Hi Louis, That's a very interesting topic. LittleCMS 2 has control on the degree of chromatic adaptation, tificc defaults to it to 0 (no adaptation). If you set it to 1 to obtain ICC-Absolute intent, you will get same results as WCS. Use -d1 to specify full adaptation.
LittleCMS doesn't get blue tones because ICC white paper #6. It fixes such "wrong" display profiles. http://www.color.org/ICC_white_paper_6_v2_and_v4_display_profile_difference s.pdf Otherwise, with -d1 LittleCMS behaves like wcs and PhotoShop CS4. Note that in version 2 you also have incomplete state of adaptation, which you can get with -d0.5 for example. That is useful for match to screen scenario s. Regards Marti ----- Forwarded message from lo...@steelbytes.com ----- Date: Mon, 10 May 2010 16:13:09 +1000 From: Louis Solomon <lo...@steelbytes.com> Reply-To: Louis Solomon <lo...@steelbytes.com> Subject: RE: [Lcms-user] [ANNOUNCE] LittleCMS 2.0 released To: i...@littlecms.com Hi, Here's the result of my testing of LittleCMS 2.0 vs SampleICC 1.5.1 vs WindowsColorSystem (Win7) for converting spot colours in Absolute mode. The attached image is the output of each combination of the following: * two source images: [adbe98] and [pphot]. These are two tiff of the gretag 24 swatches, one with the Adobe98 RGB values, and one with ProPhoto RGB values . * tifficc.exe from littlecms 2.0 [lcms2], iccapplyprofile.exe from sampleic c 1.5.1 [sicc] and my own tool that uses the Windows Color System [wcs] (ICM with the WCS_ALWAYS flag set). * four different sRGB profiles, 'sRGB Color Space Profile.icm' [old] from Windows and sRGB_IEC61966-2-1_noBPC.icc [-BPC], sRGB_IEC61966-2-1_withBPC.i cc [+BPC] & sRGB_v4_ICC_preference.icc [v4] from www.color.org/srgbprofiles.xalter. Note that WindowsColorSystem gives a 'netural' result for the greyscale st ripe in all cases, but LittleCMS2 and SampleICC sometimes give a blue result sometimes a brown result and sometimes a neutral result. Now maybe you'll say some of those profiles are broken, or maybe not. I am just bugged that these three CMSs don't agree. (All the source files are available if you would like to repro.) Louis Solomon www.SteelBytes.com -----Original Message----- From: i...@littlecms.com [mailto:i...@littlecms.com] Sent: Sunday, 9 May 2010 2:25 AM To: lcms-user@lists.sourceforge.net Subject: [Lcms-user] [ANNOUNCE] LittleCMS 2.0 released Hi, I am pleased to the announce the release 2.0 of the LittleCMS open source c olor engine. Version 2.0 is an important milestone, among other improvements, it delivers: - Full implementation of the ICC standard - Improved documentation - Better portability - Easier extensibility Therefore, migration to 2.x branch is highly encouraged. Little CMS intends to be a small-footprint color management engine, with sp ecial focus on accuracy and performance. It uses the International Color Consorti um standard (ICC), which is the modern standard when regarding to color management. The ICC specification is widely used and is referred to in many International and other de-facto standards. For more information, please take a look on Main site: http://www.littlecms.com Downloads: http://www.littlecms.com/downloads.htm Best regards, Martà Maria The LittleCMS project http://www.littlecms.com --------------------------------------------------------------------------- --- _______________________________________________ Lcms-user mailing list Lcms-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/lcms-user ----- End forwarded message ----- ----- End forwarded message ----- ------------------------------------------------------------------------------ _______________________________________________ Lcms-user mailing list Lcms-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/lcms-user
