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Babl CMYK-conversions

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Babl CMYK-conversions Alexander Hämmerle 23 Dec 10:26
  Babl CMYK-conversions Øyvind Kolås 24 Dec 04:44
Alexander Hämmerle
2011-12-23 10:26:09 UTC (over 13 years ago)

Babl CMYK-conversions

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

Øyvind Kolås
2011-12-24 04:44:11 UTC (over 13 years ago)

Babl CMYK-conversions

On Fri, Dec 23, 2011 at 10:26 AM, Alexander H