Re: [Algorithms] RGB to XYZ conversion

[Wolfgang E. <wol...@gm...>]

I used this for PostFX. The equation I use is different from yours.  
The color values that go in there are already gamma 1.0.
I posted my numbers on my blog

Diaryofagraphicsprogrammer.blogspot.com

I can't remember how I came up with them but it was probably not a  
scientific way.

Sent from my iPhone

On Apr 21, 2008, at 10:04 AM, chr...@pl...  
wrote:

>
> Dan Glastonbury wrote:
>> Dear colour space experts
>> What matrix should I being using to convert RGB values to CIE XYZ?
>> Christer Ericson (http://realtimecollisiondetection.net/blog/?p=15)
>> gives the following matrix:
>>
>>  M = [0.497,0.339,0.164]
>>      [0.256,0.678,0.066]
>>      [0.023,0.113,0.864]
>>
>> to be used in [X Y Z] = [R G B]*M and I assume this comes from Greg
>> Ward's paper.  Charles Poynton's ColorFAQ and wikipedia's article on
>> CIE 1931 give different formulations for the conversion.
>
> Good question Dan, and I for one don't know the answer. I asked myself
> the same question when I wrote that blog post and first worked out the
> code. Everywhere you look, there's another subtly different matrix
> given. As we didn't end up using any logluv encodings, I never tried
> to find out what's the "correct" matrix. As you correctly assumed, I
> just used the values given in Greg Ward's paper for the blog post.
>
>
> Christer Ericson, Director of Tools and Technology
> Sony Computer Entertainment, Santa Monica
> http://realtimecollisiondetection.net/blog/
>
>
> --- 
> ----------------------------------------------------------------------
> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference
> Don't miss this year's exciting event. There's still time to save  
> $100.
> Use priority code J8TL2D2.
> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone
> _______________________________________________
> GDAlgorithms-list mailing list
> GDA...@li...
> https://lists.sourceforge.net/lists/listinfo/gdalgorithms-list
> Archives:
> http://sourceforge.net/mailarchive/forum.php?forum_name=gdalgorithms-list