Some day I might figure out how to use email. In the meantime, here's the rest of what should have been part of the previous email: > but the meta data > passed around in terms of bablformats in the GeglBuffer will still > state that this is sRGB data, and when gegl:gaussian-blur is blurring > it that sRGB data will be converted to linear light data for the > actual blurring. Are you saying is that babl/gegl always acts as if any image opened by Gimp is really in the regular sRGB color space, with sRGB's peculiar "almost gamma=2.2" tone response curve? Or that if the image is created by Gimp, even after a diffferent ICC profile is assigned, that babl/gegl still assumes that the image is an sRGB image, with the peculiar sRGB tone response curve? What I would have assumed would happen, is that "behind the scenes" gegl/babl creates (something like a) linear scRGB version of the image (by literally converting the image *from* whatever RGB color space it happens to be in *to* the scRGB color space) and then applies the gegl/babl gaussian blur to the *converted* image (not to the original image). If what I just described is what really happened, then there would be no gamma error during the gegl gaussian blur. The linear gamma image would be converted to linear scRGB "behind the scenes", blurred correctly, and converted back to the original linear gamma profile upon exporting the image. And the regular gamma image would be converted to linear scRGB "behind the scenes", blurred correctly, and converted back to the original regular gamma profile upon exporting the image. But what really seems to be happening is that gegl/babl assumes all images have the sRGB not-quite-gamma-2.2 tone response curve, regardless of the image profile's actual tone response curve. In other words, there doesn't seem to be any "behind the scenes" converting *from* the ICC profile the image has upon opening, *to* the babl/gegl internal working space, before the gegl operation is applied to the image. -- http://ninedegreesbelow.com Articles and tutorials on open source digital imaging and photography _______________________________________________ gimp-developer-list mailing list gimp-developer-list@xxxxxxxxx https://mail.gnome.org/mailman/listinfo/gimp-developer-list
