[FFmpeg-cvslog] r11627 - trunk/libavformat/mov.c

[Måns Rullgård]

Reimar D?ffinger <Reimar.Doeffinger at stud.uni-karlsruhe.de> writes:

> Hello,
> On Sun, Jan 27, 2008 at 06:39:39PM +0000, M?ns Rullg?rd wrote:
>> Reimar D?ffinger <Reimar.Doeffinger at stud.uni-karlsruhe.de> writes:
>> > On Sun, Jan 27, 2008 at 07:21:02PM +0100, Baptiste Coudurier wrote:
>> >> Humm here without the commit:
>> >> ffmpeg -i unsupported-embedded-subs-2.mp4 -scodec copy test.vob
>> >> 
>> >> then mplayer displays subs correctly (with weird font though). I
>> >> remember that nero stores some extradata similar to what .ifo contains
>> >> in dvds, in esds.
>> >> 
>> >> So I guess for complete support, extradata should be extracted, I
>> >> remember a patch for that in ffmpeg-devel to support palette for subs in
>> >> mkv, and IIRC reimar have something like that in mplayer, which can be
>> >> ported to lavc, maybe Im wrong though.
>> >
>> > I am not sure about matroska, but Nero just stores the 16*4 bytes
>> > palette in the extradata, nothing special.
>> 
>> That actually makes sense, as it is exactly what the decoder needs.
>> IMHO this should be considered the "native" extradata format for DVD
>> subtitles, and any container using a different format should have it
>> converted by the demuxer.
>
> I also should add it is in YUVA format, not RGB. I assume they used the
> correct formula for conversion, but I am not sure, that broken RGB->YUV
> conversion formula (that "almost" swaps U and V) has become very popular
> for vobsub.

I'd expect real DVDs to have it right.  It's hard to tell for sure,
since subtitles tend to be black and white only.

-- 
M?ns Rullg?rd
mans at mansr.com