FFmpeg document 19-bit stream filter

19-Bit Stream filter

All bitstream filters are supported by default compilation, and you can --list-bsfs get a list of valid filters in the configuration script

can take advantage--disable-bsfsDisables all bit-stream filters. To specify that individual filters are available, on this basis--enable-bsf=BSF, or in the default (no specified--disable-bsfs) To disable individual filters under--disable-bsf=BSFOver hereBSFis the individual filter name.

In the ff* toolset, -bsfs you can list supported Bitstream filters (which are allowed for compilation).

In the Ff* toolset, -bsf options can specify filters to be applied to each stream, with the filter name 1 = option Name 1 = option value 1/Option Name 2 = option value 2 ... ' Given, for example

ffmpeg -i INPUT -c:v copy -bsf:v filter1[=opt1=str1/opt2=str2][,filter2] OUTPUT

Here are some of the currently active Bitstream filters

AAC ADTSTOASC

Convert MPEG-2/4 's AAC ADTS to MPEG-4 Audio's dedicated configuration bitstream filter.

This filter creates a dedicated MPEG-4 audio configuration stream that removes Adts headers from the Adts head of MPEG-2/4

This is necessary, for example, when copying AAC audio content converted from raw Adts to a flv/mov/mp4 file, such processing is required

Chomp

Remove the additional 0 after each package

Dump extra

Add Extradata to the start of the filter pack

Additional parameters specify how to handle them, like the following possible values:

• ' a '

• ' K '

• ' E '

to each package

If it is not specifiedk

For example, the following ffmpeg enforces the global header (disabling the separate header) in encoding h., adding global headers to add as Extradata to remediate each packet

ffmpeg -i INPUT -map 0 -flags:v +global_header -c:v libx264 -bsf:v dump_extra out.ts

H264_mp4toannexb

Convert h. Encode bitstream, from long preamble mode to start code preamble (defined in Appendix B of ITU-T H. c)

It is required for some stream formats, typically such as the MPEG-2 Transport stream format ("Mpegts")

For example, using FFmpeg to re-mash a h. MP4 file, change the flow to mpegts format, you can use:

ffmpeg -i INPUT.mp4 -codec copy -bsf:v h264_mp4toannexb OUTPUT.ts

Imxdump

Fixed to editable bit stream mov format for final Cut Pro decoding. This filter is for Mpeg2video encoding only, and for the following versions of final Cut Pro 7, use the -tag：v option

For example, re-30mb/sec the NTSC IMX to MOV:

ffmpeg -i input.mxf -c copy -bsf:v imxdump -tag:v mx3n output.mov

Mjpeg2jpeg

Convert MJPEG/AVI1 package to full JPEG/JFIF package

MJPEG is a video encoding, which is basically a JPEG image per frame, which can be extracted directly without any damage, such as:

ffmpeg -i ../some_mjpeg.avi -c:v copy frames_%d.jpg

Unfortunately, these blocks are incomplete JPEG images because they lack the DHT segments required for decoding.
Http://www.digitalpreservation.gov/formats/fdd/fdd000063.shtml:

avery Lee, writing in the Rec.video.desktop newsgroup in 2001, commented ' MJPEG, or at least ' MJPEG in AVIs havin G The MJPG FourCC, is restricted JPEG with a fixed–and *omitted*–huffman table. The JPEG must is YCbCr colorspace, it must be 4:2:2, and it must with 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 Segme NT to them, or else the decoder won ' t has any idea how to decompress the data. The exact table necessary is given in the OPENDML spec. " 

This bitstream filter can extend the repair mjpeg stream (carrying AVI1 header ID, but missing DHT segments) as a full JPEG image

ffmpeg -i mjpeg-movie.avi -c:v copy -bsf:v mjpeg2jpeg frame_%d.jpgexiftran -i -9 frame*.jpgffmpeg -i frame_%d.jpg -c:v copy rotated.avi

Mjpega dump Headermovsubmp3 Head decompression MPEG4 unpack Bframes

Unpack the B-frame of DivX package

DivX-style B-frames are invalid MPEG-4, and are used only for the fragmented solution of Windows systems, which use more space and can look at causing minor AV synchronization problems, requiring more CPU resources for decoding (unless playback takes some 2,0,2,0 frame grouping), If copying directly into a MP4 standard package or MPEG Ps/ts stream will cause a problem (MPEG-4 cannot decode correctly because it is not a valid MPEG-4 encoded data)

For example, fix an AVI file containing DivX-style B-frame data to the MPEG-4 stream, which can be used:

ffmpeg -i INPUT.avi -codec copy -bsf:v mpeg4_unpack_bframes OUTPUT.avi

Noise

Do not destroy the container, only the content package. Typically used to freeze or test error recovery/hiding

Parameters: A numeric string whose value is usually modified by the output, so values less than or equal to 0 are forbidden. Bytes below the update frequency are modified, and 1 indicates that each byte is modified.

ffmpeg -i INPUT -c copy -bsf noise[=1] output.mkv

Indicates that each byte has been modified.

Remove extra

FFmpeg document 19-bit stream filter