[FFmpeg-devel] [PATCH] attachments support in matroska demuxer

Rich Felker dalias
Thu Jan 3 04:29:34 CET 2008

On Wed, Jan 02, 2008 at 06:45:44PM -0700, Loren Merritt wrote:
> On Wed, 2 Jan 2008, Rich Felker wrote:
> > On Wed, Jan 02, 2008 at 06:49:28AM +0200, Uoti Urpala wrote:
> >>
> >> Extradata may happen to be identical, but subtitles can refer to "the
> >> same font" in a stricter sense. If you demux a .mkv file into separate
> >> files, a natural format is to have an audio file (or files), a video
> >> file, a .ssa/.ass file (or files) and a bunch of font files. Nobody
> >> splits video/audio tracks into separate "standard extradata" and "main
> >> content" parts.
> >
> > I agree here too. Most subtitle 'codecs' already have an extradata
> > format of their own, text-based, separate from the binary ttf data.
> > Most likely it's the "header text" which would appear at the beginning
> > of the subtitle file if it were flat text. So it would be rather
> > problematic to try to munge the fonts together with this...
> You can put fonts in SSA extradata, using a variant of uuencoding. I 
> haven't seen this recently, but I have some movies using this from before 
> matroska.

Ahh, perhaps the mkv demuxer should translate them and append them to
the extradata like this. At least then it's some kind of sane,
standard format.


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