Re: Correct implementation of RGB channel decorrelation

As said above, having 8 bit channels R-G and B-G would require 9 bits.
So, how can manage negatives?

Having 9-bit samples is quite typical in these cases, some transforms
even obtain 10 bit channels. Anyway in the case of G, R-G and B-G you
should be able to use the remainder of the division by 256 to keep
values in the 0-255 interval, but as it has been suggested the
drawback could be that the decorrelation is less effective than with
other transforms.

If you do not expect some particular values in the next phases of the
algorithm, a remapping will not help: characteristics of the image as
enthropy and variance would not change.

So long,
Stefano
.

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