[vorbis-dev] video codec

[Ralph Giles]

On Sat, 10 Feb 2001, Holger Waechtler wrote:

> > Here's something I'd like to see in a video codec.  When I encode video
> > with e.g. MPEG or RealVideo, there's one thing that's really obnoxious. 
> > If I have a still portion of an image and a moving portion (for example, a
> > title over moving video), basically every low bitrate codec I've seen
> > sucks at representing it.  The title sort of blurs into the video,
> > resulting in unreadable test and a rather poor representation of the
> > background video as a consequence

The real solution to this is to encode such titles in a separate, lossless 
overlay layer. But it's also something wavelets should be better at.

> Can you supply a test case ?  -- then you can be pretty shure that this
> case will be checked. Please contact Ralph (I really hope, he'll take the
> disk admin job;-) ...

Pretty much anything with large titling will show this.

> I'm still in hope we won't need too many special case encoders - It's
> much easier to maintain one general codec.

Don't know if you were around the last time this was discussed. I'd
suggested using ogg-encapsulated mng in a separate substrate for overlays.
We need that for dvd-style multilingual subtitles anyway, and it adds a
lot of creative and educational flexibility. Of course we should try to be
as general as possible, but the video codec should concentrate on natural
video and film sources, I think. 

Cheers,
 -ralph

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