> Hi, > > while brightening HDRs I see often the coloured halos arround the sun, > clouds and other bright regions. I understand that an simple clipping > of one channel befor the maximum of all other channels is reached > causes such hue shifts. Only I thought lcms is able to do an hue > preserving clip. > > What options I need to enable? Input is floating point numbers with > values over 1.0.
Basically the limitation is already the data format of ICC profiles. Neither the 1D TRC tables of matrix/shaper nor the input table of CLUT tables can accept device input values > 1.0 (i.e. actually 255 or 65535), since the tables are directly indexed by the device values, and by definition the last enty in the table corresponds to the max. device value (i.e. 1.0 or 255 or 65535 - however you normalize it), thus there do not exist table entries beyond this value. Only for Matrix/Gamma profiles (or matrix + parametric curve) the CMM could theoretically convert RGB > 1.0 to corresponding XYZ values (e.g. with Y > 1.0), but I'm not sure if LCMS does. Marti? -Gerhard > regards > Kai-Uwe -- Superg�nstige DSL-Tarife + WLAN-Router f�r 0,- EUR* Jetzt zu GMX wechseln und sparen http://www.gmx.net/de/go/dsl ------------------------------------------------------- This SF.Net email is sponsored by: YOU BE THE JUDGE. Be one of 170 Project Admins to receive an Apple iPod Mini FREE for your judgement on who ports your project to Linux PPC the best. Sponsored by IBM. Deadline: Sept. 13. Go here: http://sf.net/ppc_contest.php _______________________________________________ Lcms-user mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/lcms-user
