contains a bookmarklet to expose them.
</p>
<p>This demuxer accepts the following option:
</p><dl compact="compact">
<dt><span><samp>start_time</samp></span></dt>
<dd><p>Set the start time of the TED talk, in milliseconds. The default is 15000
(15s). It is used to sync the captions with the downloadable videos, because
they include a 15s intro.
</p></dd>
</dl>
<p>Example: convert the captions to a format most players understand:
</p><div class="example">
<pre class="example">ffmpeg -i http://www.ted.com/talks/subtitles/id/1/lang/en talk1-en.srt
</pre></div>
<a name="vapoursynth"></a>
<h3 class="section">3.21 vapoursynth<span class="pull-right"><a class="anchor hidden-xs" href="#vapoursynth" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-vapoursynth" aria-hidden="true">TOC</a></span></h3>
<p>Vapoursynth wrapper.
</p>
<p>Due to security concerns, Vapoursynth scripts will not
be autodetected so the input format has to be forced. For ff* CLI tools,
add <code>-f vapoursynth</code> before the input <code>-i yourscript.vpy</code>.
</p>
<p>This demuxer accepts the following option:
</p><dl compact="compact">
<dt><span><samp>max_script_size</samp></span></dt>
<dd><p>The demuxer buffers the entire script into memory. Adjust this value to set the maximum buffer size,
which in turn, acts as a ceiling for the size of scripts that can be read.
Default is 1 MiB.
</p></dd>
</dl>
<a name="Muxers"></a>
<h2 class="chapter">4 Muxers<span class="pull-right"><a class="anchor hidden-xs" href="#Muxers" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Muxers" aria-hidden="true">TOC</a></span></h2>
<p>Muxers are configured elements in FFmpeg which allow writing
multimedia streams to a particular type of file.
</p>
<p>When you configure your FFmpeg build, all the supported muxers
are enabled by default. You can list all available muxers using the
configure option <code>--list-muxers</code>.
</p>
<p>You can disable all the muxers with the configure option
<code>--disable-muxers</code> and selectively enable / disable single muxers
with the options <code>--enable-muxer=<var>MUXER</var></code> /
<code>--disable-muxer=<var>MUXER</var></code>.
</p>
<p>The option <code>-muxers</code> of the ff* tools will display the list of
enabled muxers. Use <code>-formats</code> to view a combined list of
enabled demuxers and muxers.
</p>
<p>A description of some of the currently available muxers follows.
</p>
<span id="a64"></span><a name="a64-1"></a>
<h3 class="section">4.1 a64<span class="pull-right"><a class="anchor hidden-xs" href="#a64-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-a64-1" aria-hidden="true">TOC</a></span></h3>
<p>A64 muxer for Commodore 64 video. Accepts a single <code>a64_multi</code> or <code>a64_multi5</code> codec video stream.
</p>
<span id="adts"></span><a name="adts-1"></a>
<h3 class="section">4.2 adts<span class="pull-right"><a class="anchor hidden-xs" href="#adts-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-adts-1" aria-hidden="true">TOC</a></span></h3>
<p>Audio Data Transport Stream muxer. It accepts a single AAC stream.
</p>
<a name="Options-3"></a>
<h4 class="subsection">4.2.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-3" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-3" aria-hidden="true">TOC</a></span></h4>
<p>It accepts the following options:
</p>
<dl compact="compact">
<dt><span><samp>write_id3v2 <var>bool</var></samp></span></dt>
<dd><p>Enable to write ID3v2.4 tags at the start of the stream. Default is disabled.
</p>
</dd>
<dt><span><samp>write_apetag <var>bool</var></samp></span></dt>
<dd><p>Enable to write APE tags at the end of the stream. Default is disabled.
</p>
</dd>
<dt><span><samp>write_mpeg2 <var>bool</var></samp></span></dt>
<dd><p>Enable to set MPEG version bit in the ADTS frame header to 1 which indicates MPEG-2. Default is 0, which indicates MPEG-4.
</p>
</dd>
</dl>
<span id="aiff"></span><a name="aiff-1"></a>
<h3 class="section">4.3 aiff<span class="pull-right"><a class="anchor hidden-xs" href="#aiff-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-aiff-1" aria-hidden="true">TOC</a></span></h3>
<p>Audio Interchange File Format muxer.
</p>
<a name="Options-4"></a>
<h4 class="subsection">4.3.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-4" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-4" aria-hidden="true">TOC</a></span></h4>
<p>It accepts the following options:
</p>
<dl compact="compact">
<dt><span><samp>write_id3v2</samp></span></dt>
<dd><p>Enable ID3v2 tags writing when set to 1. Default is 0 (disabled).
</p>
</dd>
<dt><span><samp>id3v2_version</samp></span></dt>
<dd><p>Select ID3v2 version to write. Currently only version 3 and 4 (aka.
ID3v2.3 and ID3v2.4) are supported. The default is version 4.
</p>
</dd>
</dl>
<span id="alp"></span><a name="alp-1"></a>
<h3 class="section">4.4 alp<span class="pull-right"><a class="anchor hidden-xs" href="#alp-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-alp-1" aria-hidden="true">TOC</a></span></h3>
<p>Muxer for audio of High Voltage Software’s Lego Racers game. It accepts a single ADPCM_IMA_ALP stream
with no more than 2 channels nor a sample rate greater than 44100 Hz.
</p>
<p>Extensions: tun, pcm
</p>
<a name="Options-5"></a>
<h4 class="subsection">4.4.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-5" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-5" aria-hidden="true">TOC</a></span></h4>
<p>It accepts the following options:
</p>
<dl compact="compact">
<dt><span><samp>type <var>type</var></samp></span></dt>
<dd><p>Set file type.
</p>
<dl compact="compact">
<dt><span>‘<samp>tun</samp>’</span></dt>
<dd><p>Set file type as music. Must have a sample rate of 22050 Hz.
</p>
</dd>
<dt><span>‘<samp>pcm</samp>’</span></dt>
<dd><p>Set file type as sfx.
</p>
</dd>
<dt><span>‘<samp>auto</samp>’</span></dt>
<dd><p>Set file type as per output file extension. <code>.pcm</code> results in type <code>pcm</code> else type <code>tun</code> is set. <var>(default)</var>
</p>
</dd>
</dl>
</dd>
</dl>
<span id="asf"></span><a name="asf-2"></a>
<h3 class="section">4.5 asf<span class="pull-right"><a class="anchor hidden-xs" href="#asf-2" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-asf-2" aria-hidden="true">TOC</a></span></h3>
<p>Advanced Systems Format muxer.
</p>
<p>Note that Windows Media Audio (wma) and Windows Media Video (wmv) use this
muxer too.
</p>
<a name="Options-6"></a>
<h4 class="subsection">4.5.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-6" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-6" aria-hidden="true">TOC</a></span></h4>
<p>It accepts the following options:
</p>
<dl compact="compact">
<dt><span><samp>packet_size</samp></span></dt>
<dd><p>Set the muxer packet size. By tuning this setting you may reduce data
fragmentation or muxer overhead depending on your source. Default value is
3200, minimum is 100, maximum is 64k.
</p>
</dd>
</dl>
<span id="avi"></span><a name="avi-1"></a>
<h3 class="section">4.6 avi<span class="pull-right"><a class="anchor hidden-xs" href="#avi-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-avi-1" aria-hidden="true">TOC</a></span></h3>
<p>Audio Video Interleaved muxer.
</p>
<a name="Options-7"></a>
<h4 class="subsection">4.6.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-7" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-7" aria-hidden="true">TOC</a></span></h4>
<p>It accepts the following options:
</p>
<dl compact="compact">
<dt><span><samp>reserve_index_space</samp></span></dt>
<dd><p>Reserve the specified amount of bytes for the OpenDML master index of each
stream within the file header. By default additional master indexes are
embedded within the data packets if there is no space left in the first master
index and are linked together as a chain of indexes. This index structure can
cause problems for some use cases, e.g. third-party software strictly relying
on the OpenDML index specification or when file seeking is slow. Reserving
enough index space in the file header avoids these problems.
</p>
<p>The required index space depends on the output file size and should be about 16
bytes per gigabyte. When this option is omitted or set to zero the necessary
index space is guessed.
</p>
</dd>
<dt><span><samp>write_channel_mask</samp></span></dt>
<dd><p>Write the channel layout mask into the audio stream header.
</p>
<p>This option is enabled by default. Disabling the channel mask can be useful in
specific scenarios, e.g. when merging multiple audio streams into one for
compatibility with software that only supports a single audio stream in AVI
(see <a data-manual="ffmpeg-filters" href="ffmpeg-filters.html#amerge">(ffmpeg-filters)the "amerge" section in the ffmpeg-filters manual</a>).
</p>
</dd>
<dt><span><samp>flipped_raw_rgb</samp></span></dt>
<dd><p>If set to true, store positive height for raw RGB bitmaps, which indicates
bitmap is stored bottom-up. Note that this option does not flip the bitmap
which has to be done manually beforehand, e.g. by using the vflip filter.
Default is <var>false</var> and indicates bitmap is stored top down.
</p>
</dd>
</dl>
<span id="chromaprint"></span><a name="chromaprint-1"></a>
<h3 class="section">4.7 chromaprint<span class="pull-right"><a class="anchor hidden-xs" href="#chromaprint-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-chromaprint-1" aria-hidden="true">TOC</a></span></h3>
<p>Chromaprint fingerprinter.
</p>
<p>This muxer feeds audio data to the Chromaprint library,
which generates a fingerprint for the provided audio data. See <a href="https://acoustid.org/chromaprint">https://acoustid.org/chromaprint</a>
</p>
<p>It takes a single signed native-endian 16-bit raw audio stream of at most 2 channels.
</p>
<a name="Options-8"></a>
<h4 class="subsection">4.7.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-8" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-8" aria-hidden="true">TOC</a></span></h4>
<dl compact="compact">
<dt><span><samp>silence_threshold</samp></span></dt>
<dd><p>Threshold for detecting silence. Range is from -1 to 32767, where -1 disables
silence detection. Silence detection can only be used with version 3 of the
algorithm.
Silence detection must be disabled for use with the AcoustID service. Default is -1.
</p>
</dd>
<dt><span><samp>algorithm</samp></span></dt>
<dd><p>Version of algorithm to fingerprint with. Range is 0 to 4.
Version 3 enables silence detection. Default is 1.
</p>
</dd>
<dt><span><samp>fp_format</samp></span></dt>
<dd><p>Format to output the fingerprint as. Accepts the following options:
</p><dl compact="compact">
<dt><span>‘<samp>raw</samp>’</span></dt>
<dd><p>Binary raw fingerprint
</p>
</dd>
<dt><span>‘<samp>compressed</samp>’</span></dt>
<dd><p>Binary compressed fingerprint
</p>
</dd>
<dt><span>‘<samp>base64</samp>’</span></dt>
<dd><p>Base64 compressed fingerprint <em>(default)</em>
</p>
</dd>
</dl>
</dd>
</dl>
<span id="crc"></span><a name="crc-1"></a>
<h3 class="section">4.8 crc<span class="pull-right"><a class="anchor hidden-xs" href="#crc-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-crc-1" aria-hidden="true">TOC</a></span></h3>
<p>CRC (Cyclic Redundancy Check) testing format.
</p>
<p>This muxer computes and prints the Adler-32 CRC of all the input audio
and video frames. By default audio frames are converted to signed
16-bit raw audio and video frames to raw video before computing the
CRC.
</p>
<p>The output of the muxer consists of a single line of the form:
CRC=0x<var>CRC</var>, where <var>CRC</var> is a hexadecimal number 0-padded to
8 digits containing the CRC for all the decoded input frames.
</p>
<p>See also the <a href="#framecrc">framecrc</a> muxer.
</p>
<a name="Examples-2"></a>
<h4 class="subsection">4.8.1 Examples<span class="pull-right"><a class="anchor hidden-xs" href="#Examples-2" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Examples-2" aria-hidden="true">TOC</a></span></h4>
<p>For example to compute the CRC of the input, and store it in the file
<samp>out.crc</samp>:
</p><div class="example">
<pre class="example">ffmpeg -i INPUT -f crc out.crc
</pre></div>
<p>You can print the CRC to stdout with the command:
</p><div class="example">
<pre class="example">ffmpeg -i INPUT -f crc -
</pre></div>
<p>You can select the output format of each frame with <code>ffmpeg</code> by
specifying the audio and video codec and format. For example to
compute the CRC of the input audio converted to PCM unsigned 8-bit
and the input video converted to MPEG-2 video, use the command:
</p><div class="example">
<pre class="example">ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f crc -
</pre></div>
<span id="dash"></span><a name="dash-2"></a>
<h3 class="section">4.9 dash<span class="pull-right"><a class="anchor hidden-xs" href="#dash-2" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-dash-2" aria-hidden="true">TOC</a></span></h3>
<p>Dynamic Adaptive Streaming over HTTP (DASH) muxer that creates segments
and manifest files according to the MPEG-DASH standard ISO/IEC 23009-1:2014.
</p>
<p>For more information see:
</p>
<ul>
<li> ISO DASH Specification: <a href="http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip">http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip</a>
</li><li> WebM DASH Specification: <a href="https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification">https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification</a>
</li></ul>
<p>It creates a MPD manifest file and segment files for each stream.
</p>
<p>The segment filename might contain pre-defined identifiers used with SegmentTemplate
as defined in section 5.3.9.4.4 of the standard. Available identifiers are "$RepresentationID$",
"$Number$", "$Bandwidth$" and "$Time$".
In addition to the standard identifiers, an ffmpeg-specific "$ext$" identifier is also supported.
When specified ffmpeg will replace $ext$ in the file name with muxing format’s extensions such as mp4, webm etc.,
</p>
<div class="example">
<pre class="example">ffmpeg -re -i <input> -map 0 -map 0 -c:a libfdk_aac -c:v libx264 \
-b:v:0 800k -b:v:1 300k -s:v:1 320x170 -profile:v:1 baseline \
-profile:v:0 main -bf 1 -keyint_min 120 -g 120 -sc_threshold 0 \
-b_strategy 0 -ar:a:1 22050 -use_timeline 1 -use_template 1 \
-window_size 5 -adaptation_sets "id=0,streams=v id=1,streams=a" \
-f dash /path/to/out.mpd
</pre></div>
<dl compact="compact">
<dt><span><samp>seg_duration <var>duration</var></samp></span></dt>
<dd><p>Set the segment length in seconds (fractional value can be set). The value is
treated as average segment duration when <var>use_template</var> is enabled and
<var>use_timeline</var> is disabled and as minimum segment duration for all the other
use cases.
</p></dd>
<dt><span><samp>frag_duration <var>duration</var></samp></span></dt>
<dd><p>Set the length in seconds of fragments within segments (fractional value can be set).
</p></dd>
<dt><span><samp>frag_type <var>type</var></samp></span></dt>
<dd><p>Set the type of interval for fragmentation.
</p></dd>
<dt><span><samp>window_size <var>size</var></samp></span></dt>
<dd><p>Set the maximum number of segments kept in the manifest.
</p></dd>
<dt><span><samp>extra_window_size <var>size</var></samp></span></dt>
<dd><p>Set the maximum number of segments kept outside of the manifest before removing from disk.
</p></dd>
<dt><span><samp>remove_at_exit <var>remove</var></samp></span></dt>
<dd><p>Enable (1) or disable (0) removal of all segments when finished.
</p></dd>
<dt><span><samp>use_template <var>template</var></samp></span></dt>
<dd><p>Enable (1) or disable (0) use of SegmentTemplate instead of SegmentList.
</p></dd>
<dt><span><samp>use_timeline <var>timeline</var></samp></span></dt>
<dd><p>Enable (1) or disable (0) use of SegmentTimeline in SegmentTemplate.
</p></dd>
<dt><span><samp>single_file <var>single_file</var></samp></span></dt>
<dd><p>Enable (1) or disable (0) storing all segments in one file, accessed using byte ranges.
</p></dd>
<dt><span><samp>single_file_name <var>file_name</var></samp></span></dt>
<dd><p>DASH-templated name to be used for baseURL. Implies <var>single_file</var> set to "1". In the template, "$ext$" is replaced with the file name extension specific for the segment format.
</p></dd>
<dt><span><samp>init_seg_name <var>init_name</var></samp></span></dt>
<dd><p>DASH-templated name to used for the initialization segment. Default is "init-stream$RepresentationID$.$ext$". "$ext$" is replaced with the file name extension specific for the segment format.
</p></dd>
<dt><span><samp>media_seg_name <var>segment_name</var></samp></span></dt>
<dd><p>DASH-templated name to used for the media segments. Default is "chunk-stream$RepresentationID$-$Number%05d$.$ext$". "$ext$" is replaced with the file name extension specific for the segment format.
</p></dd>
<dt><span><samp>utc_timing_url <var>utc_url</var></samp></span></dt>
<dd><p>URL of the page that will return the UTC timestamp in ISO format. Example: "https://time.akamai.com/?iso"
</p></dd>
<dt><span><samp>method <var>method</var></samp></span></dt>
<dd><p>Use the given HTTP method to create output files. Generally set to PUT or POST.
</p></dd>
<dt><span><samp>http_user_agent <var>user_agent</var></samp></span></dt>
<dd><p>Override User-Agent field in HTTP header. Applicable only for HTTP output.
</p></dd>
<dt><span><samp>http_persistent <var>http_persistent</var></samp></span></dt>
<dd><p>Use persistent HTTP connections. Applicable only for HTTP output.
</p></dd>
<dt><span><samp>hls_playlist <var>hls_playlist</var></samp></span></dt>
<dd><p>Generate HLS playlist files as well. The master playlist is generated with the filename <var>hls_master_name</var>.
One media playlist file is generated for each stream with filenames media_0.m3u8, media_1.m3u8, etc.
</p></dd>
<dt><span><samp>hls_master_name <var>file_name</var></samp></span></dt>
<dd><p>HLS master playlist name. Default is "master.m3u8".
</p></dd>
<dt><span><samp>streaming <var>streaming</var></samp></span></dt>
<dd><p>Enable (1) or disable (0) chunk streaming mode of output. In chunk streaming
mode, each frame will be a moof fragment which forms a chunk.
</p></dd>
<dt><span><samp>adaptation_sets <var>adaptation_sets</var></samp></span></dt>
<dd><p>Assign streams to AdaptationSets. Syntax is "id=x,streams=a,b,c id=y,streams=d,e" with x and y being the IDs
of the adaptation sets and a,b,c,d and e are the indices of the mapped streams.
</p>
<p>To map all video (or audio) streams to an AdaptationSet, "v" (or "a") can be used as stream identifier instead of IDs.
</p>
<p>When no assignment is defined, this defaults to an AdaptationSet for each stream.
</p>
<p>Optional syntax is "id=x,seg_duration=x,frag_duration=x,frag_type=type,descriptor=descriptor_string,streams=a,b,c id=y,seg_duration=y,frag_type=type,streams=d,e" and so on,
descriptor is useful to the scheme defined by ISO/IEC 23009-1:2014/Amd.2:2015.
For example, -adaptation_sets "id=0,descriptor=<SupplementalProperty schemeIdUri=\"urn:mpeg:dash:srd:2014\" value=\"0,0,0,1,1,2,2\"/>,streams=v".
Please note that descriptor string should be a self-closing xml tag.
seg_duration, frag_duration and frag_type override the global option values for each adaptation set.
For example, -adaptation_sets "id=0,seg_duration=2,frag_duration=1,frag_type=duration,streams=v id=1,seg_duration=2,frag_type=none,streams=a"
type_id marks an adaptation set as containing streams meant to be used for Trick Mode for the referenced adaptation set.
For example, -adaptation_sets "id=0,seg_duration=2,frag_type=none,streams=0 id=1,seg_duration=10,frag_type=none,trick_id=0,streams=1"
</p></dd>
<dt><span><samp>timeout <var>timeout</var></samp></span></dt>
<dd><p>Set timeout for socket I/O operations. Applicable only for HTTP output.
</p></dd>
<dt><span><samp>index_correction <var>index_correction</var></samp></span></dt>
<dd><p>Enable (1) or Disable (0) segment index correction logic. Applicable only when
<var>use_template</var> is enabled and <var>use_timeline</var> is disabled.
</p>
<p>When enabled, the logic monitors the flow of segment indexes. If a streams’s
segment index value is not at the expected real time position, then the logic
corrects that index value.
</p>
<p>Typically this logic is needed in live streaming use cases. The network bandwidth
fluctuations are common during long run streaming. Each fluctuation can cause
the segment indexes fall behind the expected real time position.
</p></dd>
<dt><span><samp>format_options <var>options_list</var></samp></span></dt>
<dd><p>Set container format (mp4/webm) options using a <code>:</code> separated list of
key=value parameters. Values containing <code>:</code> special characters must be
escaped.
</p>
</dd>
<dt><span><samp>global_sidx <var>global_sidx</var></samp></span></dt>
<dd><p>Write global SIDX atom. Applicable only for single file, mp4 output, non-streaming mode.
</p>
</dd>
<dt><span><samp>dash_segment_type <var>dash_segment_type</var></samp></span></dt>
<dd><p>Possible values:
</p><dl compact="compact">
<dt><span><samp>auto</samp></span></dt>
<dd><p>If this flag is set, the dash segment files format will be selected based on the stream codec. This is the default mode.
</p>
</dd>
<dt><span><samp>mp4</samp></span></dt>
<dd><p>If this flag is set, the dash segment files will be in in ISOBMFF format.
</p>
</dd>
<dt><span><samp>webm</samp></span></dt>
<dd><p>If this flag is set, the dash segment files will be in in WebM format.
</p></dd>
</dl>
</dd>
<dt><span><samp>ignore_io_errors <var>ignore_io_errors</var></samp></span></dt>
<dd><p>Ignore IO errors during open and write. Useful for long-duration runs with network output.
</p>
</dd>
<dt><span><samp>lhls <var>lhls</var></samp></span></dt>
<dd><p>Enable Low-latency HLS(LHLS). Adds #EXT-X-PREFETCH tag with current segment’s URI.
hls.js player folks are trying to standardize an open LHLS spec. The draft spec is available in https://github.com/video-dev/hlsjs-rfcs/blob/lhls-spec/proposals/0001-lhls.md
This option tries to comply with the above open spec.
It enables <var>streaming</var> and <var>hls_playlist</var> options automatically.
This is an experimental feature.
</p>
<p>Note: This is not Apple’s version LHLS. See <a href="https://datatracker.ietf.org/doc/html/draft-pantos-hls-rfc8216bis">https://datatracker.ietf.org/doc/html/draft-pantos-hls-rfc8216bis</a>
</p>
</dd>
<dt><span><samp>ldash <var>ldash</var></samp></span></dt>
<dd><p>Enable Low-latency Dash by constraining the presence and values of some elements.
</p>
</dd>
<dt><span><samp>master_m3u8_publish_rate <var>master_m3u8_publish_rate</var></samp></span></dt>
<dd><p>Publish master playlist repeatedly every after specified number of segment intervals.
</p>
</dd>
<dt><span><samp>write_prft <var>write_prft</var></samp></span></dt>
<dd><p>Write Producer Reference Time elements on supported streams. This also enables writing
prft boxes in the underlying muxer. Applicable only when the <var>utc_url</var> option is enabled.
It’s set to auto by default, in which case the muxer will attempt to enable it only in modes
that require it.
</p>
</dd>
<dt><span><samp>mpd_profile <var>mpd_profile</var></samp></span></dt>
<dd><p>Set one or more manifest profiles.
</p>
</dd>
<dt><span><samp>http_opts <var>http_opts</var></samp></span></dt>
<dd><p>A :-separated list of key=value options to pass to the underlying HTTP
protocol. Applicable only for HTTP output.
</p>
</dd>
<dt><span><samp>target_latency <var>target_latency</var></samp></span></dt>
<dd><p>Set an intended target latency in seconds (fractional value can be set) for serving. Applicable only when <var>streaming</var> and <var>write_prft</var> options are enabled.
This is an informative fields clients can use to measure the latency of the service.
</p>
</dd>
<dt><span><samp>min_playback_rate <var>min_playback_rate</var></samp></span></dt>
<dd><p>Set the minimum playback rate indicated as appropriate for the purposes of automatically
adjusting playback latency and buffer occupancy during normal playback by clients.
</p>
</dd>
<dt><span><samp>max_playback_rate <var>max_playback_rate</var></samp></span></dt>
<dd><p>Set the maximum playback rate indicated as appropriate for the purposes of automatically
adjusting playback latency and buffer occupancy during normal playback by clients.
</p>
</dd>
<dt><span><samp>update_period <var>update_period</var></samp></span></dt>
<dd><p>Set the mpd update period ,for dynamic content.
The unit is second.
</p>
</dd>
</dl>
<span id="fifo"></span><a name="fifo-1"></a>
<h3 class="section">4.10 fifo<span class="pull-right"><a class="anchor hidden-xs" href="#fifo-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-fifo-1" aria-hidden="true">TOC</a></span></h3>
<p>The fifo pseudo-muxer allows the separation of encoding and muxing by using
first-in-first-out queue and running the actual muxer in a separate thread. This
is especially useful in combination with the <a href="#tee">tee</a> muxer and can be used to
send data to several destinations with different reliability/writing speed/latency.
</p>
<p>API users should be aware that callback functions (interrupt_callback,
io_open and io_close) used within its AVFormatContext must be thread-safe.
</p>
<p>The behavior of the fifo muxer if the queue fills up or if the output fails is
selectable,
</p>
<ul>
<li> output can be transparently restarted with configurable delay between retries
based on real time or time of the processed stream.
</li><li> encoding can be blocked during temporary failure, or continue transparently
dropping packets in case fifo queue fills up.
</li></ul>
<dl compact="compact">
<dt><span><samp>fifo_format</samp></span></dt>
<dd><p>Specify the format name. Useful if it cannot be guessed from the
output name suffix.
</p>
</dd>
<dt><span><samp>queue_size</samp></span></dt>
<dd><p>Specify size of the queue (number of packets). Default value is 60.
</p>
</dd>
<dt><span><samp>format_opts</samp></span></dt>
<dd><p>Specify format options for the underlying muxer. Muxer options can be specified
as a list of <var>key</var>=<var>value</var> pairs separated by ’:’.
</p>
</dd>
<dt><span><samp>drop_pkts_on_overflow <var>bool</var></samp></span></dt>
<dd><p>If set to 1 (true), in case the fifo queue fills up, packets will be dropped
rather than blocking the encoder. This makes it possible to continue streaming without
delaying the input, at the cost of omitting part of the stream. By default
this option is set to 0 (false), so in such cases the encoder will be blocked
until the muxer processes some of the packets and none of them is lost.
</p>
</dd>
<dt><span><samp>attempt_recovery <var>bool</var></samp></span></dt>
<dd><p>If failure occurs, attempt to recover the output. This is especially useful
when used with network output, since it makes it possible to restart streaming transparently.
By default this option is set to 0 (false).
</p>
</dd>
<dt><span><samp>max_recovery_attempts</samp></span></dt>
<dd><p>Sets maximum number of successive unsuccessful recovery attempts after which
the output fails permanently. By default this option is set to 0 (unlimited).
</p>
</dd>
<dt><span><samp>recovery_wait_time <var>duration</var></samp></span></dt>
<dd><p>Waiting time before the next recovery attempt after previous unsuccessful
recovery attempt. Default value is 5 seconds.
</p>
</dd>
<dt><span><samp>recovery_wait_streamtime <var>bool</var></samp></span></dt>
<dd><p>If set to 0 (false), the real time is used when waiting for the recovery
attempt (i.e. the recovery will be attempted after at least
recovery_wait_time seconds).
If set to 1 (true), the time of the processed stream is taken into account
instead (i.e. the recovery will be attempted after at least <var>recovery_wait_time</var>
seconds of the stream is omitted).
By default, this option is set to 0 (false).
</p>
</dd>
<dt><span><samp>recover_any_error <var>bool</var></samp></span></dt>
<dd><p>If set to 1 (true), recovery will be attempted regardless of type of the error
causing the failure. By default this option is set to 0 (false) and in case of
certain (usually permanent) errors the recovery is not attempted even when
<var>attempt_recovery</var> is set to 1.
</p>
</dd>
<dt><span><samp>restart_with_keyframe <var>bool</var></samp></span></dt>
<dd><p>Specify whether to wait for the keyframe after recovering from
queue overflow or failure. This option is set to 0 (false) by default.
</p>
</dd>
<dt><span><samp>timeshift <var>duration</var></samp></span></dt>
<dd><p>Buffer the specified amount of packets and delay writing the output. Note that
<var>queue_size</var> must be big enough to store the packets for timeshift. At the
end of the input the fifo buffer is flushed at realtime speed.
</p>
</dd>
</dl>
<a name="Examples-3"></a>
<h4 class="subsection">4.10.1 Examples<span class="pull-right"><a class="anchor hidden-xs" href="#Examples-3" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Examples-3" aria-hidden="true">TOC</a></span></h4>
<ul>
<li> Stream something to rtmp server, continue processing the stream at real-time
rate even in case of temporary failure (network outage) and attempt to recover
streaming every second indefinitely.
<div class="example">
<pre class="example">ffmpeg -re -i ... -c:v libx264 -c:a aac -f fifo -fifo_format flv -map 0:v -map 0:a
-drop_pkts_on_overflow 1 -attempt_recovery 1 -recovery_wait_time 1 rtmp://example.com/live/stream_name
</pre></div>
</li></ul>
<a name="flv"></a>
<h3 class="section">4.11 flv<span class="pull-right"><a class="anchor hidden-xs" href="#flv" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-flv" aria-hidden="true">TOC</a></span></h3>
<p>Adobe Flash Video Format muxer.
</p>
<p>This muxer accepts the following options:
</p>
<dl compact="compact">
<dt><span><samp>flvflags <var>flags</var></samp></span></dt>
<dd><p>Possible values:
</p>
<dl compact="compact">
<dt><span>‘<samp>aac_seq_header_detect</samp>’</span></dt>
<dd><p>Place AAC sequence header based on audio stream data.
</p>
</dd>
<dt><span>‘<samp>no_sequence_end</samp>’</span></dt>
<dd><p>Disable sequence end tag.
</p>
</dd>
<dt><span>‘<samp>no_metadata</samp>’</span></dt>
<dd><p>Disable metadata tag.
</p>
</dd>
<dt><span>‘<samp>no_duration_filesize</samp>’</span></dt>
<dd><p>Disable duration and filesize in metadata when they are equal to zero
at the end of stream. (Be used to non-seekable living stream).
</p>
</dd>
<dt><span>‘<samp>add_keyframe_index</samp>’</span></dt>
<dd><p>Used to facilitate seeking; particularly for HTTP pseudo streaming.
</p></dd>
</dl>
</dd>
</dl>
<span id="framecrc"></span><a name="framecrc-1"></a>
<h3 class="section">4.12 framecrc<span class="pull-right"><a class="anchor hidden-xs" href="#framecrc-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-framecrc-1" aria-hidden="true">TOC</a></span></h3>
<p>Per-packet CRC (Cyclic Redundancy Check) testing format.
</p>
<p>This muxer computes and prints the Adler-32 CRC for each audio
and video packet. By default audio frames are converted to signed
16-bit raw audio and video frames to raw video before computing the
CRC.
</p>
<p>The output of the muxer consists of a line for each audio and video
packet of the form:
</p><div class="example">
<pre class="example"><var>stream_index</var>, <var>packet_dts</var>, <var>packet_pts</var>, <var>packet_duration</var>, <var>packet_size</var>, 0x<var>CRC</var>
</pre></div>
<p><var>CRC</var> is a hexadecimal number 0-padded to 8 digits containing the
CRC of the packet.
</p>
<a name="Examples-4"></a>
<h4 class="subsection">4.12.1 Examples<span class="pull-right"><a class="anchor hidden-xs" href="#Examples-4" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Examples-4" aria-hidden="true">TOC</a></span></h4>
<p>For example to compute the CRC of the audio and video frames in
<samp>INPUT</samp>, converted to raw audio and video packets, and store it
in the file <samp>out.crc</samp>:
</p><div class="example">
<pre class="example">ffmpeg -i INPUT -f framecrc out.crc
</pre></div>
<p>To print the information to stdout, use the command:
</p><div class="example">
<pre class="example">ffmpeg -i INPUT -f framecrc -
</pre></div>
<p>With <code>ffmpeg</code>, you can select the output format to which the
audio and video frames are encoded before computing the CRC for each
packet by specifying the audio and video codec. For example, to
compute the CRC of each decoded input audio frame converted to PCM
unsigned 8-bit and of each decoded input video frame converted to
MPEG-2 video, use the command:
</p><div class="example">
<pre class="example">ffmpeg -i INPUT -c:a pcm_u8 -c:v mpeg2video -f framecrc -
</pre></div>
<p>See also the <a href="#crc">crc</a> muxer.
</p>
<span id="framehash"></span><a name="framehash-1"></a>
<h3 class="section">4.13 framehash<span class="pull-right"><a class="anchor hidden-xs" href="#framehash-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-framehash-1" aria-hidden="true">TOC</a></span></h3>
<p>Per-packet hash testing format.
</p>
<p>This muxer computes and prints a cryptographic hash for each audio
and video packet. This can be used for packet-by-packet equality
checks without having to individually do a binary comparison on each.
</p>
<p>By default audio frames are converted to signed 16-bit raw audio and
video frames to raw video before computing the hash, but the output
of explicit conversions to other codecs can also be used. It uses the
SHA-256 cryptographic hash function by default, but supports several
other algorithms.
</p>
<p>The output of the muxer consists of a line for each audio and video
packet of the form:
</p><div class="example">
<pre class="example"><var>stream_index</var>, <var>packet_dts</var>, <var>packet_pts</var>, <var>packet_duration</var>, <var>packet_size</var>, <var>hash</var>
</pre></div>
<p><var>hash</var> is a hexadecimal number representing the computed hash
for the packet.
</p>
<dl compact="compact">
<dt><span><samp>hash <var>algorithm</var></samp></span></dt>
<dd><p>Use the cryptographic hash function specified by the string <var>algorithm</var>.
Supported values include <code>MD5</code>, <code>murmur3</code>, <code>RIPEMD128</code>,
<code>RIPEMD160</code>, <code>RIPEMD256</code>, <code>RIPEMD320</code>, <code>SHA160</code>,
<code>SHA224</code>, <code>SHA256</code> (default), <code>SHA512/224</code>, <code>SHA512/256</code>,
<code>SHA384</code>, <code>SHA512</code>, <code>CRC32</code> and <code>adler32</code>.
</p>
</dd>
</dl>
<a name="Examples-5"></a>
<h4 class="subsection">4.13.1 Examples<span class="pull-right"><a class="anchor hidden-xs" href="#Examples-5" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Examples-5" aria-hidden="true">TOC</a></span></h4>
<p>To compute the SHA-256 hash of the audio and video frames in <samp>INPUT</samp>,
converted to raw audio and video packets, and store it in the file
<samp>out.sha256</samp>:
</p><div class="example">
<pre class="example">ffmpeg -i INPUT -f framehash out.sha256
</pre></div>
<p>To print the information to stdout, using the MD5 hash function, use
the command:
</p><div class="example">
<pre class="example">ffmpeg -i INPUT -f framehash -hash md5 -
</pre></div>
<p>See also the <a href="#hash">hash</a> muxer.
</p>
<span id="framemd5"></span><a name="framemd5-1"></a>
<h3 class="section">4.14 framemd5<span class="pull-right"><a class="anchor hidden-xs" href="#framemd5-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-framemd5-1" aria-hidden="true">TOC</a></span></h3>
<p>Per-packet MD5 testing format.
</p>
<p>This is a variant of the <a href="#framehash">framehash</a> muxer. Unlike that muxer,
it defaults to using the MD5 hash function.
</p>
<a name="Examples-6"></a>
<h4 class="subsection">4.14.1 Examples<span class="pull-right"><a class="anchor hidden-xs" href="#Examples-6" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Examples-6" aria-hidden="true">TOC</a></span></h4>
<p>To compute the MD5 hash of the audio and video frames in <samp>INPUT</samp>,
converted to raw audio and video packets, and store it in the file
<samp>out.md5</samp>:
</p><div class="example">
<pre class="example">ffmpeg -i INPUT -f framemd5 out.md5
</pre></div>
<p>To print the information to stdout, use the command:
</p><div class="example">
<pre class="example">ffmpeg -i INPUT -f framemd5 -
</pre></div>
<p>See also the <a href="#framehash">framehash</a> and <a href="#md5">md5</a> muxers.
</p>
<span id="gif"></span><a name="gif-2"></a>
<h3 class="section">4.15 gif<span class="pull-right"><a class="anchor hidden-xs" href="#gif-2" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-gif-2" aria-hidden="true">TOC</a></span></h3>
<p>Animated GIF muxer.
</p>
<p>It accepts the following options:
</p>
<dl compact="compact">
<dt><span><samp>loop</samp></span></dt>
<dd><p>Set the number of times to loop the output. Use <code>-1</code> for no loop, <code>0</code>
for looping indefinitely (default).
</p>
</dd>
<dt><span><samp>final_delay</samp></span></dt>
<dd><p>Force the delay (expressed in centiseconds) after the last frame. Each frame
ends with a delay until the next frame. The default is <code>-1</code>, which is a
special value to tell the muxer to re-use the previous delay. In case of a
loop, you might want to customize this value to mark a pause for instance.
</p></dd>
</dl>
<p>For example, to encode a gif looping 10 times, with a 5 seconds delay between
the loops:
</p><div class="example">
<pre class="example">ffmpeg -i INPUT -loop 10 -final_delay 500 out.gif
</pre></div>
<p>Note 1: if you wish to extract the frames into separate GIF files, you need to
force the <a href="#image2">image2</a> muxer:
</p><div class="example">
<pre class="example">ffmpeg -i INPUT -c:v gif -f image2 "out%d.gif"
</pre></div>
<p>Note 2: the GIF format has a very large time base: the delay between two frames
can therefore not be smaller than one centi second.
</p>
<span id="hash"></span><a name="hash-1"></a>
<h3 class="section">4.16 hash<span class="pull-right"><a class="anchor hidden-xs" href="#hash-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-hash-1" aria-hidden="true">TOC</a></span></h3>
<p>Hash testing format.
</p>
<p>This muxer computes and prints a cryptographic hash of all the input
audio and video frames. This can be used for equality checks without
having to do a complete binary comparison.
</p>
<p>By default audio frames are converted to signed 16-bit raw audio and
video frames to raw video before computing the hash, but the output
of explicit conversions to other codecs can also be used. Timestamps
are ignored. It uses the SHA-256 cryptographic hash function by default,
but supports several other algorithms.
</p>
<p>The output of the muxer consists of a single line of the form:
<var>algo</var>=<var>hash</var>, where <var>algo</var> is a short string representing
the hash function used, and <var>hash</var> is a hexadecimal number
representing the computed hash.
</p>
<dl compact="compact">
<dt><span><samp>hash <var>algorithm</var></samp></span></dt>
<dd><p>Use the cryptographic hash function specified by the string <var>algorithm</var>.
Supported values include <code>MD5</code>, <code>murmur3</code>, <code>RIPEMD128</code>,
<code>RIPEMD160</code>, <code>RIPEMD256</code>, <code>RIPEMD320</code>, <code>SHA160</code>,
<code>SHA224</code>, <code>SHA256</code> (default), <code>SHA512/224</code>, <code>SHA512/256</code>,
<code>SHA384</code>, <code>SHA512</code>, <code>CRC32</code> and <code>adler32</code>.
</p>
</dd>
</dl>
<a name="Examples-7"></a>
<h4 class="subsection">4.16.1 Examples<span class="pull-right"><a class="anchor hidden-xs" href="#Examples-7" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Examples-7" aria-hidden="true">TOC</a></span></h4>
<p>To compute the SHA-256 hash of the input converted to raw audio and
video, and store it in the file <samp>out.sha256</samp>:
</p><div class="example">
<pre class="example">ffmpeg -i INPUT -f hash out.sha256
</pre></div>
<p>To print an MD5 hash to stdout use the command:
</p><div class="example">
<pre class="example">ffmpeg -i INPUT -f hash -hash md5 -
</pre></div>
<p>See also the <a href="#framehash">framehash</a> muxer.
</p>
<span id="hls"></span><a name="hls-2"></a>
<h3 class="section">4.17 hls<span class="pull-right"><a class="anchor hidden-xs" href="#hls-2" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-hls-2" aria-hidden="true">TOC</a></span></h3>
<p>Apple HTTP Live Streaming muxer that segments MPEG-TS according to
the HTTP Live Streaming (HLS) specification.
</p>
<p>It creates a playlist file, and one or more segment files. The output filename
specifies the playlist filename.
</p>
<p>By default, the muxer creates a file for each segment produced. These files
have the same name as the playlist, followed by a sequential number and a
.ts extension.
</p>
<p>Make sure to require a closed GOP when encoding and to set the GOP
size to fit your segment time constraint.
</p>
<p>For example, to convert an input file with <code>ffmpeg</code>:
</p><div class="example">
<pre class="example">ffmpeg -i in.mkv -c:v h264 -flags +cgop -g 30 -hls_time 1 out.m3u8
</pre></div>
<p>This example will produce the playlist, <samp>out.m3u8</samp>, and segment files:
<samp>out0.ts</samp>, <samp>out1.ts</samp>, <samp>out2.ts</samp>, etc.
</p>
<p>See also the <a href="#segment">segment</a> muxer, which provides a more generic and
flexible implementation of a segmenter, and can be used to perform HLS
segmentation.
</p>
<a name="Options-9"></a>
<h4 class="subsection">4.17.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-9" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-9" aria-hidden="true">TOC</a></span></h4>
<p>This muxer supports the following options:
</p>
<dl compact="compact">
<dt><span><samp>hls_init_time <var>duration</var></samp></span></dt>
<dd><p>Set the initial target segment length. Default value is <var>0</var>.
</p>
<p><var>duration</var> must be a time duration specification,
see <a data-manual="ffmpeg-utils" href="ffmpeg-utils.html#time-duration-syntax">(ffmpeg-utils)the Time duration section in the ffmpeg-utils(1) manual</a>.
</p>
<p>Segment will be cut on the next key frame after this time has passed on the first m3u8 list.
After the initial playlist is filled <code>ffmpeg</code> will cut segments
at duration equal to <code>hls_time</code>
</p>
</dd>
<dt><span><samp>hls_time <var>duration</var></samp></span></dt>
<dd><p>Set the target segment length. Default value is 2.
</p>
<p><var>duration</var> must be a time duration specification,
see <a data-manual="ffmpeg-utils" href="ffmpeg-utils.html#time-duration-syntax">(ffmpeg-utils)the Time duration section in the ffmpeg-utils(1) manual</a>.
Segment will be cut on the next key frame after this time has passed.
</p>
</dd>
<dt><span><samp>hls_list_size <var>size</var></samp></span></dt>
<dd><p>Set the maximum number of playlist entries. If set to 0 the list file
will contain all the segments. Default value is 5.
</p>
</dd>
<dt><span><samp>hls_delete_threshold <var>size</var></samp></span></dt>
<dd><p>Set the number of unreferenced segments to keep on disk before <code>hls_flags delete_segments</code>
deletes them. Increase this to allow continue clients to download segments which
were recently referenced in the playlist. Default value is 1, meaning segments older than
<code>hls_list_size+1</code> will be deleted.
</p>
</dd>
<dt><span><samp>hls_ts_options <var>options_list</var></samp></span></dt>
<dd><p>Set output format options using a :-separated list of key=value
parameters. Values containing <code>:</code> special characters must be
escaped.
<code>hls_ts_options</code> is deprecated, use hls_segment_options instead of it..
</p>
</dd>
<dt><span><samp>hls_start_number_source</samp></span></dt>
<dd><p>Start the playlist sequence number (<code>#EXT-X-MEDIA-SEQUENCE</code>) according to the specified source.
Unless <code>hls_flags single_file</code> is set, it also specifies source of starting sequence numbers of
segment and subtitle filenames. In any case, if <code>hls_flags append_list</code>
is set and read playlist sequence number is greater than the specified start sequence number,
then that value will be used as start value.
</p>
<p>It accepts the following values:
</p>
<dl compact="compact">
<dt><span><samp>generic (default)</samp></span></dt>
<dd><p>Set the starting sequence numbers according to <var>start_number</var> option value.
</p>
</dd>
<dt><span><samp>epoch</samp></span></dt>
<dd><p>The start number will be the seconds since epoch (1970-01-01 00:00:00)
</p>
</dd>
<dt><span><samp>epoch_us</samp></span></dt>
<dd><p>The start number will be the microseconds since epoch (1970-01-01 00:00:00)
</p>
</dd>
<dt><span><samp>datetime</samp></span></dt>
<dd><p>The start number will be based on the current date/time as YYYYmmddHHMMSS. e.g. 20161231235759.
</p>
</dd>
</dl>
</dd>
<dt><span><samp>start_number <var>number</var></samp></span></dt>
<dd><p>Start the playlist sequence number (<code>#EXT-X-MEDIA-SEQUENCE</code>) from the specified <var>number</var>
when <var>hls_start_number_source</var> value is <var>generic</var>. (This is the default case.)
Unless <code>hls_flags single_file</code> is set, it also specifies starting sequence numbers of segment and subtitle filenames.
Default value is 0.
</p>
</dd>
<dt><span><samp>hls_allow_cache <var>allowcache</var></samp></span></dt>
<dd><p>Explicitly set whether the client MAY (1) or MUST NOT (0) cache media segments.
</p>
</dd>
<dt><span><samp>hls_base_url <var>baseurl</var></samp></span></dt>
<dd><p>Append <var>baseurl</var> to every entry in the playlist.
Useful to generate playlists with absolute paths.
</p>
<p>Note that the playlist sequence number must be unique for each segment
and it is not to be confused with the segment filename sequence number
which can be cyclic, for example if the <samp>wrap</samp> option is
specified.
</p>
</dd>
<dt><span><samp>hls_segment_filename <var>filename</var></samp></span></dt>
<dd><p>Set the segment filename. Unless <code>hls_flags single_file</code> is set,
<var>filename</var> is used as a string format with the segment number:
</p><div class="example">
<pre class="example">ffmpeg -i in.nut -hls_segment_filename 'file%03d.ts' out.m3u8
</pre></div>
<p>This example will produce the playlist, <samp>out.m3u8</samp>, and segment files:
<samp>file000.ts</samp>, <samp>file001.ts</samp>, <samp>file002.ts</samp>, etc.
</p>
<p><var>filename</var> may contain full path or relative path specification,
but only the file name part without any path info will be contained in the m3u8 segment list.
Should a relative path be specified, the path of the created segment
files will be relative to the current working directory.
When strftime_mkdir is set, the whole expanded value of <var>filename</var> will be written into the m3u8 segment list.
</p>
<p>When <code>var_stream_map</code> is set with two or more variant streams, the
<var>filename</var> pattern must contain the string "%v", this string specifies
the position of variant stream index in the generated segment file names.
</p><div class="example">
<pre class="example">ffmpeg -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
-map 0:v -map 0:a -map 0:v -map 0:a -f hls -var_stream_map "v:0,a:0 v:1,a:1" \
-hls_segment_filename 'file_%v_%03d.ts' out_%v.m3u8
</pre></div>
<p>This example will produce the playlists segment file sets:
<samp>file_0_000.ts</samp>, <samp>file_0_001.ts</samp>, <samp>file_0_002.ts</samp>, etc. and
<samp>file_1_000.ts</samp>, <samp>file_1_001.ts</samp>, <samp>file_1_002.ts</samp>, etc.
</p>
<p>The string "%v" may be present in the filename or in the last directory name
containing the file, but only in one of them. (Additionally, %v may appear multiple times in the last
sub-directory or filename.) If the string %v is present in the directory name, then
sub-directories are created after expanding the directory name pattern. This
enables creation of segments corresponding to different variant streams in
subdirectories.
</p><div class="example">
<pre class="example">ffmpeg -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
-map 0:v -map 0:a -map 0:v -map 0:a -f hls -var_stream_map "v:0,a:0 v:1,a:1" \
-hls_segment_filename 'vs%v/file_%03d.ts' vs%v/out.m3u8
</pre></div>
<p>This example will produce the playlists segment file sets:
<samp>vs0/file_000.ts</samp>, <samp>vs0/file_001.ts</samp>, <samp>vs0/file_002.ts</samp>, etc. and
<samp>vs1/file_000.ts</samp>, <samp>vs1/file_001.ts</samp>, <samp>vs1/file_002.ts</samp>, etc.
</p>
</dd>
<dt><span><samp>strftime</samp></span></dt>
<dd><p>Use strftime() on <var>filename</var> to expand the segment filename with localtime.
The segment number is also available in this mode, but to use it, you need to specify second_level_segment_index
hls_flag and %%d will be the specifier.
</p><div class="example">
<pre class="example">ffmpeg -i in.nut -strftime 1 -hls_segment_filename 'file-%Y%m%d-%s.ts' out.m3u8
</pre></div>
<p>This example will produce the playlist, <samp>out.m3u8</samp>, and segment files:
<samp>file-20160215-1455569023.ts</samp>, <samp>file-20160215-1455569024.ts</samp>, etc.
Note: On some systems/environments, the <code>%s</code> specifier is not available. See
<code>strftime()</code> documentation.
</p><div class="example">
<pre class="example">ffmpeg -i in.nut -strftime 1 -hls_flags second_level_segment_index -hls_segment_filename 'file-%Y%m%d-%%04d.ts' out.m3u8
</pre></div>
<p>This example will produce the playlist, <samp>out.m3u8</samp>, and segment files:
<samp>file-20160215-0001.ts</samp>, <samp>file-20160215-0002.ts</samp>, etc.
</p>
</dd>
<dt><span><samp>strftime_mkdir</samp></span></dt>
<dd><p>Used together with -strftime_mkdir, it will create all subdirectories which
is expanded in <var>filename</var>.
</p><div class="example">
<pre class="example">ffmpeg -i in.nut -strftime 1 -strftime_mkdir 1 -hls_segment_filename '%Y%m%d/file-%Y%m%d-%s.ts' out.m3u8
</pre></div>
<p>This example will create a directory 201560215 (if it does not exist), and then
produce the playlist, <samp>out.m3u8</samp>, and segment files:
<samp>20160215/file-20160215-1455569023.ts</samp>, <samp>20160215/file-20160215-1455569024.ts</samp>, etc.
</p>
<div class="example">
<pre class="example">ffmpeg -i in.nut -strftime 1 -strftime_mkdir 1 -hls_segment_filename '%Y/%m/%d/file-%Y%m%d-%s.ts' out.m3u8
</pre></div>
<p>This example will create a directory hierarchy 2016/02/15 (if any of them do not exist), and then
produce the playlist, <samp>out.m3u8</samp>, and segment files:
<samp>2016/02/15/file-20160215-1455569023.ts</samp>, <samp>2016/02/15/file-20160215-1455569024.ts</samp>, etc.
</p>
</dd>
<dt><span><samp>hls_segment_options <var>options_list</var></samp></span></dt>
<dd><p>Set output format options using a :-separated list of key=value
parameters. Values containing <code>:</code> special characters must be
escaped.
</p>
</dd>
<dt><span><samp>hls_key_info_file <var>key_info_file</var></samp></span></dt>
<dd><p>Use the information in <var>key_info_file</var> for segment encryption. The first
line of <var>key_info_file</var> specifies the key URI written to the playlist. The
key URL is used to access the encryption key during playback. The second line
specifies the path to the key file used to obtain the key during the encryption
process. The key file is read as a single packed array of 16 octets in binary
format. The optional third line specifies the initialization vector (IV) as a
hexadecimal string to be used instead of the segment sequence number (default)
for encryption. Changes to <var>key_info_file</var> will result in segment
encryption with the new key/IV and an entry in the playlist for the new key
URI/IV if <code>hls_flags periodic_rekey</code> is enabled.
</p>
<p>Key info file format:
</p><div class="example">
<pre class="example"><var>key URI</var>
<var>key file path</var>
<var>IV</var> (optional)
</pre></div>
<p>Example key URIs:
</p><div class="example">
<pre class="example">http://server/file.key
/path/to/file.key
file.key
</pre></div>
<p>Example key file paths:
</p><div class="example">
<pre class="example">file.key
/path/to/file.key
</pre></div>
<p>Example IV:
</p><div class="example">
<pre class="example">0123456789ABCDEF0123456789ABCDEF
</pre></div>
<p>Key info file example:
</p><div class="example">
<pre class="example">http://server/file.key
/path/to/file.key
0123456789ABCDEF0123456789ABCDEF
</pre></div>
<p>Example shell script:
</p><div class="example">
<pre class="example">#!/bin/sh
BASE_URL=${1:-'.'}
openssl rand 16 > file.key
echo $BASE_URL/file.key > file.keyinfo
echo file.key >> file.keyinfo
echo $(openssl rand -hex 16) >> file.keyinfo
ffmpeg -f lavfi -re -i testsrc -c:v h264 -hls_flags delete_segments \
-hls_key_info_file file.keyinfo out.m3u8
</pre></div>
</dd>
<dt><span><samp>-hls_enc <var>enc</var></samp></span></dt>
<dd><p>Enable (1) or disable (0) the AES128 encryption.
When enabled every segment generated is encrypted and the encryption key
is saved as <var>playlist name</var>.key.
</p>
</dd>
<dt><span><samp>-hls_enc_key <var>key</var></samp></span></dt>
<dd><p>16-octet key to encrypt the segments, by default it
is randomly generated.
</p>
</dd>
<dt><span><samp>-hls_enc_key_url <var>keyurl</var></samp></span></dt>
<dd><p>If set, <var>keyurl</var> is prepended instead of <var>baseurl</var> to the key filename
in the playlist.
</p>
</dd>
<dt><span><samp>-hls_enc_iv <var>iv</var></samp></span></dt>
<dd><p>16-octet initialization vector for every segment instead
of the autogenerated ones.
</p>
</dd>
<dt><span><samp>hls_segment_type <var>flags</var></samp></span></dt>
<dd><p>Possible values:
</p>
<dl compact="compact">
<dt><span>‘<samp>mpegts</samp>’</span></dt>
<dd><p>Output segment files in MPEG-2 Transport Stream format. This is
compatible with all HLS versions.
</p>
</dd>
<dt><span>‘<samp>fmp4</samp>’</span></dt>
<dd><p>Output segment files in fragmented MP4 format, similar to MPEG-DASH.
fmp4 files may be used in HLS version 7 and above.
</p>
</dd>
</dl>
</dd>
<dt><span><samp>hls_fmp4_init_filename <var>filename</var></samp></span></dt>
<dd><p>Set filename to the fragment files header file, default filename is <samp>init.mp4</samp>.
</p>
<p>Use <code>-strftime 1</code> on <var>filename</var> to expand the segment filename with localtime.
</p><div class="example">
<pre class="example">ffmpeg -i in.nut -hls_segment_type fmp4 -strftime 1 -hls_fmp4_init_filename "%s_init.mp4" out.m3u8
</pre></div>
<p>This will produce init like this
<samp>1602678741_init.mp4</samp>
</p>
</dd>
<dt><span><samp>hls_fmp4_init_resend</samp></span></dt>
<dd><p>Resend init file after m3u8 file refresh every time, default is <var>0</var>.
</p>
<p>When <code>var_stream_map</code> is set with two or more variant streams, the
<var>filename</var> pattern must contain the string "%v", this string specifies
the position of variant stream index in the generated init file names.
The string "%v" may be present in the filename or in the last directory name
containing the file. If the string is present in the directory name, then
sub-directories are created after expanding the directory name pattern. This
enables creation of init files corresponding to different variant streams in
subdirectories.
</p>
</dd>
<dt><span><samp>hls_flags <var>flags</var></samp></span></dt>
<dd><p>Possible values:
</p>
<dl compact="compact">
<dt><span>‘<samp>single_file</samp>’</span></dt>
<dd><p>If this flag is set, the muxer will store all segments in a single MPEG-TS
file, and will use byte ranges in the playlist. HLS playlists generated with
this way will have the version number 4.
For example:
</p><div class="example">
<pre class="example">ffmpeg -i in.nut -hls_flags single_file out.m3u8
</pre></div>
<p>Will produce the playlist, <samp>out.m3u8</samp>, and a single segment file,
<samp>out.ts</samp>.
</p>
</dd>
<dt><span>‘<samp>delete_segments</samp>’</span></dt>
<dd><p>Segment files removed from the playlist are deleted after a period of time
equal to the duration of the segment plus the duration of the playlist.
</p>
</dd>
<dt><span>‘<samp>append_list</samp>’</span></dt>
<dd><p>Append new segments into the end of old segment list,
and remove the <code>#EXT-X-ENDLIST</code> from the old segment list.
</p>
</dd>
<dt><span>‘<samp>round_durations</samp>’</span></dt>
<dd><p>Round the duration info in the playlist file segment info to integer
values, instead of using floating point.
If there are no other features requiring higher HLS versions be used,
then this will allow ffmpeg to output a HLS version 2 m3u8.
</p>
</dd>
<dt><span>‘<samp>discont_start</samp>’</span></dt>
<dd><p>Add the <code>#EXT-X-DISCONTINUITY</code> tag to the playlist, before the
first segment’s information.
</p>
</dd>
<dt><span>‘<samp>omit_endlist</samp>’</span></dt>
<dd><p>Do not append the <code>EXT-X-ENDLIST</code> tag at the end of the playlist.
</p>
</dd>
<dt><span>‘<samp>periodic_rekey</samp>’</span></dt>
<dd><p>The file specified by <code>hls_key_info_file</code> will be checked periodically and
detect updates to the encryption info. Be sure to replace this file atomically,
including the file containing the AES encryption key.
</p>
</dd>
<dt><span>‘<samp>independent_segments</samp>’</span></dt>
<dd><p>Add the <code>#EXT-X-INDEPENDENT-SEGMENTS</code> to playlists that has video segments
and when all the segments of that playlist are guaranteed to start with a Key frame.
</p>
</dd>
<dt><span>‘<samp>iframes_only</samp>’</span></dt>
<dd><p>Add the <code>#EXT-X-I-FRAMES-ONLY</code> to playlists that has video segments
and can play only I-frames in the <code>#EXT-X-BYTERANGE</code> mode.
</p>
</dd>
<dt><span>‘<samp>split_by_time</samp>’</span></dt>
<dd><p>Allow segments to start on frames other than keyframes. This improves
behavior on some players when the time between keyframes is inconsistent,
but may make things worse on others, and can cause some oddities during
seeking. This flag should be used with the <code>hls_time</code> option.
</p>
</dd>
<dt><span>‘<samp>program_date_time</samp>’</span></dt>
<dd><p>Generate <code>EXT-X-PROGRAM-DATE-TIME</code> tags.
</p>
</dd>
<dt><span>‘<samp>second_level_segment_index</samp>’</span></dt>
<dd><p>Makes it possible to use segment indexes as %%d in hls_segment_filename expression
besides date/time values when strftime is on.
To get fixed width numbers with trailing zeroes, %%0xd format is available where x is the required width.
</p>
</dd>
<dt><span>‘<samp>second_level_segment_size</samp>’</span></dt>
<dd><p>Makes it possible to use segment sizes (counted in bytes) as %%s in hls_segment_filename
expression besides date/time values when strftime is on.
To get fixed width numbers with trailing zeroes, %%0xs format is available where x is the required width.
</p>
</dd>
<dt><span>‘<samp>second_level_segment_duration</samp>’</span></dt>
<dd><p>Makes it possible to use segment duration (calculated in microseconds) as %%t in hls_segment_filename
expression besides date/time values when strftime is on.
To get fixed width numbers with trailing zeroes, %%0xt format is available where x is the required width.
</p>
<div class="example">
<pre class="example">ffmpeg -i sample.mpeg \
-f hls -hls_time 3 -hls_list_size 5 \
-hls_flags second_level_segment_index+second_level_segment_size+second_level_segment_duration \
-strftime 1 -strftime_mkdir 1 -hls_segment_filename "segment_%Y%m%d%H%M%S_%%04d_%%08s_%%013t.ts" stream.m3u8
</pre></div>
<p>This will produce segments like this:
<samp>segment_20170102194334_0003_00122200_0000003000000.ts</samp>, <samp>segment_20170102194334_0004_00120072_0000003000000.ts</samp> etc.
</p>
</dd>
<dt><span>‘<samp>temp_file</samp>’</span></dt>
<dd><p>Write segment data to filename.tmp and rename to filename only once the segment is complete. A webserver
serving up segments can be configured to reject requests to *.tmp to prevent access to in-progress segments
before they have been added to the m3u8 playlist. This flag also affects how m3u8 playlist files are created.
If this flag is set, all playlist files will written into temporary file and renamed after they are complete, similarly as segments are handled.
But playlists with <code>file</code> protocol and with type (<code>hls_playlist_type</code>) other than <code>vod</code>
are always written into temporary file regardless of this flag. Master playlist files (<code>master_pl_name</code>), if any, with <code>file</code> protocol,
are always written into temporary file regardless of this flag if <code>master_pl_publish_rate</code> value is other than zero.
</p>
</dd>
</dl>
</dd>
<dt><span><samp>hls_playlist_type event</samp></span></dt>
<dd><p>Emit <code>#EXT-X-PLAYLIST-TYPE:EVENT</code> in the m3u8 header. Forces
<samp>hls_list_size</samp> to 0; the playlist can only be appended to.
</p>
</dd>
<dt><span><samp>hls_playlist_type vod</samp></span></dt>
<dd><p>Emit <code>#EXT-X-PLAYLIST-TYPE:VOD</code> in the m3u8 header. Forces
<samp>hls_list_size</samp> to 0; the playlist must not change.
</p>
</dd>
<dt><span><samp>method</samp></span></dt>
<dd><p>Use the given HTTP method to create the hls files.
</p><div class="example">
<pre class="example">ffmpeg -re -i in.ts -f hls -method PUT http://example.com/live/out.m3u8
</pre></div>
<p>This example will upload all the mpegts segment files to the HTTP
server using the HTTP PUT method, and update the m3u8 files every
<code>refresh</code> times using the same method.
Note that the HTTP server must support the given method for uploading
files.
</p>
</dd>
<dt><span><samp>http_user_agent</samp></span></dt>
<dd><p>Override User-Agent field in HTTP header. Applicable only for HTTP output.
</p>
</dd>
<dt><span><samp>var_stream_map</samp></span></dt>
<dd><p>Map string which specifies how to group the audio, video and subtitle streams
into different variant streams. The variant stream groups are separated
by space.
Expected string format is like this "a:0,v:0 a:1,v:1 ....". Here a:, v:, s: are
the keys to specify audio, video and subtitle streams respectively.
Allowed values are 0 to 9 (limited just based on practical usage).
</p>
<p>When there are two or more variant streams, the output filename pattern must
contain the string "%v", this string specifies the position of variant stream
index in the output media playlist filenames. The string "%v" may be present in
the filename or in the last directory name containing the file. If the string is
present in the directory name, then sub-directories are created after expanding
the directory name pattern. This enables creation of variant streams in
subdirectories.
</p>
<div class="example">
<pre class="example">ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
-map 0:v -map 0:a -map 0:v -map 0:a -f hls -var_stream_map "v:0,a:0 v:1,a:1" \
http://example.com/live/out_%v.m3u8
</pre></div>
<p>This example creates two hls variant streams. The first variant stream will
contain video stream of bitrate 1000k and audio stream of bitrate 64k and the
second variant stream will contain video stream of bitrate 256k and audio
stream of bitrate 32k. Here, two media playlist with file names out_0.m3u8 and
out_1.m3u8 will be created. If you want something meaningful text instead of indexes
in result names, you may specify names for each or some of the variants
as in the following example.
</p>
<div class="example">
<pre class="example">ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
-map 0:v -map 0:a -map 0:v -map 0:a -f hls -var_stream_map "v:0,a:0,name:my_hd v:1,a:1,name:my_sd" \
http://example.com/live/out_%v.m3u8
</pre></div>
<p>This example creates two hls variant streams as in the previous one.
But here, the two media playlist with file names out_my_hd.m3u8 and
out_my_sd.m3u8 will be created.
</p>
<div class="example">
<pre class="example">ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k \
-map 0:v -map 0:a -map 0:v -f hls -var_stream_map "v:0 a:0 v:1" \
http://example.com/live/out_%v.m3u8
</pre></div>
<p>This example creates three hls variant streams. The first variant stream will
be a video only stream with video bitrate 1000k, the second variant stream will
be an audio only stream with bitrate 64k and the third variant stream will be a
video only stream with bitrate 256k. Here, three media playlist with file names
out_0.m3u8, out_1.m3u8 and out_2.m3u8 will be created.
</p><div class="example">
<pre class="example">ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
-map 0:v -map 0:a -map 0:v -map 0:a -f hls -var_stream_map "v:0,a:0 v:1,a:1" \
http://example.com/live/vs_%v/out.m3u8
</pre></div>
<p>This example creates the variant streams in subdirectories. Here, the first
media playlist is created at <samp>http://example.com/live/vs_0/out.m3u8</samp> and
the second one at <samp>http://example.com/live/vs_1/out.m3u8</samp>.
</p><div class="example">
<pre class="example">ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k -b:v:1 3000k \
-map 0:a -map 0:a -map 0:v -map 0:v -f hls \
-var_stream_map "a:0,agroup:aud_low a:1,agroup:aud_high v:0,agroup:aud_low v:1,agroup:aud_high" \
-master_pl_name master.m3u8 \
http://example.com/live/out_%v.m3u8
</pre></div>
<p>This example creates two audio only and two video only variant streams. In
addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
and they are mapped to the two video only variant streams with audio group names
’aud_low’ and ’aud_high’.
</p>
<p>By default, a single hls variant containing all the encoded streams is created.
</p>
<div class="example">
<pre class="example">ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k \
-map 0:a -map 0:a -map 0:v -f hls \
-var_stream_map "a:0,agroup:aud_low,default:yes a:1,agroup:aud_low v:0,agroup:aud_low" \
-master_pl_name master.m3u8 \
http://example.com/live/out_%v.m3u8
</pre></div>
<p>This example creates two audio only and one video only variant streams. In
addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
and they are mapped to the one video only variant streams with audio group name
’aud_low’, and the audio group have default stat is NO or YES.
</p>
<p>By default, a single hls variant containing all the encoded streams is created.
</p>
<div class="example">
<pre class="example">ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k \
-map 0:a -map 0:a -map 0:v -f hls \
-var_stream_map "a:0,agroup:aud_low,default:yes,language:ENG a:1,agroup:aud_low,language:CHN v:0,agroup:aud_low" \
-master_pl_name master.m3u8 \
http://example.com/live/out_%v.m3u8
</pre></div>
<p>This example creates two audio only and one video only variant streams. In
addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
and they are mapped to the one video only variant streams with audio group name
’aud_low’, and the audio group have default stat is NO or YES, and one audio
have and language is named ENG, the other audio language is named CHN.
</p>
<p>By default, a single hls variant containing all the encoded streams is created.
</p>
<div class="example">
<pre class="example">ffmpeg -y -i input_with_subtitle.mkv \
-b:v:0 5250k -c:v h264 -pix_fmt yuv420p -profile:v main -level 4.1 \
-b:a:0 256k \
-c:s webvtt -c:a mp2 -ar 48000 -ac 2 -map 0:v -map 0:a:0 -map 0:s:0 \
-f hls -var_stream_map "v:0,a:0,s:0,sgroup:subtitle" \
-master_pl_name master.m3u8 -t 300 -hls_time 10 -hls_init_time 4 -hls_list_size \
10 -master_pl_publish_rate 10 -hls_flags \
delete_segments+discont_start+split_by_time ./tmp/video.m3u8
</pre></div>
<p>This example adds <code>#EXT-X-MEDIA</code> tag with <code>TYPE=SUBTITLES</code> in
the master playlist with webvtt subtitle group name ’subtitle’. Please make sure
the input file has one text subtitle stream at least.
</p>
</dd>
<dt><span><samp>cc_stream_map</samp></span></dt>
<dd><p>Map string which specifies different closed captions groups and their
attributes. The closed captions stream groups are separated by space.
Expected string format is like this
"ccgroup:<group name>,instreamid:<INSTREAM-ID>,language:<language code> ....".
’ccgroup’ and ’instreamid’ are mandatory attributes. ’language’ is an optional
attribute.
The closed captions groups configured using this option are mapped to different
variant streams by providing the same ’ccgroup’ name in the
<code>var_stream_map</code> string. If <code>var_stream_map</code> is not set, then the
first available ccgroup in <code>cc_stream_map</code> is mapped to the output variant
stream. The examples for these two use cases are given below.
</p>
<div class="example">
<pre class="example">ffmpeg -re -i in.ts -b:v 1000k -b:a 64k -a53cc 1 -f hls \
-cc_stream_map "ccgroup:cc,instreamid:CC1,language:en" \
-master_pl_name master.m3u8 \
http://example.com/live/out.m3u8
</pre></div>
<p>This example adds <code>#EXT-X-MEDIA</code> tag with <code>TYPE=CLOSED-CAPTIONS</code> in
the master playlist with group name ’cc’, language ’en’ (english) and
INSTREAM-ID ’CC1’. Also, it adds <code>CLOSED-CAPTIONS</code> attribute with group
name ’cc’ for the output variant stream.
</p><div class="example">
<pre class="example">ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
-a53cc:0 1 -a53cc:1 1\
-map 0:v -map 0:a -map 0:v -map 0:a -f hls \
-cc_stream_map "ccgroup:cc,instreamid:CC1,language:en ccgroup:cc,instreamid:CC2,language:sp" \
-var_stream_map "v:0,a:0,ccgroup:cc v:1,a:1,ccgroup:cc" \
-master_pl_name master.m3u8 \
http://example.com/live/out_%v.m3u8
</pre></div>
<p>This example adds two <code>#EXT-X-MEDIA</code> tags with <code>TYPE=CLOSED-CAPTIONS</code> in
the master playlist for the INSTREAM-IDs ’CC1’ and ’CC2’. Also, it adds
<code>CLOSED-CAPTIONS</code> attribute with group name ’cc’ for the two output variant
streams.
</p>
</dd>
<dt><span><samp>master_pl_name</samp></span></dt>
<dd><p>Create HLS master playlist with the given name.
</p>
<div class="example">
<pre class="example">ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 http://example.com/live/out.m3u8
</pre></div>
<p>This example creates HLS master playlist with name master.m3u8 and it is
published at http://example.com/live/
</p>
</dd>
<dt><span><samp>master_pl_publish_rate</samp></span></dt>
<dd><p>Publish master play list repeatedly every after specified number of segment intervals.
</p>
<div class="example">
<pre class="example">ffmpeg -re -i in.ts -f hls -master_pl_name master.m3u8 \
-hls_time 2 -master_pl_publish_rate 30 http://example.com/live/out.m3u8
</pre></div>
<p>This example creates HLS master playlist with name master.m3u8 and keep
publishing it repeatedly every after 30 segments i.e. every after 60s.
</p>
</dd>
<dt><span><samp>http_persistent</samp></span></dt>
<dd><p>Use persistent HTTP connections. Applicable only for HTTP output.
</p>
</dd>
<dt><span><samp>timeout</samp></span></dt>
<dd><p>Set timeout for socket I/O operations. Applicable only for HTTP output.
</p>
</dd>
<dt><span><samp>-ignore_io_errors</samp></span></dt>
<dd><p>Ignore IO errors during open, write and delete. Useful for long-duration runs with network output.
</p>
</dd>
<dt><span><samp>headers</samp></span></dt>
<dd><p>Set custom HTTP headers, can override built in default headers. Applicable only for HTTP output.
</p>
</dd>
</dl>
<span id="ico"></span><a name="ico-1"></a>
<h3 class="section">4.18 ico<span class="pull-right"><a class="anchor hidden-xs" href="#ico-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-ico-1" aria-hidden="true">TOC</a></span></h3>
<p>ICO file muxer.
</p>
<p>Microsoft’s icon file format (ICO) has some strict limitations that should be noted:
</p>
<ul>
<li> Size cannot exceed 256 pixels in any dimension
</li><li> Only BMP and PNG images can be stored
</li><li> If a BMP image is used, it must be one of the following pixel formats:
<div class="example">
<pre class="example">BMP Bit Depth FFmpeg Pixel Format
1bit pal8
4bit pal8
8bit pal8
16bit rgb555le
24bit bgr24
32bit bgra
</pre></div>
</li><li> If a BMP image is used, it must use the BITMAPINFOHEADER DIB header
</li><li> If a PNG image is used, it must use the rgba pixel format
</li></ul>
<span id="image2"></span><a name="image2-2"></a>
<h3 class="section">4.19 image2<span class="pull-right"><a class="anchor hidden-xs" href="#image2-2" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-image2-2" aria-hidden="true">TOC</a></span></h3>
<p>Image file muxer.
</p>
<p>The image file muxer writes video frames to image files.
</p>
<p>The output filenames are specified by a pattern, which can be used to
produce sequentially numbered series of files.
The pattern may contain the string "%d" or "%0<var>N</var>d", this string
specifies the position of the characters representing a numbering in
the filenames. If the form "%0<var>N</var>d" is used, the string
representing the number in each filename is 0-padded to <var>N</var>
digits. The literal character ’%’ can be specified in the pattern with
the string "%%".
</p>
<p>If the pattern contains "%d" or "%0<var>N</var>d", the first filename of
the file list specified will contain the number 1, all the following
numbers will be sequential.
</p>
<p>The pattern may contain a suffix which is used to automatically
determine the format of the image files to write.
</p>
<p>For example the pattern "img-%03d.bmp" will specify a sequence of
filenames of the form <samp>img-001.bmp</samp>, <samp>img-002.bmp</samp>, ...,
<samp>img-010.bmp</samp>, etc.
The pattern "img%%-%d.jpg" will specify a sequence of filenames of the
form <samp>img%-1.jpg</samp>, <samp>img%-2.jpg</samp>, ..., <samp>img%-10.jpg</samp>,
etc.
</p>
<p>The image muxer supports the .Y.U.V image file format. This format is
special in that that each image frame consists of three files, for
each of the YUV420P components. To read or write this image file format,
specify the name of the ’.Y’ file. The muxer will automatically open the
’.U’ and ’.V’ files as required.
</p>
<a name="Options-10"></a>
<h4 class="subsection">4.19.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-10" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-10" aria-hidden="true">TOC</a></span></h4>
<dl compact="compact">
<dt><span><samp>frame_pts</samp></span></dt>
<dd><p>If set to 1, expand the filename with pts from pkt->pts.
Default value is 0.
</p>
</dd>
<dt><span><samp>start_number</samp></span></dt>
<dd><p>Start the sequence from the specified number. Default value is 1.
</p>
</dd>
<dt><span><samp>update</samp></span></dt>
<dd><p>If set to 1, the filename will always be interpreted as just a
filename, not a pattern, and the corresponding file will be continuously
overwritten with new images. Default value is 0.
</p>
</dd>
<dt><span><samp>strftime</samp></span></dt>
<dd><p>If set to 1, expand the filename with date and time information from
<code>strftime()</code>. Default value is 0.
</p>
</dd>
<dt><span><samp>atomic_writing</samp></span></dt>
<dd><p>Write output to a temporary file, which is renamed to target filename once
writing is completed. Default is disabled.
</p>
</dd>
<dt><span><samp>protocol_opts <var>options_list</var></samp></span></dt>
<dd><p>Set protocol options as a :-separated list of key=value parameters. Values
containing the <code>:</code> special character must be escaped.
</p>
</dd>
</dl>
<a name="Examples-8"></a>
<h4 class="subsection">4.19.2 Examples<span class="pull-right"><a class="anchor hidden-xs" href="#Examples-8" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Examples-8" aria-hidden="true">TOC</a></span></h4>
<p>The following example shows how to use <code>ffmpeg</code> for creating a
sequence of files <samp>img-001.jpeg</samp>, <samp>img-002.jpeg</samp>, ...,
taking one image every second from the input video:
</p><div class="example">
<pre class="example">ffmpeg -i in.avi -vsync cfr -r 1 -f image2 'img-%03d.jpeg'
</pre></div>
<p>Note that with <code>ffmpeg</code>, if the format is not specified with the
<code>-f</code> option and the output filename specifies an image file
format, the image2 muxer is automatically selected, so the previous
command can be written as:
</p><div class="example">
<pre class="example">ffmpeg -i in.avi -vsync cfr -r 1 'img-%03d.jpeg'
</pre></div>
<p>Note also that the pattern must not necessarily contain "%d" or
"%0<var>N</var>d", for example to create a single image file
<samp>img.jpeg</samp> from the start of the input video you can employ the command:
</p><div class="example">
<pre class="example">ffmpeg -i in.avi -f image2 -frames:v 1 img.jpeg
</pre></div>
<p>The <samp>strftime</samp> option allows you to expand the filename with
date and time information. Check the documentation of
the <code>strftime()</code> function for the syntax.
</p>
<p>For example to generate image files from the <code>strftime()</code>
"%Y-%m-%d_%H-%M-%S" pattern, the following <code>ffmpeg</code> command
can be used:
</p><div class="example">
<pre class="example">ffmpeg -f v4l2 -r 1 -i /dev/video0 -f image2 -strftime 1 "%Y-%m-%d_%H-%M-%S.jpg"
</pre></div>
<p>You can set the file name with current frame’s PTS:
</p><div class="example">
<pre class="example">ffmpeg -f v4l2 -r 1 -i /dev/video0 -copyts -f image2 -frame_pts true %d.jpg"
</pre></div>
<p>A more complex example is to publish contents of your desktop directly to a
WebDAV server every second:
</p><div class="example">
<pre class="example">ffmpeg -f x11grab -framerate 1 -i :0.0 -q:v 6 -update 1 -protocol_opts method=PUT http://example.com/desktop.jpg
</pre></div>
<a name="matroska"></a>
<h3 class="section">4.20 matroska<span class="pull-right"><a class="anchor hidden-xs" href="#matroska" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-matroska" aria-hidden="true">TOC</a></span></h3>
<p>Matroska container muxer.
</p>
<p>This muxer implements the matroska and webm container specs.
</p>
<a name="Metadata"></a>
<h4 class="subsection">4.20.1 Metadata<span class="pull-right"><a class="anchor hidden-xs" href="#Metadata" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Metadata" aria-hidden="true">TOC</a></span></h4>
<p>The recognized metadata settings in this muxer are:
</p>
<dl compact="compact">
<dt><span><samp>title</samp></span></dt>
<dd><p>Set title name provided to a single track. This gets mapped to
the FileDescription element for a stream written as attachment.
</p>
</dd>
<dt><span><samp>language</samp></span></dt>
<dd><p>Specify the language of the track in the Matroska languages form.
</p>
<p>The language can be either the 3 letters bibliographic ISO-639-2 (ISO
639-2/B) form (like "fre" for French), or a language code mixed with a
country code for specialities in languages (like "fre-ca" for Canadian
French).
</p>
</dd>
<dt><span><samp>stereo_mode</samp></span></dt>
<dd><p>Set stereo 3D video layout of two views in a single video track.
</p>
<p>The following values are recognized:
</p><dl compact="compact">
<dt><span>‘<samp>mono</samp>’</span></dt>
<dd><p>video is not stereo
</p></dd>
<dt><span>‘<samp>left_right</samp>’</span></dt>
<dd><p>Both views are arranged side by side, Left-eye view is on the left
</p></dd>
<dt><span>‘<samp>bottom_top</samp>’</span></dt>
<dd><p>Both views are arranged in top-bottom orientation, Left-eye view is at bottom
</p></dd>
<dt><span>‘<samp>top_bottom</samp>’</span></dt>
<dd><p>Both views are arranged in top-bottom orientation, Left-eye view is on top
</p></dd>
<dt><span>‘<samp>checkerboard_rl</samp>’</span></dt>
<dd><p>Each view is arranged in a checkerboard interleaved pattern, Left-eye view being first
</p></dd>
<dt><span>‘<samp>checkerboard_lr</samp>’</span></dt>
<dd><p>Each view is arranged in a checkerboard interleaved pattern, Right-eye view being first
</p></dd>
<dt><span>‘<samp>row_interleaved_rl</samp>’</span></dt>
<dd><p>Each view is constituted by a row based interleaving, Right-eye view is first row
</p></dd>
<dt><span>‘<samp>row_interleaved_lr</samp>’</span></dt>
<dd><p>Each view is constituted by a row based interleaving, Left-eye view is first row
</p></dd>
<dt><span>‘<samp>col_interleaved_rl</samp>’</span></dt>
<dd><p>Both views are arranged in a column based interleaving manner, Right-eye view is first column
</p></dd>
<dt><span>‘<samp>col_interleaved_lr</samp>’</span></dt>
<dd><p>Both views are arranged in a column based interleaving manner, Left-eye view is first column
</p></dd>
<dt><span>‘<samp>anaglyph_cyan_red</samp>’</span></dt>
<dd><p>All frames are in anaglyph format viewable through red-cyan filters
</p></dd>
<dt><span>‘<samp>right_left</samp>’</span></dt>
<dd><p>Both views are arranged side by side, Right-eye view is on the left
</p></dd>
<dt><span>‘<samp>anaglyph_green_magenta</samp>’</span></dt>
<dd><p>All frames are in anaglyph format viewable through green-magenta filters
</p></dd>
<dt><span>‘<samp>block_lr</samp>’</span></dt>
<dd><p>Both eyes laced in one Block, Left-eye view is first
</p></dd>
<dt><span>‘<samp>block_rl</samp>’</span></dt>
<dd><p>Both eyes laced in one Block, Right-eye view is first
</p></dd>
</dl>
</dd>
</dl>
<p>For example a 3D WebM clip can be created using the following command line:
</p><div class="example">
<pre class="example">ffmpeg -i sample_left_right_clip.mpg -an -c:v libvpx -metadata stereo_mode=left_right -y stereo_clip.webm
</pre></div>
<a name="Options-11"></a>
<h4 class="subsection">4.20.2 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-11" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-11" aria-hidden="true">TOC</a></span></h4>
<p>This muxer supports the following options:
</p>
<dl compact="compact">
<dt><span><samp>reserve_index_space</samp></span></dt>
<dd><p>By default, this muxer writes the index for seeking (called cues in Matroska
terms) at the end of the file, because it cannot know in advance how much space
to leave for the index at the beginning of the file. However for some use cases
– e.g. streaming where seeking is possible but slow – it is useful to put the
index at the beginning of the file.
</p>
<p>If this option is set to a non-zero value, the muxer will reserve a given amount
of space in the file header and then try to write the cues there when the muxing
finishes. If the reserved space does not suffice, no Cues will be written, the
file will be finalized and writing the trailer will return an error.
A safe size for most use cases should be about 50kB per hour of video.
</p>
<p>Note that cues are only written if the output is seekable and this option will
have no effect if it is not.
</p>
</dd>
<dt><span><samp>cues_to_front</samp></span></dt>
<dd><p>If set, the muxer will write the index at the beginning of the file
by shifting the main data if necessary. This can be combined with
reserve_index_space in which case the data is only shifted if
the initially reserved space turns out to be insufficient.
</p>
<p>This option is ignored if the output is unseekable.
</p>
</dd>
<dt><span><samp>default_mode</samp></span></dt>
<dd><p>This option controls how the FlagDefault of the output tracks will be set.
It influences which tracks players should play by default. The default mode
is ‘<samp>passthrough</samp>’.
</p><dl compact="compact">
<dt><span>‘<samp>infer</samp>’</span></dt>
<dd><p>Every track with disposition default will have the FlagDefault set.
Additionally, for each type of track (audio, video or subtitle), if no track
with disposition default of this type exists, then the first track of this type
will be marked as default (if existing). This ensures that the default flag
is set in a sensible way even if the input originated from containers that
lack the concept of default tracks.
</p></dd>
<dt><span>‘<samp>infer_no_subs</samp>’</span></dt>
<dd><p>This mode is the same as infer except that if no subtitle track with
disposition default exists, no subtitle track will be marked as default.
</p></dd>
<dt><span>‘<samp>passthrough</samp>’</span></dt>
<dd><p>In this mode the FlagDefault is set if and only if the AV_DISPOSITION_DEFAULT
flag is set in the disposition of the corresponding stream.
</p></dd>
</dl>
</dd>
<dt><span><samp>flipped_raw_rgb</samp></span></dt>
<dd><p>If set to true, store positive height for raw RGB bitmaps, which indicates
bitmap is stored bottom-up. Note that this option does not flip the bitmap
which has to be done manually beforehand, e.g. by using the vflip filter.
Default is <var>false</var> and indicates bitmap is stored top down.
</p>
</dd>
</dl>
<span id="md5"></span><a name="md5-1"></a>
<h3 class="section">4.21 md5<span class="pull-right"><a class="anchor hidden-xs" href="#md5-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-md5-1" aria-hidden="true">TOC</a></span></h3>
<p>MD5 testing format.
</p>
<p>This is a variant of the <a href="#hash">hash</a> muxer. Unlike that muxer, it
defaults to using the MD5 hash function.
</p>
<a name="Examples-9"></a>
<h4 class="subsection">4.21.1 Examples<span class="pull-right"><a class="anchor hidden-xs" href="#Examples-9" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Examples-9" aria-hidden="true">TOC</a></span></h4>
<p>To compute the MD5 hash of the input converted to raw
audio and video, and store it in the file <samp>out.md5</samp>:
</p><div class="example">
<pre class="example">ffmpeg -i INPUT -f md5 out.md5
</pre></div>
<p>You can print the MD5 to stdout with the command:
</p><div class="example">
<pre class="example">ffmpeg -i INPUT -f md5 -
</pre></div>
<p>See also the <a href="#hash">hash</a> and <a href="#framemd5">framemd5</a> muxers.
</p>
<a name="mov_002c-mp4_002c-ismv"></a>
<h3 class="section">4.22 mov, mp4, ismv<span class="pull-right"><a class="anchor hidden-xs" href="#mov_002c-mp4_002c-ismv" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-mov_002c-mp4_002c-ismv" aria-hidden="true">TOC</a></span></h3>
<p>MOV/MP4/ISMV (Smooth Streaming) muxer.
</p>
<p>The mov/mp4/ismv muxer supports fragmentation. Normally, a MOV/MP4
file has all the metadata about all packets stored in one location
(written at the end of the file, it can be moved to the start for
better playback by adding <var>faststart</var> to the <var>movflags</var>, or
using the <code>qt-faststart</code> tool). A fragmented
file consists of a number of fragments, where packets and metadata
about these packets are stored together. Writing a fragmented
file has the advantage that the file is decodable even if the
writing is interrupted (while a normal MOV/MP4 is undecodable if
it is not properly finished), and it requires less memory when writing
very long files (since writing normal MOV/MP4 files stores info about
every single packet in memory until the file is closed). The downside
is that it is less compatible with other applications.
</p>
<a name="Options-12"></a>
<h4 class="subsection">4.22.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-12" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-12" aria-hidden="true">TOC</a></span></h4>
<p>Fragmentation is enabled by setting one of the AVOptions that define
how to cut the file into fragments:
</p>
<dl compact="compact">
<dt><span><samp>-moov_size <var>bytes</var></samp></span></dt>
<dd><p>Reserves space for the moov atom at the beginning of the file instead of placing the
moov atom at the end. If the space reserved is insufficient, muxing will fail.
</p></dd>
<dt><span><samp>-movflags frag_keyframe</samp></span></dt>
<dd><p>Start a new fragment at each video keyframe.
</p></dd>
<dt><span><samp>-frag_duration <var>duration</var></samp></span></dt>
<dd><p>Create fragments that are <var>duration</var> microseconds long.
</p></dd>
<dt><span><samp>-frag_size <var>size</var></samp></span></dt>
<dd><p>Create fragments that contain up to <var>size</var> bytes of payload data.
</p></dd>
<dt><span><samp>-movflags frag_custom</samp></span></dt>
<dd><p>Allow the caller to manually choose when to cut fragments, by
calling <code>av_write_frame(ctx, NULL)</code> to write a fragment with
the packets written so far. (This is only useful with other
applications integrating libavformat, not from <code>ffmpeg</code>.)
</p></dd>
<dt><span><samp>-min_frag_duration <var>duration</var></samp></span></dt>
<dd><p>Don’t create fragments that are shorter than <var>duration</var> microseconds long.
</p></dd>
</dl>
<p>If more than one condition is specified, fragments are cut when
one of the specified conditions is fulfilled. The exception to this is
<code>-min_frag_duration</code>, which has to be fulfilled for any of the other
conditions to apply.
</p>
<p>Additionally, the way the output file is written can be adjusted
through a few other options:
</p>
<dl compact="compact">
<dt><span><samp>-movflags empty_moov</samp></span></dt>
<dd><p>Write an initial moov atom directly at the start of the file, without
describing any samples in it. Generally, an mdat/moov pair is written
at the start of the file, as a normal MOV/MP4 file, containing only
a short portion of the file. With this option set, there is no initial
mdat atom, and the moov atom only describes the tracks but has
a zero duration.
</p>
<p>This option is implicitly set when writing ismv (Smooth Streaming) files.
</p></dd>
<dt><span><samp>-movflags separate_moof</samp></span></dt>
<dd><p>Write a separate moof (movie fragment) atom for each track. Normally,
packets for all tracks are written in a moof atom (which is slightly
more efficient), but with this option set, the muxer writes one moof/mdat
pair for each track, making it easier to separate tracks.
</p>
<p>This option is implicitly set when writing ismv (Smooth Streaming) files.
</p></dd>
<dt><span><samp>-movflags skip_sidx</samp></span></dt>
<dd><p>Skip writing of sidx atom. When bitrate overhead due to sidx atom is high,
this option could be used for cases where sidx atom is not mandatory.
When global_sidx flag is enabled, this option will be ignored.
</p></dd>
<dt><span><samp>-movflags faststart</samp></span></dt>
<dd><p>Run a second pass moving the index (moov atom) to the beginning of the file.
This operation can take a while, and will not work in various situations such
as fragmented output, thus it is not enabled by default.
</p></dd>
<dt><span><samp>-movflags rtphint</samp></span></dt>
<dd><p>Add RTP hinting tracks to the output file.
</p></dd>
<dt><span><samp>-movflags disable_chpl</samp></span></dt>
<dd><p>Disable Nero chapter markers (chpl atom). Normally, both Nero chapters
and a QuickTime chapter track are written to the file. With this option
set, only the QuickTime chapter track will be written. Nero chapters can
cause failures when the file is reprocessed with certain tagging programs, like
mp3Tag 2.61a and iTunes 11.3, most likely other versions are affected as well.
</p></dd>
<dt><span><samp>-movflags omit_tfhd_offset</samp></span></dt>
<dd><p>Do not write any absolute base_data_offset in tfhd atoms. This avoids
tying fragments to absolute byte positions in the file/streams.
</p></dd>
<dt><span><samp>-movflags default_base_moof</samp></span></dt>
<dd><p>Similarly to the omit_tfhd_offset, this flag avoids writing the
absolute base_data_offset field in tfhd atoms, but does so by using
the new default-base-is-moof flag instead. This flag is new from
14496-12:2012. This may make the fragments easier to parse in certain
circumstances (avoiding basing track fragment location calculations
on the implicit end of the previous track fragment).
</p></dd>
<dt><span><samp>-write_tmcd</samp></span></dt>
<dd><p>Specify <code>on</code> to force writing a timecode track, <code>off</code> to disable it
and <code>auto</code> to write a timecode track only for mov and mp4 output (default).
</p></dd>
<dt><span><samp>-movflags negative_cts_offsets</samp></span></dt>
<dd><p>Enables utilization of version 1 of the CTTS box, in which the CTS offsets can
be negative. This enables the initial sample to have DTS/CTS of zero, and
reduces the need for edit lists for some cases such as video tracks with
B-frames. Additionally, eases conformance with the DASH-IF interoperability
guidelines.
</p>
<p>This option is implicitly set when writing ismv (Smooth Streaming) files.
</p>
</dd>
<dt><span><samp>-write_btrt <var>bool</var></samp></span></dt>
<dd><p>Force or disable writing bitrate box inside stsd box of a track.
The box contains decoding buffer size (in bytes), maximum bitrate and
average bitrate for the track. The box will be skipped if none of these values
can be computed.
Default is <code>-1</code> or <code>auto</code>, which will write the box only in MP4 mode.
</p>
</dd>
<dt><span><samp>-write_prft</samp></span></dt>
<dd><p>Write producer time reference box (PRFT) with a specified time source for the
NTP field in the PRFT box. Set value as ‘<samp>wallclock</samp>’ to specify timesource
as wallclock time and ‘<samp>pts</samp>’ to specify timesource as input packets’ PTS
values.
</p>
<p>Setting value to ‘<samp>pts</samp>’ is applicable only for a live encoding use case,
where PTS values are set as as wallclock time at the source. For example, an
encoding use case with decklink capture source where <samp>video_pts</samp> and
<samp>audio_pts</samp> are set to ‘<samp>abs_wallclock</samp>’.
</p>
</dd>
<dt><span><samp>-empty_hdlr_name <var>bool</var></samp></span></dt>
<dd><p>Enable to skip writing the name inside a <code>hdlr</code> box.
Default is <code>false</code>.
</p>
</dd>
<dt><span><samp>-movie_timescale <var>scale</var></samp></span></dt>
<dd><p>Set the timescale written in the movie header box (<code>mvhd</code>).
Range is 1 to INT_MAX. Default is 1000.
</p>
</dd>
<dt><span><samp>-video_track_timescale <var>scale</var></samp></span></dt>
<dd><p>Set the timescale used for video tracks. Range is 0 to INT_MAX.
If set to <code>0</code>, the timescale is automatically set based on
the native stream time base. Default is 0.
</p></dd>
</dl>
<a name="Example"></a>
<h4 class="subsection">4.22.2 Example<span class="pull-right"><a class="anchor hidden-xs" href="#Example" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Example" aria-hidden="true">TOC</a></span></h4>
<p>Smooth Streaming content can be pushed in real time to a publishing
point on IIS with this muxer. Example:
</p><div class="example">
<pre class="example">ffmpeg -re <var><normal input/transcoding options></var> -movflags isml+frag_keyframe -f ismv http://server/publishingpoint.isml/Streams(Encoder1)
</pre></div>
<a name="mp3"></a>
<h3 class="section">4.23 mp3<span class="pull-right"><a class="anchor hidden-xs" href="#mp3" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-mp3" aria-hidden="true">TOC</a></span></h3>
<p>The MP3 muxer writes a raw MP3 stream with the following optional features:
</p><ul>
<li> An ID3v2 metadata header at the beginning (enabled by default). Versions 2.3 and
2.4 are supported, the <code>id3v2_version</code> private option controls which one is
used (3 or 4). Setting <code>id3v2_version</code> to 0 disables the ID3v2 header
completely.
<p>The muxer supports writing attached pictures (APIC frames) to the ID3v2 header.
The pictures are supplied to the muxer in form of a video stream with a single
packet. There can be any number of those streams, each will correspond to a
single APIC frame. The stream metadata tags <var>title</var> and <var>comment</var> map
to APIC <var>description</var> and <var>picture type</var> respectively. See
<a href="http://id3.org/id3v2.4.0-frames">http://id3.org/id3v2.4.0-frames</a> for allowed picture types.
</p>
<p>Note that the APIC frames must be written at the beginning, so the muxer will
buffer the audio frames until it gets all the pictures. It is therefore advised
to provide the pictures as soon as possible to avoid excessive buffering.
</p>
</li><li> A Xing/LAME frame right after the ID3v2 header (if present). It is enabled by
default, but will be written only if the output is seekable. The
<code>write_xing</code> private option can be used to disable it. The frame contains
various information that may be useful to the decoder, like the audio duration
or encoder delay.
</li><li> A legacy ID3v1 tag at the end of the file (disabled by default). It may be
enabled with the <code>write_id3v1</code> private option, but as its capabilities are
very limited, its usage is not recommended.
</li></ul>
<p>Examples:
</p>
<p>Write an mp3 with an ID3v2.3 header and an ID3v1 footer:
</p><div class="example">
<pre class="example">ffmpeg -i INPUT -id3v2_version 3 -write_id3v1 1 out.mp3
</pre></div>
<p>To attach a picture to an mp3 file select both the audio and the picture stream
with <code>map</code>:
</p><div class="example">
<pre class="example">ffmpeg -i input.mp3 -i cover.png -c copy -map 0 -map 1
-metadata:s:v title="Album cover" -metadata:s:v comment="Cover (Front)" out.mp3
</pre></div>
<p>Write a "clean" MP3 without any extra features:
</p><div class="example">
<pre class="example">ffmpeg -i input.wav -write_xing 0 -id3v2_version 0 out.mp3
</pre></div>
<a name="mpegts-1"></a>
<h3 class="section">4.24 mpegts<span class="pull-right"><a class="anchor hidden-xs" href="#mpegts-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-mpegts-1" aria-hidden="true">TOC</a></span></h3>
<p>MPEG transport stream muxer.
</p>
<p>This muxer implements ISO 13818-1 and part of ETSI EN 300 468.
</p>
<p>The recognized metadata settings in mpegts muxer are <code>service_provider</code>
and <code>service_name</code>. If they are not set the default for
<code>service_provider</code> is ‘<samp>FFmpeg</samp>’ and the default for
<code>service_name</code> is ‘<samp>Service01</samp>’.
</p>
<a name="Options-13"></a>
<h4 class="subsection">4.24.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-13" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-13" aria-hidden="true">TOC</a></span></h4>
<p>The muxer options are:
</p>
<dl compact="compact">
<dt><span><samp>mpegts_transport_stream_id <var>integer</var></samp></span></dt>
<dd><p>Set the ‘<samp>transport_stream_id</samp>’. This identifies a transponder in DVB.
Default is <code>0x0001</code>.
</p>
</dd>
<dt><span><samp>mpegts_original_network_id <var>integer</var></samp></span></dt>
<dd><p>Set the ‘<samp>original_network_id</samp>’. This is unique identifier of a
network in DVB. Its main use is in the unique identification of a service
through the path ‘<samp>Original_Network_ID, Transport_Stream_ID</samp>’. Default
is <code>0x0001</code>.
</p>
</dd>
<dt><span><samp>mpegts_service_id <var>integer</var></samp></span></dt>
<dd><p>Set the ‘<samp>service_id</samp>’, also known as program in DVB. Default is
<code>0x0001</code>.
</p>
</dd>
<dt><span><samp>mpegts_service_type <var>integer</var></samp></span></dt>
<dd><p>Set the program ‘<samp>service_type</samp>’. Default is <code>digital_tv</code>.
Accepts the following options:
</p><dl compact="compact">
<dt><span>‘<samp>hex_value</samp>’</span></dt>
<dd><p>Any hexadecimal value between <code>0x01</code> and <code>0xff</code> as defined in
ETSI 300 468.
</p></dd>
<dt><span>‘<samp>digital_tv</samp>’</span></dt>
<dd><p>Digital TV service.
</p></dd>
<dt><span>‘<samp>digital_radio</samp>’</span></dt>
<dd><p>Digital Radio service.
</p></dd>
<dt><span>‘<samp>teletext</samp>’</span></dt>
<dd><p>Teletext service.
</p></dd>
<dt><span>‘<samp>advanced_codec_digital_radio</samp>’</span></dt>
<dd><p>Advanced Codec Digital Radio service.
</p></dd>
<dt><span>‘<samp>mpeg2_digital_hdtv</samp>’</span></dt>
<dd><p>MPEG2 Digital HDTV service.
</p></dd>
<dt><span>‘<samp>advanced_codec_digital_sdtv</samp>’</span></dt>
<dd><p>Advanced Codec Digital SDTV service.
</p></dd>
<dt><span>‘<samp>advanced_codec_digital_hdtv</samp>’</span></dt>
<dd><p>Advanced Codec Digital HDTV service.
</p></dd>
</dl>
</dd>
<dt><span><samp>mpegts_pmt_start_pid <var>integer</var></samp></span></dt>
<dd><p>Set the first PID for PMTs. Default is <code>0x1000</code>, minimum is <code>0x0020</code>,
maximum is <code>0x1ffa</code>. This option has no effect in m2ts mode where the PMT
PID is fixed <code>0x0100</code>.
</p>
</dd>
<dt><span><samp>mpegts_start_pid <var>integer</var></samp></span></dt>
<dd><p>Set the first PID for elementary streams. Default is <code>0x0100</code>, minimum is
<code>0x0020</code>, maximum is <code>0x1ffa</code>. This option has no effect in m2ts mode
where the elementary stream PIDs are fixed.
</p>
</dd>
<dt><span><samp>mpegts_m2ts_mode <var>boolean</var></samp></span></dt>
<dd><p>Enable m2ts mode if set to <code>1</code>. Default value is <code>-1</code> which
disables m2ts mode.
</p>
</dd>
<dt><span><samp>muxrate <var>integer</var></samp></span></dt>
<dd><p>Set a constant muxrate. Default is VBR.
</p>
</dd>
<dt><span><samp>pes_payload_size <var>integer</var></samp></span></dt>
<dd><p>Set minimum PES packet payload in bytes. Default is <code>2930</code>.
</p>
</dd>
<dt><span><samp>mpegts_flags <var>flags</var></samp></span></dt>
<dd><p>Set mpegts flags. Accepts the following options:
</p><dl compact="compact">
<dt><span>‘<samp>resend_headers</samp>’</span></dt>
<dd><p>Reemit PAT/PMT before writing the next packet.
</p></dd>
<dt><span>‘<samp>latm</samp>’</span></dt>
<dd><p>Use LATM packetization for AAC.
</p></dd>
<dt><span>‘<samp>pat_pmt_at_frames</samp>’</span></dt>
<dd><p>Reemit PAT and PMT at each video frame.
</p></dd>
<dt><span>‘<samp>system_b</samp>’</span></dt>
<dd><p>Conform to System B (DVB) instead of System A (ATSC).
</p></dd>
<dt><span>‘<samp>initial_discontinuity</samp>’</span></dt>
<dd><p>Mark the initial packet of each stream as discontinuity.
</p></dd>
<dt><span>‘<samp>nit</samp>’</span></dt>
<dd><p>Emit NIT table.
</p></dd>
<dt><span>‘<samp>omit_rai</samp>’</span></dt>
<dd><p>Disable writing of random access indicator.
</p></dd>
</dl>
</dd>
<dt><span><samp>mpegts_copyts <var>boolean</var></samp></span></dt>
<dd><p>Preserve original timestamps, if value is set to <code>1</code>. Default value
is <code>-1</code>, which results in shifting timestamps so that they start from 0.
</p>
</dd>
<dt><span><samp>omit_video_pes_length <var>boolean</var></samp></span></dt>
<dd><p>Omit the PES packet length for video packets. Default is <code>1</code> (true).
</p>
</dd>
<dt><span><samp>pcr_period <var>integer</var></samp></span></dt>
<dd><p>Override the default PCR retransmission time in milliseconds. Default is
<code>-1</code> which means that the PCR interval will be determined automatically:
20 ms is used for CBR streams, the highest multiple of the frame duration which
is less than 100 ms is used for VBR streams.
</p>
</dd>
<dt><span><samp>pat_period <var>duration</var></samp></span></dt>
<dd><p>Maximum time in seconds between PAT/PMT tables. Default is <code>0.1</code>.
</p>
</dd>
<dt><span><samp>sdt_period <var>duration</var></samp></span></dt>
<dd><p>Maximum time in seconds between SDT tables. Default is <code>0.5</code>.
</p>
</dd>
<dt><span><samp>nit_period <var>duration</var></samp></span></dt>
<dd><p>Maximum time in seconds between NIT tables. Default is <code>0.5</code>.
</p>
</dd>
<dt><span><samp>tables_version <var>integer</var></samp></span></dt>
<dd><p>Set PAT, PMT, SDT and NIT version (default <code>0</code>, valid values are from 0 to 31, inclusively).
This option allows updating stream structure so that standard consumer may
detect the change. To do so, reopen output <code>AVFormatContext</code> (in case of API
usage) or restart <code>ffmpeg</code> instance, cyclically changing
<samp>tables_version</samp> value:
</p>
<div class="example">
<pre class="example">ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
...
ffmpeg -i source3.ts -codec copy -f mpegts -tables_version 31 udp://1.1.1.1:1111
ffmpeg -i source1.ts -codec copy -f mpegts -tables_version 0 udp://1.1.1.1:1111
ffmpeg -i source2.ts -codec copy -f mpegts -tables_version 1 udp://1.1.1.1:1111
...
</pre></div>
</dd>
</dl>
<a name="Example-1"></a>
<h4 class="subsection">4.24.2 Example<span class="pull-right"><a class="anchor hidden-xs" href="#Example-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Example-1" aria-hidden="true">TOC</a></span></h4>
<div class="example">
<pre class="example">ffmpeg -i file.mpg -c copy \
-mpegts_original_network_id 0x1122 \
-mpegts_transport_stream_id 0x3344 \
-mpegts_service_id 0x5566 \
-mpegts_pmt_start_pid 0x1500 \
-mpegts_start_pid 0x150 \
-metadata service_provider="Some provider" \
-metadata service_name="Some Channel" \
out.ts
</pre></div>
<a name="mxf_002c-mxf_005fd10_002c-mxf_005fopatom"></a>
<h3 class="section">4.25 mxf, mxf_d10, mxf_opatom<span class="pull-right"><a class="anchor hidden-xs" href="#mxf_002c-mxf_005fd10_002c-mxf_005fopatom" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-mxf_002c-mxf_005fd10_002c-mxf_005fopatom" aria-hidden="true">TOC</a></span></h3>
<p>MXF muxer.
</p>
<a name="Options-14"></a>
<h4 class="subsection">4.25.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-14" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-14" aria-hidden="true">TOC</a></span></h4>
<p>The muxer options are:
</p>
<dl compact="compact">
<dt><span><samp>store_user_comments <var>bool</var></samp></span></dt>
<dd><p>Set if user comments should be stored if available or never.
IRT D-10 does not allow user comments. The default is thus to write them for
mxf and mxf_opatom but not for mxf_d10
</p></dd>
</dl>
<a name="null"></a>
<h3 class="section">4.26 null<span class="pull-right"><a class="anchor hidden-xs" href="#null" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-null" aria-hidden="true">TOC</a></span></h3>
<p>Null muxer.
</p>
<p>This muxer does not generate any output file, it is mainly useful for
testing or benchmarking purposes.
</p>
<p>For example to benchmark decoding with <code>ffmpeg</code> you can use the
command:
</p><div class="example">
<pre class="example">ffmpeg -benchmark -i INPUT -f null out.null
</pre></div>
<p>Note that the above command does not read or write the <samp>out.null</samp>
file, but specifying the output file is required by the <code>ffmpeg</code>
syntax.
</p>
<p>Alternatively you can write the command as:
</p><div class="example">
<pre class="example">ffmpeg -benchmark -i INPUT -f null -
</pre></div>
<a name="nut"></a>
<h3 class="section">4.27 nut<span class="pull-right"><a class="anchor hidden-xs" href="#nut" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-nut" aria-hidden="true">TOC</a></span></h3>
<dl compact="compact">
<dt><span><samp>-syncpoints <var>flags</var></samp></span></dt>
<dd><p>Change the syncpoint usage in nut:
</p><dl compact="compact">
<dt><span><samp><var>default</var> use the normal low-overhead seeking aids.</samp></span></dt>
<dt><span><samp><var>none</var> do not use the syncpoints at all, reducing the overhead but making the stream non-seekable;</samp></span></dt>
<dd><p>Use of this option is not recommended, as the resulting files are very damage
sensitive and seeking is not possible. Also in general the overhead from
syncpoints is negligible. Note, -<code>write_index</code> 0 can be used to disable
all growing data tables, allowing to mux endless streams with limited memory
and without these disadvantages.
</p></dd>
<dt><span><samp><var>timestamped</var> extend the syncpoint with a wallclock field.</samp></span></dt>
</dl>
<p>The <var>none</var> and <var>timestamped</var> flags are experimental.
</p></dd>
<dt><span><samp>-write_index <var>bool</var></samp></span></dt>
<dd><p>Write index at the end, the default is to write an index.
</p></dd>
</dl>
<div class="example">
<pre class="example">ffmpeg -i INPUT -f_strict experimental -syncpoints none - | processor
</pre></div>
<a name="ogg"></a>
<h3 class="section">4.28 ogg<span class="pull-right"><a class="anchor hidden-xs" href="#ogg" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-ogg" aria-hidden="true">TOC</a></span></h3>
<p>Ogg container muxer.
</p>
<dl compact="compact">
<dt><span><samp>-page_duration <var>duration</var></samp></span></dt>
<dd><p>Preferred page duration, in microseconds. The muxer will attempt to create
pages that are approximately <var>duration</var> microseconds long. This allows the
user to compromise between seek granularity and container overhead. The default
is 1 second. A value of 0 will fill all segments, making pages as large as
possible. A value of 1 will effectively use 1 packet-per-page in most
situations, giving a small seek granularity at the cost of additional container
overhead.
</p></dd>
<dt><span><samp>-serial_offset <var>value</var></samp></span></dt>
<dd><p>Serial value from which to set the streams serial number.
Setting it to different and sufficiently large values ensures that the produced
ogg files can be safely chained.
</p>
</dd>
</dl>
<span id="raw-muxers"></span><a name="raw-muxers-1"></a>
<h3 class="section">4.29 raw muxers<span class="pull-right"><a class="anchor hidden-xs" href="#raw-muxers-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-raw-muxers-1" aria-hidden="true">TOC</a></span></h3>
<p>Raw muxers accept a single stream matching the designated codec. They do not store timestamps or metadata.
The recognized extension is the same as the muxer name unless indicated otherwise.
</p>
<a name="ac3"></a>
<h4 class="subsection">4.29.1 ac3<span class="pull-right"><a class="anchor hidden-xs" href="#ac3" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-ac3" aria-hidden="true">TOC</a></span></h4>
<p>Dolby Digital, also known as AC-3, audio.
</p>
<a name="adx"></a>
<h4 class="subsection">4.29.2 adx<span class="pull-right"><a class="anchor hidden-xs" href="#adx" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-adx" aria-hidden="true">TOC</a></span></h4>
<p>CRI Middleware ADX audio.
</p>
<p>This muxer will write out the total sample count near the start of the first packet
when the output is seekable and the count can be stored in 32 bits.
</p>
<a name="aptx"></a>
<h4 class="subsection">4.29.3 aptx<span class="pull-right"><a class="anchor hidden-xs" href="#aptx" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-aptx" aria-hidden="true">TOC</a></span></h4>
<p>aptX (Audio Processing Technology for Bluetooth) audio.
</p>
<a name="aptx_005fhd"></a>
<h4 class="subsection">4.29.4 aptx_hd<span class="pull-right"><a class="anchor hidden-xs" href="#aptx_005fhd" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-aptx_005fhd" aria-hidden="true">TOC</a></span></h4>
<p>aptX HD (Audio Processing Technology for Bluetooth) audio.
</p>
<p>Extensions: aptxhd
</p>
<a name="avs2"></a>
<h4 class="subsection">4.29.5 avs2<span class="pull-right"><a class="anchor hidden-xs" href="#avs2" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-avs2" aria-hidden="true">TOC</a></span></h4>
<p>AVS2-P2/IEEE1857.4 video.
</p>
<p>Extensions: avs, avs2
</p>
<a name="cavsvideo"></a>
<h4 class="subsection">4.29.6 cavsvideo<span class="pull-right"><a class="anchor hidden-xs" href="#cavsvideo" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-cavsvideo" aria-hidden="true">TOC</a></span></h4>
<p>Chinese AVS (Audio Video Standard) video.
</p>
<p>Extensions: cavs
</p>
<a name="codec2raw"></a>
<h4 class="subsection">4.29.7 codec2raw<span class="pull-right"><a class="anchor hidden-xs" href="#codec2raw" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-codec2raw" aria-hidden="true">TOC</a></span></h4>
<p>Codec 2 audio.
</p>
<p>No extension is registered so format name has to be supplied e.g. with the ffmpeg CLI tool <code>-f codec2raw</code>.
</p>
<a name="data"></a>
<h4 class="subsection">4.29.8 data<span class="pull-right"><a class="anchor hidden-xs" href="#data" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-data" aria-hidden="true">TOC</a></span></h4>
<p>Data muxer accepts a single stream with any codec of any type.
The input stream has to be selected using the <code>-map</code> option with the ffmpeg CLI tool.
</p>
<p>No extension is registered so format name has to be supplied e.g. with the ffmpeg CLI tool <code>-f data</code>.
</p>
<a name="dirac"></a>
<h4 class="subsection">4.29.9 dirac<span class="pull-right"><a class="anchor hidden-xs" href="#dirac" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-dirac" aria-hidden="true">TOC</a></span></h4>
<p>BBC Dirac video. The Dirac Pro codec is a subset and is standardized as SMPTE VC-2.
</p>
<p>Extensions: drc, vc2
</p>
<a name="dnxhd"></a>
<h4 class="subsection">4.29.10 dnxhd<span class="pull-right"><a class="anchor hidden-xs" href="#dnxhd" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-dnxhd" aria-hidden="true">TOC</a></span></h4>
<p>Avid DNxHD video. It is standardized as SMPTE VC-3. Accepts DNxHR streams.
</p>
<p>Extensions: dnxhd, dnxhr
</p>
<a name="dts"></a>
<h4 class="subsection">4.29.11 dts<span class="pull-right"><a class="anchor hidden-xs" href="#dts" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-dts" aria-hidden="true">TOC</a></span></h4>
<p>DTS Coherent Acoustics (DCA) audio.
</p>
<a name="eac3"></a>
<h4 class="subsection">4.29.12 eac3<span class="pull-right"><a class="anchor hidden-xs" href="#eac3" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-eac3" aria-hidden="true">TOC</a></span></h4>
<p>Dolby Digital Plus, also known as Enhanced AC-3, audio.
</p>
<a name="g722"></a>
<h4 class="subsection">4.29.13 g722<span class="pull-right"><a class="anchor hidden-xs" href="#g722" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-g722" aria-hidden="true">TOC</a></span></h4>
<p>ITU-T G.722 audio.
</p>
<a name="g723_005f1"></a>
<h4 class="subsection">4.29.14 g723_1<span class="pull-right"><a class="anchor hidden-xs" href="#g723_005f1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-g723_005f1" aria-hidden="true">TOC</a></span></h4>
<p>ITU-T G.723.1 audio.
</p>
<p>Extensions: tco, rco
</p>
<a name="g726"></a>
<h4 class="subsection">4.29.15 g726<span class="pull-right"><a class="anchor hidden-xs" href="#g726" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-g726" aria-hidden="true">TOC</a></span></h4>
<p>ITU-T G.726 big-endian ("left-justified") audio.
</p>
<p>No extension is registered so format name has to be supplied e.g. with the ffmpeg CLI tool <code>-f g726</code>.
</p>
<a name="g726le"></a>
<h4 class="subsection">4.29.16 g726le<span class="pull-right"><a class="anchor hidden-xs" href="#g726le" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-g726le" aria-hidden="true">TOC</a></span></h4>
<p>ITU-T G.726 little-endian ("right-justified") audio.
</p>
<p>No extension is registered so format name has to be supplied e.g. with the ffmpeg CLI tool <code>-f g726le</code>.
</p>
<a name="gsm"></a>
<h4 class="subsection">4.29.17 gsm<span class="pull-right"><a class="anchor hidden-xs" href="#gsm" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-gsm" aria-hidden="true">TOC</a></span></h4>
<p>Global System for Mobile Communications audio.
</p>
<a name="h261"></a>
<h4 class="subsection">4.29.18 h261<span class="pull-right"><a class="anchor hidden-xs" href="#h261" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-h261" aria-hidden="true">TOC</a></span></h4>
<p>ITU-T H.261 video.
</p>
<a name="h263"></a>
<h4 class="subsection">4.29.19 h263<span class="pull-right"><a class="anchor hidden-xs" href="#h263" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-h263" aria-hidden="true">TOC</a></span></h4>
<p>ITU-T H.263 / H.263-1996, H.263+ / H.263-1998 / H.263 version 2 video.
</p>
<a name="h264"></a>
<h4 class="subsection">4.29.20 h264<span class="pull-right"><a class="anchor hidden-xs" href="#h264" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-h264" aria-hidden="true">TOC</a></span></h4>
<p>ITU-T H.264 / MPEG-4 Part 10 AVC video. Bitstream shall be converted to Annex B syntax if it’s in length-prefixed mode.
</p>
<p>Extensions: h264, 264
</p>
<a name="hevc"></a>
<h4 class="subsection">4.29.21 hevc<span class="pull-right"><a class="anchor hidden-xs" href="#hevc" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-hevc" aria-hidden="true">TOC</a></span></h4>
<p>ITU-T H.265 / MPEG-H Part 2 HEVC video. Bitstream shall be converted to Annex B syntax if it’s in length-prefixed mode.
</p>
<p>Extensions: hevc, h265, 265
</p>
<a name="m4v"></a>
<h4 class="subsection">4.29.22 m4v<span class="pull-right"><a class="anchor hidden-xs" href="#m4v" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-m4v" aria-hidden="true">TOC</a></span></h4>
<p>MPEG-4 Part 2 video.
</p>
<a name="mjpeg"></a>
<h4 class="subsection">4.29.23 mjpeg<span class="pull-right"><a class="anchor hidden-xs" href="#mjpeg" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-mjpeg" aria-hidden="true">TOC</a></span></h4>
<p>Motion JPEG video.
</p>
<p>Extensions: mjpg, mjpeg
</p>
<a name="mlp"></a>
<h4 class="subsection">4.29.24 mlp<span class="pull-right"><a class="anchor hidden-xs" href="#mlp" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-mlp" aria-hidden="true">TOC</a></span></h4>
<p>Meridian Lossless Packing, also known as Packed PCM, audio.
</p>
<a name="mp2"></a>
<h4 class="subsection">4.29.25 mp2<span class="pull-right"><a class="anchor hidden-xs" href="#mp2" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-mp2" aria-hidden="true">TOC</a></span></h4>
<p>MPEG-1 Audio Layer II audio.
</p>
<p>Extensions: mp2, m2a, mpa
</p>
<a name="mpeg1video"></a>
<h4 class="subsection">4.29.26 mpeg1video<span class="pull-right"><a class="anchor hidden-xs" href="#mpeg1video" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-mpeg1video" aria-hidden="true">TOC</a></span></h4>
<p>MPEG-1 Part 2 video.
</p>
<p>Extensions: mpg, mpeg, m1v
</p>
<a name="mpeg2video"></a>
<h4 class="subsection">4.29.27 mpeg2video<span class="pull-right"><a class="anchor hidden-xs" href="#mpeg2video" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-mpeg2video" aria-hidden="true">TOC</a></span></h4>
<p>ITU-T H.262 / MPEG-2 Part 2 video.
</p>
<p>Extensions: m2v
</p>
<a name="obu"></a>
<h4 class="subsection">4.29.28 obu<span class="pull-right"><a class="anchor hidden-xs" href="#obu" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-obu" aria-hidden="true">TOC</a></span></h4>
<p>AV1 low overhead Open Bitstream Units muxer. Temporal delimiter OBUs will be inserted in all temporal units of the stream.
</p>
<a name="rawvideo-1"></a>
<h4 class="subsection">4.29.29 rawvideo<span class="pull-right"><a class="anchor hidden-xs" href="#rawvideo-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-rawvideo-1" aria-hidden="true">TOC</a></span></h4>
<p>Raw uncompressed video.
</p>
<p>Extensions: yuv, rgb
</p>
<a name="sbc"></a>
<h4 class="subsection">4.29.30 sbc<span class="pull-right"><a class="anchor hidden-xs" href="#sbc" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-sbc" aria-hidden="true">TOC</a></span></h4>
<p>Bluetooth SIG low-complexity subband codec audio.
</p>
<p>Extensions: sbc, msbc
</p>
<a name="truehd"></a>
<h4 class="subsection">4.29.31 truehd<span class="pull-right"><a class="anchor hidden-xs" href="#truehd" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-truehd" aria-hidden="true">TOC</a></span></h4>
<p>Dolby TrueHD audio.
</p>
<p>Extensions: thd
</p>
<a name="vc1"></a>
<h4 class="subsection">4.29.32 vc1<span class="pull-right"><a class="anchor hidden-xs" href="#vc1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-vc1" aria-hidden="true">TOC</a></span></h4>
<p>SMPTE 421M / VC-1 video.
</p>
<span id="segment"></span><a name="segment_002c-stream_005fsegment_002c-ssegment"></a>
<h3 class="section">4.30 segment, stream_segment, ssegment<span class="pull-right"><a class="anchor hidden-xs" href="#segment_002c-stream_005fsegment_002c-ssegment" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-segment_002c-stream_005fsegment_002c-ssegment" aria-hidden="true">TOC</a></span></h3>
<p>Basic stream segmenter.
</p>
<p>This muxer outputs streams to a number of separate files of nearly
fixed duration. Output filename pattern can be set in a fashion
similar to <a href="#image2">image2</a>, or by using a <code>strftime</code> template if
the <samp>strftime</samp> option is enabled.
</p>
<p><code>stream_segment</code> is a variant of the muxer used to write to
streaming output formats, i.e. which do not require global headers,
and is recommended for outputting e.g. to MPEG transport stream segments.
<code>ssegment</code> is a shorter alias for <code>stream_segment</code>.
</p>
<p>Every segment starts with a keyframe of the selected reference stream,
which is set through the <samp>reference_stream</samp> option.
</p>
<p>Note that if you want accurate splitting for a video file, you need to
make the input key frames correspond to the exact splitting times
expected by the segmenter, or the segment muxer will start the new
segment with the key frame found next after the specified start
time.
</p>
<p>The segment muxer works best with a single constant frame rate video.
</p>
<p>Optionally it can generate a list of the created segments, by setting
the option <var>segment_list</var>. The list type is specified by the
<var>segment_list_type</var> option. The entry filenames in the segment
list are set by default to the basename of the corresponding segment
files.
</p>
<p>See also the <a href="#hls">hls</a> muxer, which provides a more specific
implementation for HLS segmentation.
</p>
<a name="Options-15"></a>
<h4 class="subsection">4.30.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-15" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-15" aria-hidden="true">TOC</a></span></h4>
<p>The segment muxer supports the following options:
</p>
<dl compact="compact">
<dt><span><samp>increment_tc <var>1|0</var></samp></span></dt>
<dd><p>if set to <code>1</code>, increment timecode between each segment
If this is selected, the input need to have
a timecode in the first video stream. Default value is
<code>0</code>.
</p>
</dd>
<dt><span><samp>reference_stream <var>specifier</var></samp></span></dt>
<dd><p>Set the reference stream, as specified by the string <var>specifier</var>.
If <var>specifier</var> is set to <code>auto</code>, the reference is chosen
automatically. Otherwise it must be a stream specifier (see the “Stream
specifiers” chapter in the ffmpeg manual) which specifies the
reference stream. The default value is <code>auto</code>.
</p>
</dd>
<dt><span><samp>segment_format <var>format</var></samp></span></dt>
<dd><p>Override the inner container format, by default it is guessed by the filename
extension.
</p>
</dd>
<dt><span><samp>segment_format_options <var>options_list</var></samp></span></dt>
<dd><p>Set output format options using a :-separated list of key=value
parameters. Values containing the <code>:</code> special character must be
escaped.
</p>
</dd>
<dt><span><samp>segment_list <var>name</var></samp></span></dt>
<dd><p>Generate also a listfile named <var>name</var>. If not specified no
listfile is generated.
</p>
</dd>
<dt><span><samp>segment_list_flags <var>flags</var></samp></span></dt>
<dd><p>Set flags affecting the segment list generation.
</p>
<p>It currently supports the following flags:
</p><dl compact="compact">
<dt><span>‘<samp>cache</samp>’</span></dt>
<dd><p>Allow caching (only affects M3U8 list files).
</p>
</dd>
<dt><span>‘<samp>live</samp>’</span></dt>
<dd><p>Allow live-friendly file generation.
</p></dd>
</dl>
</dd>
<dt><span><samp>segment_list_size <var>size</var></samp></span></dt>
<dd><p>Update the list file so that it contains at most <var>size</var>
segments. If 0 the list file will contain all the segments. Default
value is 0.
</p>
</dd>
<dt><span><samp>segment_list_entry_prefix <var>prefix</var></samp></span></dt>
<dd><p>Prepend <var>prefix</var> to each entry. Useful to generate absolute paths.
By default no prefix is applied.
</p>
</dd>
<dt><span><samp>segment_list_type <var>type</var></samp></span></dt>
<dd><p>Select the listing format.
</p>
<p>The following values are recognized:
</p><dl compact="compact">
<dt><span>‘<samp>flat</samp>’</span></dt>
<dd><p>Generate a flat list for the created segments, one segment per line.
</p>
</dd>
<dt><span>‘<samp>csv, ext</samp>’</span></dt>
<dd><p>Generate a list for the created segments, one segment per line,
each line matching the format (comma-separated values):
</p><div class="example">
<pre class="example"><var>segment_filename</var>,<var>segment_start_time</var>,<var>segment_end_time</var>
</pre></div>
<p><var>segment_filename</var> is the name of the output file generated by the
muxer according to the provided pattern. CSV escaping (according to
RFC4180) is applied if required.
</p>
<p><var>segment_start_time</var> and <var>segment_end_time</var> specify
the segment start and end time expressed in seconds.
</p>
<p>A list file with the suffix <code>".csv"</code> or <code>".ext"</code> will
auto-select this format.
</p>
<p>‘<samp>ext</samp>’ is deprecated in favor or ‘<samp>csv</samp>’.
</p>
</dd>
<dt><span>‘<samp>ffconcat</samp>’</span></dt>
<dd><p>Generate an ffconcat file for the created segments. The resulting file
can be read using the FFmpeg <a href="#concat">concat</a> demuxer.
</p>
<p>A list file with the suffix <code>".ffcat"</code> or <code>".ffconcat"</code> will
auto-select this format.
</p>
</dd>
<dt><span>‘<samp>m3u8</samp>’</span></dt>
<dd><p>Generate an extended M3U8 file, version 3, compliant with
<a href="http://tools.ietf.org/id/draft-pantos-http-live-streaming">http://tools.ietf.org/id/draft-pantos-http-live-streaming</a>.
</p>
<p>A list file with the suffix <code>".m3u8"</code> will auto-select this format.
</p></dd>
</dl>
<p>If not specified the type is guessed from the list file name suffix.
</p>
</dd>
<dt><span><samp>segment_time <var>time</var></samp></span></dt>
<dd><p>Set segment duration to <var>time</var>, the value must be a duration
specification. Default value is "2". See also the
<samp>segment_times</samp> option.
</p>
<p>Note that splitting may not be accurate, unless you force the
reference stream key-frames at the given time. See the introductory
notice and the examples below.
</p>
</dd>
<dt><span><samp>segment_atclocktime <var>1|0</var></samp></span></dt>
<dd><p>If set to "1" split at regular clock time intervals starting from 00:00
o’clock. The <var>time</var> value specified in <samp>segment_time</samp> is
used for setting the length of the splitting interval.
</p>
<p>For example with <samp>segment_time</samp> set to "900" this makes it possible
to create files at 12:00 o’clock, 12:15, 12:30, etc.
</p>
<p>Default value is "0".
</p>
</dd>
<dt><span><samp>segment_clocktime_offset <var>duration</var></samp></span></dt>
<dd><p>Delay the segment splitting times with the specified duration when using
<samp>segment_atclocktime</samp>.
</p>
<p>For example with <samp>segment_time</samp> set to "900" and
<samp>segment_clocktime_offset</samp> set to "300" this makes it possible to
create files at 12:05, 12:20, 12:35, etc.
</p>
<p>Default value is "0".
</p>
</dd>
<dt><span><samp>segment_clocktime_wrap_duration <var>duration</var></samp></span></dt>
<dd><p>Force the segmenter to only start a new segment if a packet reaches the muxer
within the specified duration after the segmenting clock time. This way you
can make the segmenter more resilient to backward local time jumps, such as
leap seconds or transition to standard time from daylight savings time.
</p>
<p>Default is the maximum possible duration which means starting a new segment
regardless of the elapsed time since the last clock time.
</p>
</dd>
<dt><span><samp>segment_time_delta <var>delta</var></samp></span></dt>
<dd><p>Specify the accuracy time when selecting the start time for a
segment, expressed as a duration specification. Default value is "0".
</p>
<p>When delta is specified a key-frame will start a new segment if its
PTS satisfies the relation:
</p><div class="example">
<pre class="example">PTS >= start_time - time_delta
</pre></div>
<p>This option is useful when splitting video content, which is always
split at GOP boundaries, in case a key frame is found just before the
specified split time.
</p>
<p>In particular may be used in combination with the <samp>ffmpeg</samp> option
<var>force_key_frames</var>. The key frame times specified by
<var>force_key_frames</var> may not be set accurately because of rounding
issues, with the consequence that a key frame time may result set just
before the specified time. For constant frame rate videos a value of
1/(2*<var>frame_rate</var>) should address the worst case mismatch between
the specified time and the time set by <var>force_key_frames</var>.
</p>
</dd>
<dt><span><samp>segment_times <var>times</var></samp></span></dt>
<dd><p>Specify a list of split points. <var>times</var> contains a list of comma
separated duration specifications, in increasing order. See also
the <samp>segment_time</samp> option.
</p>
</dd>
<dt><span><samp>segment_frames <var>frames</var></samp></span></dt>
<dd><p>Specify a list of split video frame numbers. <var>frames</var> contains a
list of comma separated integer numbers, in increasing order.
</p>
<p>This option specifies to start a new segment whenever a reference
stream key frame is found and the sequential number (starting from 0)
of the frame is greater or equal to the next value in the list.
</p>
</dd>
<dt><span><samp>segment_wrap <var>limit</var></samp></span></dt>
<dd><p>Wrap around segment index once it reaches <var>limit</var>.
</p>
</dd>
<dt><span><samp>segment_start_number <var>number</var></samp></span></dt>
<dd><p>Set the sequence number of the first segment. Defaults to <code>0</code>.
</p>
</dd>
<dt><span><samp>strftime <var>1|0</var></samp></span></dt>
<dd><p>Use the <code>strftime</code> function to define the name of the new
segments to write. If this is selected, the output segment name must
contain a <code>strftime</code> function template. Default value is
<code>0</code>.
</p>
</dd>
<dt><span><samp>break_non_keyframes <var>1|0</var></samp></span></dt>
<dd><p>If enabled, allow segments to start on frames other than keyframes. This
improves behavior on some players when the time between keyframes is
inconsistent, but may make things worse on others, and can cause some oddities
during seeking. Defaults to <code>0</code>.
</p>
</dd>
<dt><span><samp>reset_timestamps <var>1|0</var></samp></span></dt>
<dd><p>Reset timestamps at the beginning of each segment, so that each segment
will start with near-zero timestamps. It is meant to ease the playback
of the generated segments. May not work with some combinations of
muxers/codecs. It is set to <code>0</code> by default.
</p>
</dd>
<dt><span><samp>initial_offset <var>offset</var></samp></span></dt>
<dd><p>Specify timestamp offset to apply to the output packet timestamps. The
argument must be a time duration specification, and defaults to 0.
</p>
</dd>
<dt><span><samp>write_empty_segments <var>1|0</var></samp></span></dt>
<dd><p>If enabled, write an empty segment if there are no packets during the period a
segment would usually span. Otherwise, the segment will be filled with the next
packet written. Defaults to <code>0</code>.
</p></dd>
</dl>
<p>Make sure to require a closed GOP when encoding and to set the GOP
size to fit your segment time constraint.
</p>
<a name="Examples-10"></a>
<h4 class="subsection">4.30.2 Examples<span class="pull-right"><a class="anchor hidden-xs" href="#Examples-10" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Examples-10" aria-hidden="true">TOC</a></span></h4>
<ul>
<li> Remux the content of file <samp>in.mkv</samp> to a list of segments
<samp>out-000.nut</samp>, <samp>out-001.nut</samp>, etc., and write the list of
generated segments to <samp>out.list</samp>:
<div class="example">
<pre class="example">ffmpeg -i in.mkv -codec hevc -flags +cgop -g 60 -map 0 -f segment -segment_list out.list out%03d.nut
</pre></div>
</li><li> Segment input and set output format options for the output segments:
<div class="example">
<pre class="example">ffmpeg -i in.mkv -f segment -segment_time 10 -segment_format_options movflags=+faststart out%03d.mp4
</pre></div>
</li><li> Segment the input file according to the split points specified by the
<var>segment_times</var> option:
<div class="example">
<pre class="example">ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.csv -segment_times 1,2,3,5,8,13,21 out%03d.nut
</pre></div>
</li><li> Use the <code>ffmpeg</code> <samp>force_key_frames</samp>
option to force key frames in the input at the specified location, together
with the segment option <samp>segment_time_delta</samp> to account for
possible roundings operated when setting key frame times.
<div class="example">
<pre class="example">ffmpeg -i in.mkv -force_key_frames 1,2,3,5,8,13,21 -codec:v mpeg4 -codec:a pcm_s16le -map 0 \
-f segment -segment_list out.csv -segment_times 1,2,3,5,8,13,21 -segment_time_delta 0.05 out%03d.nut
</pre></div>
<p>In order to force key frames on the input file, transcoding is
required.
</p>
</li><li> Segment the input file by splitting the input file according to the
frame numbers sequence specified with the <samp>segment_frames</samp> option:
<div class="example">
<pre class="example">ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.csv -segment_frames 100,200,300,500,800 out%03d.nut
</pre></div>
</li><li> Convert the <samp>in.mkv</samp> to TS segments using the <code>libx264</code>
and <code>aac</code> encoders:
<div class="example">
<pre class="example">ffmpeg -i in.mkv -map 0 -codec:v libx264 -codec:a aac -f ssegment -segment_list out.list out%03d.ts
</pre></div>
</li><li> Segment the input file, and create an M3U8 live playlist (can be used
as live HLS source):
<div class="example">
<pre class="example">ffmpeg -re -i in.mkv -codec copy -map 0 -f segment -segment_list playlist.m3u8 \
-segment_list_flags +live -segment_time 10 out%03d.mkv
</pre></div>
</li></ul>
<a name="smoothstreaming"></a>
<h3 class="section">4.31 smoothstreaming<span class="pull-right"><a class="anchor hidden-xs" href="#smoothstreaming" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-smoothstreaming" aria-hidden="true">TOC</a></span></h3>
<p>Smooth Streaming muxer generates a set of files (Manifest, chunks) suitable for serving with conventional web server.
</p>
<dl compact="compact">
<dt><span><samp>window_size</samp></span></dt>
<dd><p>Specify the number of fragments kept in the manifest. Default 0 (keep all).
</p>
</dd>
<dt><span><samp>extra_window_size</samp></span></dt>
<dd><p>Specify the number of fragments kept outside of the manifest before removing from disk. Default 5.
</p>
</dd>
<dt><span><samp>lookahead_count</samp></span></dt>
<dd><p>Specify the number of lookahead fragments. Default 2.
</p>
</dd>
<dt><span><samp>min_frag_duration</samp></span></dt>
<dd><p>Specify the minimum fragment duration (in microseconds). Default 5000000.
</p>
</dd>
<dt><span><samp>remove_at_exit</samp></span></dt>
<dd><p>Specify whether to remove all fragments when finished. Default 0 (do not remove).
</p>
</dd>
</dl>
<span id="streamhash"></span><a name="streamhash-1"></a>
<h3 class="section">4.32 streamhash<span class="pull-right"><a class="anchor hidden-xs" href="#streamhash-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-streamhash-1" aria-hidden="true">TOC</a></span></h3>
<p>Per stream hash testing format.
</p>
<p>This muxer computes and prints a cryptographic hash of all the input frames,
on a per-stream basis. This can be used for equality checks without having
to do a complete binary comparison.
</p>
<p>By default audio frames are converted to signed 16-bit raw audio and
video frames to raw video before computing the hash, but the output
of explicit conversions to other codecs can also be used. Timestamps
are ignored. It uses the SHA-256 cryptographic hash function by default,
but supports several other algorithms.
</p>
<p>The output of the muxer consists of one line per stream of the form:
<var>streamindex</var>,<var>streamtype</var>,<var>algo</var>=<var>hash</var>, where
<var>streamindex</var> is the index of the mapped stream, <var>streamtype</var> is a
single character indicating the type of stream, <var>algo</var> is a short string
representing the hash function used, and <var>hash</var> is a hexadecimal number
representing the computed hash.
</p>
<dl compact="compact">
<dt><span><samp>hash <var>algorithm</var></samp></span></dt>
<dd><p>Use the cryptographic hash function specified by the string <var>algorithm</var>.
Supported values include <code>MD5</code>, <code>murmur3</code>, <code>RIPEMD128</code>,
<code>RIPEMD160</code>, <code>RIPEMD256</code>, <code>RIPEMD320</code>, <code>SHA160</code>,
<code>SHA224</code>, <code>SHA256</code> (default), <code>SHA512/224</code>, <code>SHA512/256</code>,
<code>SHA384</code>, <code>SHA512</code>, <code>CRC32</code> and <code>adler32</code>.
</p>
</dd>
</dl>
<a name="Examples-11"></a>
<h4 class="subsection">4.32.1 Examples<span class="pull-right"><a class="anchor hidden-xs" href="#Examples-11" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Examples-11" aria-hidden="true">TOC</a></span></h4>
<p>To compute the SHA-256 hash of the input converted to raw audio and
video, and store it in the file <samp>out.sha256</samp>:
</p><div class="example">
<pre class="example">ffmpeg -i INPUT -f streamhash out.sha256
</pre></div>
<p>To print an MD5 hash to stdout use the command:
</p><div class="example">
<pre class="example">ffmpeg -i INPUT -f streamhash -hash md5 -
</pre></div>
<p>See also the <a href="#hash">hash</a> and <a href="#framehash">framehash</a> muxers.
</p>
<span id="tee"></span><a name="tee-1"></a>
<h3 class="section">4.33 tee<span class="pull-right"><a class="anchor hidden-xs" href="#tee-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-tee-1" aria-hidden="true">TOC</a></span></h3>
<p>The tee muxer can be used to write the same data to several outputs, such as files or streams.
It can be used, for example, to stream a video over a network and save it to disk at the same time.
</p>
<p>It is different from specifying several outputs to the <code>ffmpeg</code>
command-line tool. With the tee muxer, the audio and video data will be encoded only once.
With conventional multiple outputs, multiple encoding operations in parallel are initiated,
which can be a very expensive process. The tee muxer is not useful when using the libavformat API
directly because it is then possible to feed the same packets to several muxers directly.
</p>
<p>Since the tee muxer does not represent any particular output format, ffmpeg cannot auto-select
output streams. So all streams intended for output must be specified using <code>-map</code>. See
the examples below.
</p>
<p>Some encoders may need different options depending on the output format;
the auto-detection of this can not work with the tee muxer, so they need to be explicitly specified.
The main example is the <samp>global_header</samp> flag.
</p>
<p>The slave outputs are specified in the file name given to the muxer,
separated by ’|’. If any of the slave name contains the ’|’ separator,
leading or trailing spaces or any special character, those must be
escaped (see <a data-manual="ffmpeg-utils" href="ffmpeg-utils.html#quoting_005fand_005fescaping">(ffmpeg-utils)the "Quoting and escaping"
section in the ffmpeg-utils(1) manual</a>).
</p>
<a name="Options-16"></a>
<h4 class="subsection">4.33.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-16" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-16" aria-hidden="true">TOC</a></span></h4>
<dl compact="compact">
<dt><span><samp>use_fifo <var>bool</var></samp></span></dt>
<dd><p>If set to 1, slave outputs will be processed in separate threads using the <a href="#fifo">fifo</a>
muxer. This allows to compensate for different speed/latency/reliability of
outputs and setup transparent recovery. By default this feature is turned off.
</p>
</dd>
<dt><span><samp>fifo_options</samp></span></dt>
<dd><p>Options to pass to fifo pseudo-muxer instances. See <a href="#fifo">fifo</a>.
</p>
</dd>
</dl>
<p>Muxer options can be specified for each slave by prepending them as a list of
<var>key</var>=<var>value</var> pairs separated by ’:’, between square brackets. If
the options values contain a special character or the ’:’ separator, they
must be escaped; note that this is a second level escaping.
</p>
<p>The following special options are also recognized:
</p><dl compact="compact">
<dt><span><samp>f</samp></span></dt>
<dd><p>Specify the format name. Required if it cannot be guessed from the
output URL.
</p>
</dd>
<dt><span><samp>bsfs[/<var>spec</var>]</samp></span></dt>
<dd><p>Specify a list of bitstream filters to apply to the specified
output.
</p>
<p>It is possible to specify to which streams a given bitstream filter
applies, by appending a stream specifier to the option separated by
<code>/</code>. <var>spec</var> must be a stream specifier (see <a href="#Format-stream-specifiers">Format stream specifiers</a>).
</p>
<p>If the stream specifier is not specified, the bitstream filters will be
applied to all streams in the output. This will cause that output operation
to fail if the output contains streams to which the bitstream filter cannot
be applied e.g. <code>h264_mp4toannexb</code> being applied to an output containing an audio stream.
</p>
<p>Options for a bitstream filter must be specified in the form of <code>opt=value</code>.
</p>
<p>Several bitstream filters can be specified, separated by ",".
</p>
</dd>
<dt><span><samp>use_fifo <var>bool</var></samp></span></dt>
<dd><p>This allows to override tee muxer use_fifo option for individual slave muxer.
</p>
</dd>
<dt><span><samp>fifo_options</samp></span></dt>
<dd><p>This allows to override tee muxer fifo_options for individual slave muxer.
See <a href="#fifo">fifo</a>.
</p>
</dd>
<dt><span><samp>select</samp></span></dt>
<dd><p>Select the streams that should be mapped to the slave output,
specified by a stream specifier. If not specified, this defaults to
all the mapped streams. This will cause that output operation to fail
if the output format does not accept all mapped streams.
</p>
<p>You may use multiple stream specifiers separated by commas (<code>,</code>) e.g.: <code>a:0,v</code>
</p>
</dd>
<dt><span><samp>onfail</samp></span></dt>
<dd><p>Specify behaviour on output failure. This can be set to either <code>abort</code> (which is
default) or <code>ignore</code>. <code>abort</code> will cause whole process to fail in case of failure
on this slave output. <code>ignore</code> will ignore failure on this output, so other outputs
will continue without being affected.
</p></dd>
</dl>
<a name="Examples-12"></a>
<h4 class="subsection">4.33.2 Examples<span class="pull-right"><a class="anchor hidden-xs" href="#Examples-12" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Examples-12" aria-hidden="true">TOC</a></span></h4>
<ul>
<li> Encode something and both archive it in a WebM file and stream it
as MPEG-TS over UDP:
<div class="example">
<pre class="example">ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
"archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
</pre></div>
</li><li> As above, but continue streaming even if output to local file fails
(for example local drive fills up):
<div class="example">
<pre class="example">ffmpeg -i ... -c:v libx264 -c:a mp2 -f tee -map 0:v -map 0:a
"[onfail=ignore]archive-20121107.mkv|[f=mpegts]udp://10.0.1.255:1234/"
</pre></div>
</li><li> Use <code>ffmpeg</code> to encode the input, and send the output
to three different destinations. The <code>dump_extra</code> bitstream
filter is used to add extradata information to all the output video
keyframes packets, as requested by the MPEG-TS format. The select
option is applied to <samp>out.aac</samp> in order to make it contain only
audio packets.
<div class="example">
<pre class="example">ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
-f tee "[bsfs/v=dump_extra=freq=keyframe]out.ts|[movflags=+faststart]out.mp4|[select=a]out.aac"
</pre></div>
</li><li> As above, but select only stream <code>a:1</code> for the audio output. Note
that a second level escaping must be performed, as ":" is a special
character used to separate options.
<div class="example">
<pre class="example">ffmpeg -i ... -map 0 -flags +global_header -c:v libx264 -c:a aac
-f tee "[bsfs/v=dump_extra=freq=keyframe]out.ts|[movflags=+faststart]out.mp4|[select=\'a:1\']out.aac"
</pre></div>
</li></ul>
<a name="webm_005fchunk"></a>
<h3 class="section">4.34 webm_chunk<span class="pull-right"><a class="anchor hidden-xs" href="#webm_005fchunk" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-webm_005fchunk" aria-hidden="true">TOC</a></span></h3>
<p>WebM Live Chunk Muxer.
</p>
<p>This muxer writes out WebM headers and chunks as separate files which can be
consumed by clients that support WebM Live streams via DASH.
</p>
<a name="Options-17"></a>
<h4 class="subsection">4.34.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-17" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-17" aria-hidden="true">TOC</a></span></h4>
<p>This muxer supports the following options:
</p>
<dl compact="compact">
<dt><span><samp>chunk_start_index</samp></span></dt>
<dd><p>Index of the first chunk (defaults to 0).
</p>
</dd>
<dt><span><samp>header</samp></span></dt>
<dd><p>Filename of the header where the initialization data will be written.
</p>
</dd>
<dt><span><samp>audio_chunk_duration</samp></span></dt>
<dd><p>Duration of each audio chunk in milliseconds (defaults to 5000).
</p></dd>
</dl>
<a name="Example-2"></a>
<h4 class="subsection">4.34.2 Example<span class="pull-right"><a class="anchor hidden-xs" href="#Example-2" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Example-2" aria-hidden="true">TOC</a></span></h4>
<div class="example">
<pre class="example">ffmpeg -f v4l2 -i /dev/video0 \
-f alsa -i hw:0 \
-map 0:0 \
-c:v libvpx-vp9 \
-s 640x360 -keyint_min 30 -g 30 \
-f webm_chunk \
-header webm_live_video_360.hdr \
-chunk_start_index 1 \
webm_live_video_360_%d.chk \
-map 1:0 \
-c:a libvorbis \
-b:a 128k \
-f webm_chunk \
-header webm_live_audio_128.hdr \
-chunk_start_index 1 \
-audio_chunk_duration 1000 \
webm_live_audio_128_%d.chk
</pre></div>
<a name="webm_005fdash_005fmanifest"></a>
<h3 class="section">4.35 webm_dash_manifest<span class="pull-right"><a class="anchor hidden-xs" href="#webm_005fdash_005fmanifest" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-webm_005fdash_005fmanifest" aria-hidden="true">TOC</a></span></h3>
<p>WebM DASH Manifest muxer.
</p>
<p>This muxer implements the WebM DASH Manifest specification to generate the DASH
manifest XML. It also supports manifest generation for DASH live streams.
</p>
<p>For more information see:
</p>
<ul>
<li> WebM DASH Specification: <a href="https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification">https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification</a>
</li><li> ISO DASH Specification: <a href="http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip">http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip</a>
</li></ul>
<a name="Options-18"></a>
<h4 class="subsection">4.35.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-18" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-18" aria-hidden="true">TOC</a></span></h4>
<p>This muxer supports the following options:
</p>
<dl compact="compact">
<dt><span><samp>adaptation_sets</samp></span></dt>
<dd><p>This option has the following syntax: "id=x,streams=a,b,c id=y,streams=d,e" where x and y are the
unique identifiers of the adaptation sets and a,b,c,d and e are the indices of the corresponding
audio and video streams. Any number of adaptation sets can be added using this option.
</p>
</dd>
<dt><span><samp>live</samp></span></dt>
<dd><p>Set this to 1 to create a live stream DASH Manifest. Default: 0.
</p>
</dd>
<dt><span><samp>chunk_start_index</samp></span></dt>
<dd><p>Start index of the first chunk. This will go in the ‘<samp>startNumber</samp>’ attribute
of the ‘<samp>SegmentTemplate</samp>’ element in the manifest. Default: 0.
</p>
</dd>
<dt><span><samp>chunk_duration_ms</samp></span></dt>
<dd><p>Duration of each chunk in milliseconds. This will go in the ‘<samp>duration</samp>’
attribute of the ‘<samp>SegmentTemplate</samp>’ element in the manifest. Default: 1000.
</p>
</dd>
<dt><span><samp>utc_timing_url</samp></span></dt>
<dd><p>URL of the page that will return the UTC timestamp in ISO format. This will go
in the ‘<samp>value</samp>’ attribute of the ‘<samp>UTCTiming</samp>’ element in the manifest.
Default: None.
</p>
</dd>
<dt><span><samp>time_shift_buffer_depth</samp></span></dt>
<dd><p>Smallest time (in seconds) shifting buffer for which any Representation is
guaranteed to be available. This will go in the ‘<samp>timeShiftBufferDepth</samp>’
attribute of the ‘<samp>MPD</samp>’ element. Default: 60.
</p>
</dd>
<dt><span><samp>minimum_update_period</samp></span></dt>
<dd><p>Minimum update period (in seconds) of the manifest. This will go in the
‘<samp>minimumUpdatePeriod</samp>’ attribute of the ‘<samp>MPD</samp>’ element. Default: 0.
</p>
</dd>
</dl>
<a name="Example-3"></a>
<h4 class="subsection">4.35.2 Example<span class="pull-right"><a class="anchor hidden-xs" href="#Example-3" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Example-3" aria-hidden="true">TOC</a></span></h4>
<div class="example">
<pre class="example">ffmpeg -f webm_dash_manifest -i video1.webm \
-f webm_dash_manifest -i video2.webm \
-f webm_dash_manifest -i audio1.webm \
-f webm_dash_manifest -i audio2.webm \
-map 0 -map 1 -map 2 -map 3 \
-c copy \
-f webm_dash_manifest \
-adaptation_sets "id=0,streams=0,1 id=1,streams=2,3" \
manifest.xml
</pre></div>
<a name="Metadata-1"></a>
<h2 class="chapter">5 Metadata<span class="pull-right"><a class="anchor hidden-xs" href="#Metadata-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Metadata-1" aria-hidden="true">TOC</a></span></h2>
<p>FFmpeg is able to dump metadata from media files into a simple UTF-8-encoded
INI-like text file and then load it back using the metadata muxer/demuxer.
</p>
<p>The file format is as follows:
</p><ol>
<li> A file consists of a header and a number of metadata tags divided into sections,
each on its own line.
</li><li> The header is a ‘<samp>;FFMETADATA</samp>’ string, followed by a version number (now 1).
</li><li> Metadata tags are of the form ‘<samp>key=value</samp>’
</li><li> Immediately after header follows global metadata
</li><li> After global metadata there may be sections with per-stream/per-chapter
metadata.
</li><li> A section starts with the section name in uppercase (i.e. STREAM or CHAPTER) in
brackets (‘<samp>[</samp>’, ‘<samp>]</samp>’) and ends with next section or end of file.
</li><li> At the beginning of a chapter section there may be an optional timebase to be
used for start/end values. It must be in form
‘<samp>TIMEBASE=<var>num</var>/<var>den</var></samp>’, where <var>num</var> and <var>den</var> are
integers. If the timebase is missing then start/end times are assumed to
be in nanoseconds.
<p>Next a chapter section must contain chapter start and end times in form
‘<samp>START=<var>num</var></samp>’, ‘<samp>END=<var>num</var></samp>’, where <var>num</var> is a positive
integer.
</p>
</li><li> Empty lines and lines starting with ‘<samp>;</samp>’ or ‘<samp>#</samp>’ are ignored.
</li><li> Metadata keys or values containing special characters (‘<samp>=</samp>’, ‘<samp>;</samp>’,
‘<samp>#</samp>’, ‘<samp>\</samp>’ and a newline) must be escaped with a backslash ‘<samp>\</samp>’.
</li><li> Note that whitespace in metadata (e.g. ‘<samp>foo = bar</samp>’) is considered to be
a part of the tag (in the example above key is ‘<samp>foo </samp>’, value is
‘<samp> bar</samp>’).
</li></ol>
<p>A ffmetadata file might look like this:
</p><div class="example">
<pre class="example">;FFMETADATA1
title=bike\\shed
;this is a comment
artist=FFmpeg troll team
[CHAPTER]
TIMEBASE=1/1000
START=0
#chapter ends at 0:01:00
END=60000
title=chapter \#1
[STREAM]
title=multi\
line
</pre></div>
<p>By using the ffmetadata muxer and demuxer it is possible to extract
metadata from an input file to an ffmetadata file, and then transcode
the file into an output file with the edited ffmetadata file.
</p>
<p>Extracting an ffmetadata file with <samp>ffmpeg</samp> goes as follows:
</p><div class="example">
<pre class="example">ffmpeg -i INPUT -f ffmetadata FFMETADATAFILE
</pre></div>
<p>Reinserting edited metadata information from the FFMETADATAFILE file can
be done as:
</p><div class="example">
<pre class="example">ffmpeg -i INPUT -i FFMETADATAFILE -map_metadata 1 -codec copy OUTPUT
</pre></div>
<a name="See-Also"></a>
<h2 class="chapter">6 See Also<span class="pull-right"><a class="anchor hidden-xs" href="#See-Also" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-See-Also" aria-hidden="true">TOC</a></span></h2>
<p><a href="ffmpeg.html">ffmpeg</a>, <a href="ffplay.html">ffplay</a>, <a href="ffprobe.html">ffprobe</a>,
<a href="libavformat.html">libavformat</a>
</p>
<a name="Authors"></a>
<h2 class="chapter">7 Authors<span class="pull-right"><a class="anchor hidden-xs" href="#Authors" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Authors" aria-hidden="true">TOC</a></span></h2>
<p>The FFmpeg developers.
</p>
<p>For details about the authorship, see the Git history of the project
(git://source.ffmpeg.org/ffmpeg), e.g. by typing the command
<code>git log</code> in the FFmpeg source directory, or browsing the
online repository at <a href="http://source.ffmpeg.org">http://source.ffmpeg.org</a>.
</p>
<p>Maintainers for the specific components are listed in the file
<samp>MAINTAINERS</samp> in the source code tree.
</p>
<p style="font-size: small;">
This document was generated using <a href="https://www.gnu.org/software/texinfo/"><em>makeinfo</em></a>.
</p>
</div>
</body>
</html>
|