Hi,
> we are trying to use the "Perserve Black functionality" using version 1.18. I *highly* encourage you to upgrade to 2.6, or any 2.x if possible. Black preservation didn't work well in 1. branch. Version 2.x have exactly what you want, selected as extra intents: INTENT_PRESERVE_K_ONLY_PERCEPTUAL INTENT_PRESERVE_K_ONLY_RELATIVE_COLORIMETRIC and INTENT_PRESERVE_K_ONLY_SATURATION This is the "soft" algorithm, which only does reverse interpolation on K. Basically you need to compute a curve of equivalences K to K', which is obtained by using the reverse CMYK->Lab direction of both input and output profiles. K to L* in this case. Then if CMY is zero, the black preserving transform interpolates K' from K, otherwise it reverts to normal transform. That is all. Fair more complex is when you try to preserve the whole K plane, which needs reverse 3D interpolation. In 1.18 there was only one black preserving mode and as said it didn't work well. On 2.x you have both and they work to me. I've successfully used the transforms in many applications. The translator, for example. Regards Marti ------------------------------------------------------------------------------ Learn Graph Databases - Download FREE O'Reilly Book "Graph Databases" is the definitive new guide to graph databases and their applications. Written by three acclaimed leaders in the field, this first edition is now available. Download your free book today! http://p.sf.net/sfu/13534_NeoTech _______________________________________________ Lcms-user mailing list Lcms-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/lcms-user
