[FFmpeg-devel] [bug/patch] MPEG-TS muxer: PCR not in sync withPTS/DTS

Mike Scheutzow scheutzow
Mon Nov 16 16:34:50 CET 2009

Stratford, Alan wrote:
> The PCR values ranged from roughly 0 to 277 seconds,
> which seems very wrong for a 10 second clip. out.ts played ok in ffplay,
> but would not play in vlc.

The 'mpegts' demux discards all PCRs from the transport stream. So even 
if the PCRs are totally wrong, ffplay will still play ok.

> I have tried other options on the command line, such as -muxrate to
> generate a CBR output, which affect the PCR values but they always start
> a roughly 0 and end at a much higher value than the expected 10 seconds.
> If the -copyts is omitted from the above command then the PCR and PTS
> seem OK, i.e. they both start at roughly 0 seconds and end at roughly 10
> seconds.

There is no code in the mpegts mux to calculate a reasonable starting 
value for PCR if -copyts is used.

Mike Scheutzow

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