From: cristy <urban-warrior@git.imagemagick.org>
Date: Fri, 16 Apr 2010 14:47:22 +0000 (+0000)
Subject: (no commit message)
X-Git-Tag: 7.0.1-0~9640
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=4846bb6a5f8535975997caa78c337500fa66dd57;p=imagemagick

---

diff --git a/magick/colorspace.c b/magick/colorspace.c
index 134c9516d..3039cc643 100644
--- a/magick/colorspace.c
+++ b/magick/colorspace.c
@@ -1253,19 +1253,22 @@ static inline void ConvertLabToXYZ(const double L,const double a,const double b,
   assert(X != (double *) NULL);
   assert(Y != (double *) NULL);
   assert(Z != (double *) NULL);
-  y=((2.0*L-1.0)+0.160)/1.160;
-  x=(2.0*a-1.0)/5.000+y;
-  z=y-(2.0*b-1.0)/2.000;
-  if ((x*x*x) > (216.0/24389.0))
-    x=x*x*x;
-  else
-    x=(x-16.0/116.0)/7.787;
-  if ((y*y*y) > (216.0/24389.0))
-    y=y*y*y;
+  y=(100.0*L+16.0)/116.0;
+  x=255.0*(a > 0.5 ? a-1.0 : a)/500.0+y;
+  z=y-255.0*(b > 0.5 ? b-1.0 : b)/200.0;
+  cube=y*y*y;
+  if (cube > 0.008856)
+    y=cube;
   else
     y=(y-16.0/116.0)/7.787;
-  if ((z*z*z) > (216.0/24389.0))
-    z=z*z*z;
+  cube=x*x*x;
+  if (cube > 0.008856)
+    x=cube;
+  else
+    x=(x-16.0/116.0)/7.787;
+  cube=z*z*z;
+  if (cube > 0.008856)
+    z=cube;
   else
     z=(z-16.0/116.0)/7.787;
   *X=0.9504559271*x;
@@ -1299,6 +1302,18 @@ static inline void ConvertXYZToRGB(const double x,const double y,const double z,
   r=3.2407100*x-1.5372600*y-0.4985710*z;
   g=(-0.9692580*x+1.8759900*y+0.0415557*z);
   b=0.0556352*x-0.2039960*y+1.0570700*z;
+  if (r > 0.0031308)
+    r=1.055*pow(r,1.0/2.4)-0.055;
+  else
+    r*=12.92;
+  if (g > 0.0031308)
+    g=1.055*pow(g,1.0/2.4)-0.055;
+  else
+    g*=12.92;
+  if (b > 0.0031308)
+    b=1.055*pow(b,1.0/2.4)-0.055;
+  else
+    b*=12.92;
   *red=ClampToQuantum((MagickRealType) QuantumRange*r);
   *green=ClampToQuantum((MagickRealType) QuantumRange*g);
   *blue=ClampToQuantum((MagickRealType) QuantumRange*b);