[Gimp-developer] Babl CMYK-conversions

[Alexander Hämmerle <Alexander Haemmerle gmx de>]

Hi,

there seem to be some quirks in babl.

1) ./babl/base/model-cmyk.c

In the cmyk_to_rgb-function the components are assigned from the source in an 
erroneous order. Obviously in the CMYK-colorspace magenta is the second color. 
Here yellow takes its place and magenta is the third one.

double cyan    = ((double *) src)[0];
double yellow  = ((double *) src)[1];
double magenta = ((double *) src)[2];
double key     = ((double *) src)[3];

2) ./babl/extensions/naive-CMYK.c

For what reason is there a second implementation of essentially the same code 
as you find it in model-cmyk.c in the file naive-CMYK.c? The only difference 
seems to be that model-cmyk.c makes the conversion RGB->CMYK and naive-CMYK.c 
implements RGBA->CMYK.
Wouldn't it be more comprehensive to have it all in one place? Or is RGB->CMYK 
the more basic conversion? I thought in Babl the RGBA-space were something 
like a reference.

3) More stunning for me: model-cmyk.c exists only in the GIT clone from 
git://git.gnome.org/babl but not in the downloaded tar.bz2 from 
ftp.gtk.org/pub/babl :-?

Sorry for my lack of understanding,
Alex