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Posted by Jeckyl on 01/16/07 03:40
> *tries clicking the link for "alpha premultiplied" and crosses
> fingers*
>
> :If an alpha channel is used in an image, it is common to also multiply
> :the color by the alpha value, in order to save on additional
> :multiplications during the compositing process. This is usually
> :referred to as premultiplied alpha. Thus, assuming that the pixel
> :color is expressed using RGB triples, a pixel value of (0.0, 0.5, 0.0,
> :0.5) implies a pixel which is fully green and has 50% coverage.
>
> ...wow...even Wikipedia FAILS to explain it
It just did .. READ IT
> with anything other than
> the most simplistic glazing jive of redundant incoherency. Tsch,
> tsch, tsch
For someone who uses big words, you seem to understand very little.
>...a simple formula/equation is just TOO MUCH to ask
> apparently. Oh how the mighty web has fallen.
Duh!!! You multiply .. there isn't some complicated formula or magic
equation .. its just simply multiplication.
eg. (for the chronically stupid)
ie the rgb value was (20,80,240) and the alpha was 50% (0.5), then you
multiple each of the R,G and B values by 0.5 to get (10,40,120).
See .. blindinly obvious.
--
Jeckyl
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