[FFmpeg-devel] [PATCH 12/12] tools/dvd2concat: generate VOBSUB extradata

[Andreas Rheinhardt]

Nicolas George:
> Nicolas George (12021-08-31):
>> For muxing the subtitles, some more work to be done, probably: mencoder
>> is still needed.
> 
> With Matroska output:
> 
> With -c:s dvd_subtitle it works, and the subtitles packets are much
> smaller. But I am not 100% confident in our encoder, it tries to guess
> which parts are the body of the letters and which parts are the outline.
> 
> With -c:s copy, the resulting file has no duration on the subtitles,
> which IIRC is not valid, but mkvalidator does not complain. mkvmerge can
> fix the file.
> 

Our VobSub demuxer does not set the duration (it is encoded as part of
the payload). So our muxer uses SimpleBlocks (because duration == 0
actually says "play this until the next packet arrives", which coincides
with the semantics for SimpleBlocks).
mkvmerge reads the duration from the payload.
Is there a proper spec for the VobSub format somewhere?

- Andreas