diff options
| author | Aman Gupta <aman@tmm1.net> | 2018-05-17 15:30:21 -0700 |
|---|---|---|
| committer | Aman Gupta <aman@tmm1.net> | 2018-05-18 19:00:29 -0700 |
| commit | 2b2f2f65f38cdd64fe126079f84872c0b06c6afc (patch) | |
| tree | b3356e212f2d547ca246d6724ddcfc3cac44c0dc /doc | |
| parent | 79126ce80e21f2bc986fef7b8f0d6335136538da (diff) | |
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>
Diffstat (limited to 'doc')
| -rw-r--r-- | doc/APIchanges | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/doc/APIchanges b/doc/APIchanges index befa58c84a..a592073ca5 100644 --- a/doc/APIchanges +++ b/doc/APIchanges @@ -15,6 +15,10 @@ libavutil: 2017-10-21 API changes, most recent first: +2018-05-xx - xxxxxxxxxx - lavf 58.15.100 - avformat.h + Add pmt_version field to AVProgram + Add program_num, pmt_version, pmt_stream_idx to AVStream + 2018-05-xx - xxxxxxxxxx - lavf 58.14.100 - avformat.h Add AV_DISPOSITION_STILL_IMAGE |