From: Joel de Guzman (joel_at_[hidden])
Date: 2006-11-01 06:56:26
Fernando Cacciola wrote:
> Joel de Guzman wrote:
>> Joel de Guzman wrote:
>>> Matt Gruenke wrote:
>>>> Joel de Guzman wrote:
>>>>> I disagree. A color space is a tuple of numbers. It is concerned with
>>>>> data and layout as far as I can see. That is the very definition of
>>>> That's a color (or pixel value).
>>>> A color space provides the semantics of these numbers, possibly
>>>> including how they are converted to other color spaces. This may
>>>> include its basis, CIE primaries, transfer function, gamut, etc. (For
>>>> more information, here's a good starting point:
>>>> http://www.poynton.com/notes/colour_and_gamma/ColorFAQ.html )
>>>> A pixel format establishes the mapping between channels of an image
>>>> (i.e. color, pixel value, etc.) and components of a color space.
>>> Now I see the confusion. There are overlaps in the definition of
>>> colors and color-spaces of course. Did you think they were orthogonal?
>>> See: http://tinyurl.com/18r for the definition of color-spaces.
>> tinyurl mistake again! One more try:
> That very same wikipedia article may be used to explain why Matt and I
> are against using the term "color space" for the GIL element under
> If you read it carefully you can see that the "tuple of numbers" is a
> "color model", not a "color space" (a mapping function binds the model
> with the space)
> Reading further down you see that it refers to "RGB", "CYMK", etc as
> color models, not color spaces.
> So at most I would say that the correct term is color model. It
> certainly isn't color space and that article shows why quite well.
No! Read carefully. Color space is gamut (footprint) + color model.
-- Joel de Guzman http://www.boost-consulting.com http://spirit.sf.net
Boost list run by bdawes at acm.org, gregod at cs.rpi.edu, cpdaniel at pacbell.net, john at johnmaddock.co.uk