[FFmpeg-trac] #8039(avformat:new): mpegtsenc: incorrect PCR with multiple programs
FFmpeg
trac at avcodec.org
Thu Jul 25 09:55:27 EEST 2019
#8039: mpegtsenc: incorrect PCR with multiple programs
-----------------------------------+--------------------------------------
Reporter: ahakon | Type: defect
Status: new | Priority: important
Component: avformat | Version: git-master
Keywords: mpegtsenc | Blocked By:
Blocking: | Reproduced by developer: 0
Analyzed by developer: 0 |
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Summary of the bug:
The MPEG-TS muxer has a '''serious''' bug related to the PCR pid
selection.
This bug appears when more than one program is used. The root cause is
because
the current code targets only one program when selecting the stream for
the PCR.
How to reproduce:
[ test file "Day_Flight.mpg" from
https://samples.ffmpeg.org/MPEG2/mpegts-klv/Day%20Flight.mpg ]
{{{
% ffmpeg -loglevel verbose -y -f mpegts -i Day_Flight.mpg \
-map i:0x1e1 -c:v:0 copy -map i:0x1e1 -c:v:1 copy \
-program st=0 -program st=1 -f mpegts out-error.ts
}}}
If you analyze the output, you can see that the file "out-error.ts" has
PCR
marks in every packet of the pid 256 (a total of 561862 packets with PCR
marks).
However, the pid 257 has 783 packets only with PCR marks.
Current source code of the mpegts muxer only initializes the PCR of one
program. Other programs are unintialized. And this is a bug.
Regards.
A.H.
--
Ticket URL: <https://trac.ffmpeg.org/ticket/8039>
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