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Aman Gupta
2b2f2f65f3
avformat: add fields to AVProgram/AVStream for PMT change tracking
These fields will allow the mpegts demuxer to expose details about the PMT/program which created the AVProgram and its AVStreams. In mpegts, a PMT which advertises streams has a version number which can be incremented at any time. When the version changes, the pids which correspond to each of it's streams can also change. Since ffmpeg creates a new AVStream per pid by default, an API user needs the ability to (a) detect when the PMT changed, and (b) tell which AVStream were added to replace earlier streams. This has been a long-standing issue with ffmpeg's handling of mpegts streams with PMT changes, and I found two related patches in the wild that attempt to solve the same problem: The first is in MythTV's ffmpeg fork, where they added a void (*streams_changed)(void*); to AVFormatContext and call it from their fork of the mpegts demuxer whenever the PMT changes. The second was proposed by XBMC in https://ffmpeg.org/pipermail/ffmpeg-devel/2012-December/135036.html, where they created a new AVMEDIA_TYPE_DATA stream with id=0 and attempted to send packets to it whenever the PMT changed. Signed-off-by: Aman Gupta <aman@tmm1.net>
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FFmpeg README
FFmpeg is a collection of libraries and tools to process multimedia content such as audio, video, subtitles and related metadata.
Libraries
libavcodec
provides implementation of a wider range of codecs.libavformat
implements streaming protocols, container formats and basic I/O access.libavutil
includes hashers, decompressors and miscellaneous utility functions.libavfilter
provides a mean to alter decoded Audio and Video through chain of filters.libavdevice
provides an abstraction to access capture and playback devices.libswresample
implements audio mixing and resampling routines.libswscale
implements color conversion and scaling routines.
Tools
- ffmpeg is a command line toolbox to manipulate, convert and stream multimedia content.
- ffplay is a minimalistic multimedia player.
- ffprobe is a simple analysis tool to inspect multimedia content.
- Additional small tools such as
aviocat
,ismindex
andqt-faststart
.
Documentation
The offline documentation is available in the doc/ directory.
The online documentation is available in the main website and in the wiki.
Examples
Coding examples are available in the doc/examples directory.
License
FFmpeg codebase is mainly LGPL-licensed with optional components licensed under GPL. Please refer to the LICENSE file for detailed information.
Contributing
Patches should be submitted to the ffmpeg-devel mailing list using
git format-patch
or git send-email
. Github pull requests should be
avoided because they are not part of our review process and will be ignored.
Languages
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0.2%
Other
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