Hi Elle,
I've tried RedHat 6 with gcc 4.4.7 and a old Mac PowerPC running darwin9 4.0.1, in both cases I got no issues, and the return values were the expected ones. I wonder how you do to get this particular result: > transicc -c0 -t1 -w -o sRGB-V2-g10.icc -i sRGB-V4-g20.icc > > 255 255 0 > R=255.0000 G=255.0000 B=0.0134 (the B channel should be zero) > > 255 0 0 > R=255.0000 G=0.0282 B=0.0000 (the G channel should be zero) > > 255 0 255 > R=255.0000 G=0.0331 B=255.0000 (the G channel should be zero) > > 255 0.001 0.001 > R=255.0000 G=0.5037 B=0.5051 (G and B should be equal to each other) As said I cannot reproduce this 0.0134, 0.0282 and 0.5037. In all my tests I got zero, either on positive or negative side. Maybe you used a different profiles? Could you check the profiles you sent? Otherwise, regarding the fact gimp does not like the negative numbers, the obvious fixup is to run a filter on the buffers removing the values the app does not like. This cannot be done at CMM level because there are other apps that do use such values. A simple for loop and a couple of if statements to clamp between 0 and 1.0 woudl solve the issue. Regards Marti Quoting marti.ma...@littlecms.com: > Hi Elle, > > Thanks for reporting. I was using VS2012 and VS2013 under win7. Next > monday will try some linux and mac. If platforms differ, then this may > be a nasty issue. > > > Regards > Marti. > > Quoting Elle Stone <ellest...@ninedegreesbelow.com>: > >> On 09/11/2014 06:32 PM, marti.ma...@littlecms.com wrote: >>> >>> >>> Hi Elle, >>> >>> Sorry, with the profiles you sent and transicc from lcms2-2.6, this does >>> not happen. I got the expected values. >>> Please check the version of lcms2 you are using. >>> >>> BTW, -c0 is not needed in lcms2 and may cause problems. This may be the >>> source of the issue in versions previous to 2.6 >>> >>> M:\lcms2-2.6\bin>transicc -c0 -t1 -w -o sRGB-V2-g10.icc -i sRGB-V4-g20.icc >>> LittleCMS ColorSpace conversion calculator - 4.2 [LittleCMS 2.06] >>> >>> Enter values, 'q' to quit >>> R? 255 >>> G? 0 >>> B? 0 >>> >>> R=255.0000 G=0.0000 B=-0.0000 >>> >>> Enter values, 'q' to quit >>> R? 255 >>> G? 255 >>> B? 0 >>> >>> R=255.0000 G=255.0000 B=0.0000 >>> >>> Enter values, 'q' to quit >>> >>> >> >> Hi Marti, >> >> Thanks! for checking. I tried with and without "-c0", running LCMS2 >> versions 2.5, 2.6 and from git on my 64-bit Gentoo box. I also >> checked on a 32-bit OpenSuse machine and a 32-bit Arch Linux >> machine. Results were identical in all cases. The near-zero and zero >> channel values aren't converting correctly. >> >> Could our different results be from running different platforms? I >> don't have access to an Apple or Windows machine. >> >> As a check I tried converting a 16-bit tiff with a gradient running >> from red to black, zero in the green and blue channels, from linear >> gamma to gamma=2.0 versions of sRGB, using cctiff, tifficc, and >> tificc. >> >> Upon opening the converted tiffs with GIMP from git and color >> picking across the gradients, the cctiff and tifficc gradients were >> still zero in the green and blue channels, all across the gradient. >> But the tificc version had green channel values between 0 and 10, >> and blue channel values between 0 and 3, flipping randomly as the >> red channel value changed (not proportional to the red channel value). >> >> Elle > > > > ------------------------------------------------------------------------------ > Want excitement? > Manually upgrade your production database. > When you want reliability, choose Perforce > Perforce version control. Predictably reliable. > http://pubads.g.doubleclick.net/gampad/clk?id=157508191&iu=/4140/ostg.clktrk > _______________________________________________ > Lcms-user mailing list > Lcms-user@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/lcms-user ------------------------------------------------------------------------------ Want excitement? Manually upgrade your production database. When you want reliability, choose Perforce Perforce version control. Predictably reliable. http://pubads.g.doubleclick.net/gampad/clk?id=157508191&iu=/4140/ostg.clktrk _______________________________________________ Lcms-user mailing list Lcms-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/lcms-user
