[FFmpeg-devel] [RFC] Format of packets for text subtitles

Wolfram Gloger wmglo at dent.med.uni-muenchen.de
Fri Jun 8 15:50:19 CEST 2012


Nicolas George <nicolas.george at normalesup.org> writes:

> It would be much more problematic if you knew a format that can contain text
> subtitles interleaved with video and that relies on that trick to mark the
> end of a subtitle,

My example would be mpeg-ts with a teletext subtitle, or with a dvb
subtitle (though that is bitmap).  No duration known until the next
(possibly empty) subtitle packet.

> because we can not afford to buffer several seconds worth
> of stream just to find the duration information.

Why can't we?  There simply is no other way.  Teletext/DVB subtitles are
in practice never longer than 20sec, at least I haven't seen any.

Regards,
Wolfram.


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