ConvertYDbDrToRGB 1900 magick/colorspace.c               ConvertYDbDrToRGB(X,Y,Z,&red,&green,&blue);
ConvertYDbDrToRGB  734 tests/validate.c   ConvertYDbDrToRGB(0.783460,-0.480932+0.5,0.451670+0.5,&r,&g,&b);