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> "Bald Eagle" <cre### [at] netscape net> wrote:
> >
> > The new tone-adjusting formulas are:
> >
> > #declare SRGB_Encode = function (C, M) {
> > select (C-0.0031308, C*12.92*M, C*12.92*M, (1.055 * pow (C, 1/2.4) - 0.055)*M)
> > }
> >
> > #declare SRGB_Decode = function (C, M) {
> > select (C-0.040449936, C/12.92, pow ((C+0.055)/1.055, 2.4)*M)
> > }
> >
> > using M as a multiplier. Looks like it works correctly, even with M > 1.
> > Perhaps it's not "right", but it's the way I envisioned its usage.
> >
>
[off-topic, sort of...]
Here's some food for thought, which just occured to me-- not about your
functions, but about the conversion formulae themselves (Wikipedia and
elsewhere):
The conversion formulae use a "2.4 gamma" in the computations-- whereas, in
POV-ray, and running antialiasing in a scene, Clipka chose a "2.5 gamma" for the
antialiasing gamma (this in v3.8xx). Maybe I'm cluelessly 'comparing apples to
oranges', but I wonder why Clipka didn't choose "2.4 gamma" instead? I suppose
there *is* a reason, but... :-O
Just something to keep you and me up at nights, wondering about the
difference... ;-)
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