This document describes the bitstream filters provided by the +libavcodec library. +
+A bitstream filter operates on the encoded stream data, and performs +bitstream level modifications without performing decoding. +
+ + +When you configure your FFmpeg build, all the supported bitstream
+filters are enabled by default. You can list all available ones using
+the configure option --list-bsfs.
+
You can disable all the bitstream filters using the configure option
+--disable-bsfs, and selectively enable any bitstream filter using
+the option --enable-bsf=BSF, or you can disable a particular
+bitstream filter using the option --disable-bsf=BSF.
+
The option -bsfs of the ff* tools will display the list of
+all the supported bitstream filters included in your build.
+
The ff* tools have a -bsf option applied per stream, taking a +comma-separated list of filters, whose parameters follow the filter +name after a ’=’. +
+ffmpeg -i INPUT -c:v copy -bsf:v filter1[=opt1=str1:opt2=str2][,filter2] OUTPUT +
Below is a description of the currently available bitstream filters, +with their parameters, if any. +
+ +Convert MPEG-2/4 AAC ADTS to an MPEG-4 Audio Specific Configuration +bitstream. +
+This filter creates an MPEG-4 AudioSpecificConfig from an MPEG-2/4 +ADTS header and removes the ADTS header. +
+This filter is required for example when copying an AAC stream from a +raw ADTS AAC or an MPEG-TS container to MP4A-LATM, to an FLV file, or +to MOV/MP4 files and related formats such as 3GP or M4A. Please note +that it is auto-inserted for MP4A-LATM and MOV/MP4 and related formats. +
+ +Modify metadata embedded in an AV1 stream. +
+Insert or remove temporal delimiter OBUs in all temporal units of the +stream. +
+Insert a TD at the beginning of every TU which does not already have one. +
Remove the TD from the beginning of every TU which has one. +
Set the color description fields in the stream (see AV1 section 6.4.2). +
+Set the color range in the stream (see AV1 section 6.4.2; note that +this cannot be set for streams using BT.709 primaries, sRGB transfer +characteristic and identity (RGB) matrix coefficients). +
Limited range. +
Full range. +
Set the chroma sample location in the stream (see AV1 section 6.4.2). +This can only be set for 4:2:0 streams. +
+Left position (matching the default in MPEG-2 and H.264). +
Top-left position. +
Set the tick rate (time_scale / num_units_in_display_tick) in +the timing info in the sequence header. +
Set the number of ticks in each picture, to indicate that the stream +has a fixed framerate. Ignored if tick_rate is not also set. +
+Deletes Padding OBUs. +
+Remove zero padding at the end of a packet. +
+ +Extract the core from a DCA/DTS stream, dropping extensions such as +DTS-HD. +
+ +Add extradata to the beginning of the filtered packets except when +said packets already exactly begin with the extradata that is intended +to be added. +
+The additional argument specifies which packets should be filtered. +It accepts the values: +
add extradata to all key packets +
+add extradata to all packets +
If not specified it is assumed ‘k’. +
+For example the following ffmpeg command forces a global
+header (thus disabling individual packet headers) in the H.264 packets
+generated by the libx264 encoder, but corrects them by adding
+the header stored in extradata to the key packets:
+
ffmpeg -i INPUT -map 0 -flags:v +global_header -c:v libx264 -bsf:v dump_extra out.ts +
Blocks in DV which are marked as damaged are replaced by blocks of the specified color. +
+The color to replace damaged blocks by +
A 16 bit mask which specifies which of the 16 possible error status values are +to be replaced by colored blocks. 0xFFFE is the default which replaces all non 0 +error status values. +
No error, no concealment +
Error, No concealment +
Reserved +
Error or concealment +
Not reserved +
The specific error status code +
see page 44-46 or section 5.5 of +http://web.archive.org/web/20060927044735/http://www.smpte.org/smpte_store/standards/pdf/s314m.pdf +
+Extract the core from a E-AC-3 stream, dropping extra channels. +
+ +Extract the in-band extradata. +
+Certain codecs allow the long-term headers (e.g. MPEG-2 sequence headers, +or H.264/HEVC (VPS/)SPS/PPS) to be transmitted either "in-band" (i.e. as a part +of the bitstream containing the coded frames) or "out of band" (e.g. on the +container level). This latter form is called "extradata" in FFmpeg terminology. +
+This bitstream filter detects the in-band headers and makes them available as +extradata. +
+When this option is enabled, the long-term headers are removed from the +bitstream after extraction. +
Remove units with types in or not in a given set from the stream. +
+List of unit types or ranges of unit types to pass through while removing +all others. This is specified as a ’|’-separated list of unit type values +or ranges of values with ’-’. +
+Identical to pass_types, except the units in the given set +removed and all others passed through. +
Extradata is unchanged by this transformation, but note that if the stream +contains inline parameter sets then the output may be unusable if they are +removed. +
+For example, to remove all non-VCL NAL units from an H.264 stream: +
ffmpeg -i INPUT -c:v copy -bsf:v 'filter_units=pass_types=1-5' OUTPUT +
To remove all AUDs, SEI and filler from an H.265 stream: +
ffmpeg -i INPUT -c:v copy -bsf:v 'filter_units=remove_types=35|38-40' OUTPUT +
Extract Rgb or Alpha part of an HAPQA file, without recompression, in order to create an HAPQ or an HAPAlphaOnly file. +
+Specifies the texture to keep. +
+Convert HAPQA to HAPQ +
ffmpeg -i hapqa_inputfile.mov -c copy -bsf:v hapqa_extract=texture=color -tag:v HapY -metadata:s:v:0 encoder="HAPQ" hapq_file.mov +
Convert HAPQA to HAPAlphaOnly +
ffmpeg -i hapqa_inputfile.mov -c copy -bsf:v hapqa_extract=texture=alpha -tag:v HapA -metadata:s:v:0 encoder="HAPAlpha Only" hapalphaonly_file.mov +
Modify metadata embedded in an H.264 stream. +
+Insert or remove AUD NAL units in all access units of the stream. +
+Default is pass. +
+Set the sample aspect ratio of the stream in the VUI parameters. +See H.264 table E-1. +
+Set whether the stream is suitable for display using overscan +or not (see H.264 section E.2.1). +
+Set the video format in the stream (see H.264 section E.2.1 and +table E-2). +
+Set the colour description in the stream (see H.264 section E.2.1 +and tables E-3, E-4 and E-5). +
+Set the chroma sample location in the stream (see H.264 section +E.2.1 and figure E-1). +
+Set the tick rate (time_scale / num_units_in_tick) in the VUI +parameters. This is the smallest time unit representable in the +stream, and in many cases represents the field rate of the stream +(double the frame rate). +
Set whether the stream has fixed framerate - typically this indicates +that the framerate is exactly half the tick rate, but the exact +meaning is dependent on interlacing and the picture structure (see +H.264 section E.2.1 and table E-6). +
Zero constraint_set4_flag and constraint_set5_flag in the SPS. These +bits were reserved in a previous version of the H.264 spec, and thus +some hardware decoders require these to be zero. The result of zeroing +this is still a valid bitstream. +
+Set the frame cropping offsets in the SPS. These values will replace +the current ones if the stream is already cropped. +
+These fields are set in pixels. Note that some sizes may not be +representable if the chroma is subsampled or the stream is interlaced +(see H.264 section 7.4.2.1.1). +
+Insert a string as SEI unregistered user data. The argument must +be of the form UUID+string, where the UUID is as hex digits +possibly separated by hyphens, and the string can be anything. +
+For example, ‘086f3693-b7b3-4f2c-9653-21492feee5b8+hello’ will +insert the string “hello” associated with the given UUID. +
+Deletes both filler NAL units and filler SEI messages. +
+Insert, extract or remove Display orientation SEI messages. +See H.264 section D.1.27 and D.2.27 for syntax and semantics. +
+Default is pass. +
+Insert mode works in conjunction with rotate and flip options.
+Any pre-existing Display orientation messages will be removed in insert or remove mode.
+Extract mode attaches the display matrix to the packet as side data.
+
Set rotation in display orientation SEI (anticlockwise angle in degrees). +Range is -360 to +360. Default is NaN. +
+Set flip in display orientation SEI. +
+Default is unset. +
+Set the level in the SPS. Refer to H.264 section A.3 and tables A-1 +to A-5. +
+The argument must be the name of a level (for example, ‘4.2’), a +level_idc value (for example, ‘42’), or the special name ‘auto’ +indicating that the filter should attempt to guess the level from the +input stream properties. +
+Convert an H.264 bitstream from length prefixed mode to start code +prefixed mode (as defined in the Annex B of the ITU-T H.264 +specification). +
+This is required by some streaming formats, typically the MPEG-2
+transport stream format (muxer mpegts).
+
For example to remux an MP4 file containing an H.264 stream to mpegts
+format with ffmpeg, you can use the command:
+
ffmpeg -i INPUT.mp4 -codec copy -bsf:v h264_mp4toannexb OUTPUT.ts +
Please note that this filter is auto-inserted for MPEG-TS (muxer
+mpegts) and raw H.264 (muxer h264) output formats.
+
This applies a specific fixup to some Blu-ray streams which contain +redundant PPSs modifying irrelevant parameters of the stream which +confuse other transformations which require correct extradata. +
+ +Modify metadata embedded in an HEVC stream. +
+Insert or remove AUD NAL units in all access units of the stream. +
+Set the sample aspect ratio in the stream in the VUI parameters. +
+Set the video format in the stream (see H.265 section E.3.1 and +table E.2). +
+Set the colour description in the stream (see H.265 section E.3.1 +and tables E.3, E.4 and E.5). +
+Set the chroma sample location in the stream (see H.265 section +E.3.1 and figure E.1). +
+Set the tick rate in the VPS and VUI parameters (time_scale / +num_units_in_tick). Combined with num_ticks_poc_diff_one, this can +set a constant framerate in the stream. Note that it is likely to be +overridden by container parameters when the stream is in a container. +
+Set poc_proportional_to_timing_flag in VPS and VUI and use this value +to set num_ticks_poc_diff_one_minus1 (see H.265 sections 7.4.3.1 and +E.3.1). Ignored if tick_rate is not also set. +
+Set the conformance window cropping offsets in the SPS. These values +will replace the current ones if the stream is already cropped. +
+These fields are set in pixels. Note that some sizes may not be +representable if the chroma is subsampled (H.265 section 7.4.3.2.1). +
+Set the level in the VPS and SPS. See H.265 section A.4 and tables +A.6 and A.7. +
+The argument must be the name of a level (for example, ‘5.1’), a +general_level_idc value (for example, ‘153’ for level 5.1), +or the special name ‘auto’ indicating that the filter should +attempt to guess the level from the input stream properties. +
+Convert an HEVC/H.265 bitstream from length prefixed mode to start code +prefixed mode (as defined in the Annex B of the ITU-T H.265 +specification). +
+This is required by some streaming formats, typically the MPEG-2
+transport stream format (muxer mpegts).
+
For example to remux an MP4 file containing an HEVC stream to mpegts
+format with ffmpeg, you can use the command:
+
ffmpeg -i INPUT.mp4 -codec copy -bsf:v hevc_mp4toannexb OUTPUT.ts +
Please note that this filter is auto-inserted for MPEG-TS (muxer
+mpegts) and raw HEVC/H.265 (muxer h265 or
+hevc) output formats.
+
Modifies the bitstream to fit in MOV and to be usable by the Final Cut +Pro decoder. This filter only applies to the mpeg2video codec, and is +likely not needed for Final Cut Pro 7 and newer with the appropriate +-tag:v. +
+For example, to remux 30 MB/sec NTSC IMX to MOV: +
+ffmpeg -i input.mxf -c copy -bsf:v imxdump -tag:v mx3n output.mov +
Convert MJPEG/AVI1 packets to full JPEG/JFIF packets. +
+MJPEG is a video codec wherein each video frame is essentially a +JPEG image. The individual frames can be extracted without loss, +e.g. by +
+ffmpeg -i ../some_mjpeg.avi -c:v copy frames_%d.jpg +
Unfortunately, these chunks are incomplete JPEG images, because +they lack the DHT segment required for decoding. Quoting from +http://www.digitalpreservation.gov/formats/fdd/fdd000063.shtml: +
+Avery Lee, writing in the rec.video.desktop newsgroup in 2001, +commented that "MJPEG, or at least the MJPEG in AVIs having the +MJPG fourcc, is restricted JPEG with a fixed – and *omitted* – +Huffman table. The JPEG must be YCbCr colorspace, it must be 4:2:2, +and it must use basic Huffman encoding, not arithmetic or +progressive. . . . You can indeed extract the MJPEG frames and +decode them with a regular JPEG decoder, but you have to prepend +the DHT segment to them, or else the decoder won’t have any idea +how to decompress the data. The exact table necessary is given in +the OpenDML spec." +
+This bitstream filter patches the header of frames extracted from an MJPEG +stream (carrying the AVI1 header ID and lacking a DHT segment) to +produce fully qualified JPEG images. +
+ffmpeg -i mjpeg-movie.avi -c:v copy -bsf:v mjpeg2jpeg frame_%d.jpg +exiftran -i -9 frame*.jpg +ffmpeg -i frame_%d.jpg -c:v copy rotated.avi +
Add an MJPEG A header to the bitstream, to enable decoding by +Quicktime. +
+ +Extract a representable text file from MOV subtitles, stripping the +metadata header from each subtitle packet. +
+See also the text2movsub filter. +
+ +Decompress non-standard compressed MP3 audio headers. +
+ +Modify metadata embedded in an MPEG-2 stream. +
+Set the display aspect ratio in the stream. +
+The following fixed values are supported: +
Any other value will result in square pixels being signalled instead +(see H.262 section 6.3.3 and table 6-3). +
+Set the frame rate in the stream. This is constructed from a table +of known values combined with a small multiplier and divisor - if +the supplied value is not exactly representable, the nearest +representable value will be used instead (see H.262 section 6.3.3 +and table 6-4). +
+Set the video format in the stream (see H.262 section 6.3.6 and +table 6-6). +
+Set the colour description in the stream (see H.262 section 6.3.6 +and tables 6-7, 6-8 and 6-9). +
+Unpack DivX-style packed B-frames. +
+DivX-style packed B-frames are not valid MPEG-4 and were only a +workaround for the broken Video for Windows subsystem. +They use more space, can cause minor AV sync issues, require more +CPU power to decode (unless the player has some decoded picture queue +to compensate the 2,0,2,0 frame per packet style) and cause +trouble if copied into a standard container like mp4 or mpeg-ps/ts, +because MPEG-4 decoders may not be able to decode them, since they are +not valid MPEG-4. +
+For example to fix an AVI file containing an MPEG-4 stream with
+DivX-style packed B-frames using ffmpeg, you can use the command:
+
ffmpeg -i INPUT.avi -codec copy -bsf:v mpeg4_unpack_bframes OUTPUT.avi +
Damages the contents of packets or simply drops them without damaging the +container. Can be used for fuzzing or testing error resilience/concealment. +
+Parameters: +
Accepts an expression whose evaluation per-packet determines how often bytes in that +packet will be modified. A value below 0 will result in a variable frequency. +Default is 0 which results in no modification. However, if neither amount nor drop is specified, +amount will be set to -1. See below for accepted variables. +
Accepts an expression evaluated per-packet whose value determines whether that packet is dropped. +Evaluation to a positive value results in the packet being dropped. Evaluation to a negative +value results in a variable chance of it being dropped, roughly inverse in proportion to the magnitude +of the value. Default is 0 which results in no drops. See below for accepted variables. +
Accepts a non-negative integer, which assigns a variable chance of it being dropped, roughly inverse
+in proportion to the value. Default is 0 which results in no drops. This option is kept for backwards
+compatibility and is equivalent to setting drop to a negative value with the same magnitude
+i.e. dropamount=4 is the same as drop=-4. Ignored if drop is also specified.
+
Both amount and drop accept expressions containing the following variables:
+
The index of the packet, starting from zero. +
The timebase for packet timestamps. +
Packet presentation timestamp. +
Packet decoding timestamp. +
Constant representing AV_NOPTS_VALUE. +
First non-AV_NOPTS_VALUE PTS seen in the stream. +
First non-AV_NOPTS_VALUE DTS seen in the stream. +
Packet duration, in timebase units. +
Packet position in input; may be -1 when unknown or not set. +
Packet size, in bytes. +
Whether packet is marked as a keyframe. +
A pseudo random integer, primarily derived from the content of packet payload. +
Apply modification to every byte but don’t drop any packets. +
ffmpeg -i INPUT -c copy -bsf noise=1 output.mkv +
Drop every video packet not marked as a keyframe after timestamp 30s but do not +modify any of the remaining packets. +
ffmpeg -i INPUT -c copy -bsf:v noise=drop='gt(t\,30)*not(key)' output.mkv +
Drop one second of audio every 10 seconds and add some random noise to the rest. +
ffmpeg -i INPUT -c copy -bsf:a noise=amount=-1:drop='between(mod(t\,10)\,9\,10)' output.mkv +
This bitstream filter passes the packets through unchanged. +
+ +Repacketize PCM audio to a fixed number of samples per packet or a fixed packet +rate per second. This is similar to the (ffmpeg-filters)asetnsamples audio +filter but works on audio packets instead of audio frames. +
+Set the number of samples per each output audio packet. The number is intended +as the number of samples per each channel. Default value is 1024. +
+If set to 1, the filter will pad the last audio packet with silence, so that it +will contain the same number of samples (or roughly the same number of samples, +see frame_rate) as the previous ones. Default value is 1. +
+This option makes the filter output a fixed number of packets per second instead +of a fixed number of samples per packet. If the audio sample rate is not +divisible by the frame rate then the number of samples will not be constant but +will vary slightly so that each packet will start as close to the frame +boundary as possible. Using this option has precedence over nb_out_samples. +
You can generate the well known 1602-1601-1602-1601-1602 pattern of 48kHz audio +for NTSC frame rate using the frame_rate option. +
ffmpeg -f lavfi -i sine=r=48000:d=1 -c pcm_s16le -bsf pcm_rechunk=r=30000/1001 -f framecrc - +
Merge a sequence of PGS Subtitle segments ending with an "end of display set" +segment into a single packet. +
+This is required by some containers that support PGS subtitles
+(muxer matroska).
+
Modify color property metadata embedded in prores stream. +
+Set the color primaries. +Available values are: +
+Keep the same color primaries property (default). +
+BT601 625 +
+BT601 525 +
+DCI P3 +
+P3 D65 +
+Set the color transfer. +Available values are: +
+Keep the same transfer characteristics property (default). +
+BT 601, BT 709, BT 2020 +
SMPTE ST 2084 +
ARIB STD-B67 +
Set the matrix coefficient. +Available values are: +
+Keep the same colorspace property (default). +
+BT 601 +
+Set Rec709 colorspace for each frame of the file +
ffmpeg -i INPUT -c copy -bsf:v prores_metadata=color_primaries=bt709:color_trc=bt709:colorspace=bt709 output.mov +
Set Hybrid Log-Gamma parameters for each frame of the file +
ffmpeg -i INPUT -c copy -bsf:v prores_metadata=color_primaries=bt2020:color_trc=arib-std-b67:colorspace=bt2020nc output.mov +
Remove extradata from packets. +
+It accepts the following parameter: +
Set which frame types to remove extradata from. +
+Remove extradata from non-keyframes only. +
+Remove extradata from keyframes only. +
+Remove extradata from all frames. +
+Set PTS and DTS in packets. +
+It accepts the following parameters: +
Set expressions for PTS, DTS or both. +
Set expression for duration. +
Set output time base. +
The expressions are evaluated through the eval API and can contain the following +constants: +
+The count of the input packet. Starting from 0. +
+The demux timestamp in input in case of ts or dts option or presentation
+timestamp in case of pts option.
+
The original position in the file of the packet, or undefined if undefined +for the current packet +
+The demux timestamp in input. +
+The presentation timestamp in input. +
+The duration in input. +
+The DTS of the first packet. +
+The PTS of the first packet. +
+The previous input DTS. +
+The previous input PTS. +
+The previous input duration. +
+The previous output DTS. +
+The previous output PTS. +
+The previous output duration. +
+The next input DTS. +
+The next input PTS. +
+The next input duration. +
+The timebase of stream packet belongs. +
+The output timebase. +
+The sample rate of stream packet belongs. +
+The AV_NOPTS_VALUE constant. +
Convert text subtitles to MOV subtitles (as used by the mov_text
+codec) with metadata headers.
+
See also the mov2textsub filter. +
+ +Log trace output containing all syntax elements in the coded stream +headers (everything above the level of individual coded blocks). +This can be useful for debugging low-level stream issues. +
+Supports AV1, H.264, H.265, (M)JPEG, MPEG-2 and VP9, but depending +on the build only a subset of these may be available. +
+ +Extract the core from a TrueHD stream, dropping ATMOS data. +
+ +Modify metadata embedded in a VP9 stream. +
+Set the color space value in the frame header. Note that any frame +set to RGB will be implicitly set to PC range and that RGB is +incompatible with profiles 0 and 2. +
Set the color range value in the frame header. Note that any value +imposed by the color space will take precedence over this value. +
Merge VP9 invisible (alt-ref) frames back into VP9 superframes. This +fixes merging of split/segmented VP9 streams where the alt-ref frame +was split from its visible counterpart. +
+ +Split VP9 superframes into single frames. +
+ +Given a VP9 stream with correct timestamps but possibly out of order, +insert additional show-existing-frame packets to correct the ordering. +
+ + +ffmpeg, ffplay, ffprobe, +libavcodec +
+ + +The FFmpeg developers. +
+For details about the authorship, see the Git history of the project
+(git://source.ffmpeg.org/ffmpeg), e.g. by typing the command
+git log in the FFmpeg source directory, or browsing the
+online repository at http://source.ffmpeg.org.
+
Maintainers for the specific components are listed in the file +MAINTAINERS in the source code tree. +
+ ++ This document was generated using makeinfo. +
+