[MPlayer-dev-eng] PGS subtitles vanish/disappear immediately in m2ts

[Reimar Döffinger]

On Sat, Sep 15, 2012 at 07:14:32PM +0200, Nicolas George wrote:
> Le decadi 30 fructidor, an CCXX, Reimar Döffinger a écrit :
> > This seems broken to me,
> 
> Isn't that true about anything that comes out as an "industrial standard"?
> 
> >			   since PGS does not have B-frames the pts
> > should never be moving backwards (and whether it should differ from dts
> > is up to discussion as well I guess).
> 
> I agree on principle. The multiple packets with the same DTS are also an
> issue.

I don't really consider that really an issue.

> But is there any other option than to accept it as a fact and deal with it?
> The file exists, and I gathered the issue is not so uncommon.

Well, it would be possible to override the pts for these packets already
in the demuxer, though a parser might be a more generic way to do it.
Depends on whether that issue exists only with ts or also with PGS muxed
into e.g. Matroska (if that exists).

> Maybe a parser could help. I am not yet quite clear about parsers, but it
> seems they can merge several packets (even when they are not contiguous) and
> fix timestamps.

Parsers that merge packets are slightly more expensive and they would
probably make remuxing more difficult.

> Do you have pointers to other samples with PGS subtitles?

Any BluRay?
Also, http://samples.mplayerhq.hu/sub/PGS/ maybe
http://samples.mplayerhq.hu/sub/BluRay/ (not sure what that is actually)
Possibly http://samples.mplayerhq.hu/bluray/