Quote:
Originally Posted by feisty2
I know exactly what range means. if you're talking about 8-bit limited range, any behavior on (236,128,128) is undefined because it is not in the (definition) domain.
this is called analytic continuation, basically you have extended the domain of the original definition, and whatever happens in the extended domain has nothing to do with the original definition. do you know that the sum of all natural numbers converges to -1/12?
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You can call it undefined, but it happens, and those code values can exist.
Do you see why limited range RGB exists, and why limiting functions are sometimes used ? It's to conform to 709 specs , and r103
But the problem is many of those "illegal" broadcast values are illegal combinations of Y,Cb,Cr that result in negative or >1 values in RGB in the [0,1] definition (they lie outside the RGB color cube) . They lie in the middle of the range and cannot be addressed by simple min/max compression or clipping adjustments
Simple manipluations like resizing, chroma subsampling can result in those illegal values.