Udi Fuchs píše v Čt 25. 02. 2010 v 11:23 -0600: > of the second gamma curve. What we want is to have a linear input > profile. It is a simple 3x3 matrix profile and it almost works, except > for the haze issue. > Udi,
Martin is actually saying the opposite: from the view-point of image quality it is better if we profile images, which are already encoded with perceptually linear luminance (gamma 2.2 being the close match). Then, CMS "only" transforms pixels between differently sized gamuts (from camera profile to working space or monitor/printer profile) and possibly adjusts for white point, but does not have to do any major gamma transcoding. > lprof can create profiles that handle 16-bit linear input, so we know > that LCMS can handle it. Yes, LCMS can do the gamma transform from digitally linear CameraRGB to sRGB/AdobeRGB/MyMonitorRGB/MyPrinterRGB (all with gamma close to 2.2) on the fly as part of colour transform, but the results are supposed to be inferior. Also, the Adobe Color Matrix and many vendors camera profiles expect the image data being already encoded at 1/2.2 gamma (hence the slider in UFRaw). So, these are not digitally linear input profiles. Regards, Milan Knizek knizek (dot) confy (at) volny (dot) cz http://www.milan-knizek.net - About linux and photography (Czech language only) ------------------------------------------------------------------------------ Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev _______________________________________________ ufraw-devel mailing list ufraw-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/ufraw-devel
