[mythtv] GOP_BYFRAME vs. GOP_START and mythcommflag --rebuild
level42 at sympatico.ca
Tue Jun 5 05:58:43 UTC 2007
Agreed about the decoders. Thanks for the clarification.
I've been looking at making a patch, to convert to use only GOP_BYFRAME, but
don't know what to do with the code
bool is_ivtv = (keyframedist == 15) || (keyframedist ==12);
positionMapType = (is_ivtv) ? MARK_GOP_START : MARK_GOP_BYFRAME;
in HandleGopStart in avformatdecoder.cpp.
I would tend to set keyframedist=1 and positionMapType=MARK_GOP_BYFRAME for
everything in both HandleGopStart and Openfile, but not sure about the ivtv
thing. I believe that these changes would allow mythcommflag to generate a
good position map.
I have a sneaking suspision that making these changes will help improve
seeking on mpg's without position maps, since the position map is stored
incorrectly if keyframdist is greater than 1 and changes during playback and
when the positionMapType gets set to MARK_GOP_BYFRAME.
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