[vorbis-dev] Integer wavelet video codec (source and test program)

[Martin C. Martin]

Hmm, that's not the formula I'm familiar with.  YUV comes to us from
color television.  When color was introduced, everyone still had black
and white TVs, so it had to be backwards compatible.  Therefore, they
ued the following formula:

.299 r + .587 g + .114 b

That more or less corresponds to the sensitivity of our eyes.

I don't have the formulas for U and V here, I could look them up if
you really need them.

- Martin

On Wed, 7 Feb 2001, Lourens Veen wrote:

> Hi,
> 
> I have a question about the yuv->rgb and rgb->yuv formulas. They work
> out to:
> 
> u = r - g;
> v = g - b;
> y = g + 1/4*r + 1/4*b;
> 
> I understand that green is generally more important than blue and red
> but isn't this a bit radical?
> 
> Lourens
> 
> 
> Holger Waechtler wrote:
> > 
> > Hi everybody,
> > 
> > I wrote last time some code to do video compression using a 3d integer
> > wavelet transform. Since it uses a reversible lifting scheme and avoids a
> > lot of floating point operations compared to Jacks initial Tarkin code,
> > this should be somewhat faster and allow lossy+lossless compression.
> > 
> > The current implementation is very experimental, but nevertheless I would
> > be happy if some of you would take a look on the source available at
> > http://www.informatik.hu-berlin.de/~waechtle/w3d-0.1.14.tar.gz (about 9k).
> > 
> > Comments, ideas, help and contributions are always welcome.
> > Please cc me in replies, I'm not subscribed on this list.
> > 
> > - Holger
> 
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