Re: Analogue artifact estimation

Lourens Veen wrote:
> 
> On Sunday 01 September 2002 10:54, [email protected] wrote:
> > I originally posted these ideas to the Theora developers list, but
> > they suggested that this list might be more appropriate, (I thought
> > that the Tarkin project had died off :-) )
>
> [..] We've had longer periods of inactivity before, and then someone
> mails something and it flares up again. Or not. :-).

Just because a list is silent does not mean that the people on it are
not working on different things in their own corners of the universe. :-)

> > > Just batting a few ideas around here, but would it be possible
> > > to include in to the codec, estimation for common video
> > > artifacts that occur in the analogue world?
> 
> That's interesting. If we can recognise them we could probably even
> compensate for them as well. Ofcourse, for certain artifacts the
> original information is simply missing so the best we can do is try
> and synthesise something.

Don't forget transcoding from MPEG or DV to Tarkin.
Apart from the "raw" codec, a good encoder/transcoder should also be doing
artifact reduction and perceptually-guided quantization, IMHO.
Naturally, a lot of research has been done in reducing DCT artifacts.

> [...]
> > > Infact, existing video compression codecs do a *terrible* job
> > > of encoding hand painted animation, especially anime, despite
> > > claims by well known studios that it is not an issue.  Good
> > > motion estimation to compensate for poor registration of
> > > animation would be worth investigating.
> 
> Agreed, simple RLE does a lot better than MPEG on cartoons for
> example. However, I think cartoons are better off with a separate
> codec that's optimised for that. Probably something that can
> extract curves and surfaces and store them efficiently.

Go search on citeseer for "ridgelets", "wedgelets" and "bandelets".
These are new lifting transforms for representing edges in a multiple
resolutions, inspired by the wavelet transform and its inability to
represent hard edges efficiently.

/ Johan
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