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

[Holger Waechtler]

--- Lourens Veen <jsr at dds.nl> 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?

You are right, it should be 

u = r - g
v = g - b
y = g + 1/4 * (u-v)
  = g + 1/4 * (r-g-g+b)
  = g + 1/4 * r - 1/2 * g + 1/4 * b
  = r/4 + g/2 + b/4                                                    
        

I'll fix this tonight.

- Holger

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