...

diff --git a/MagickCore/quantize.c b/MagickCore/quantize.c
index 32b6a98a85f450eaba1a62692112f357c6d07630..d39ec08213ccd05ec8636853908c1eb8680fad42 100644 (file)
--- a/MagickCore/quantize.c
+++ b/MagickCore/quantize.c
@@ -1140,8 +1140,11 @@ static void ClosestColor(const Image *image,CubeInfo *cube_info,
               distance+=pixel*pixel;
               if (distance <= cube_info->distance)
                 {
-                  pixel=p->alpha-q->alpha;
-                  distance+=pixel*pixel;
+                  if (cube_info->associate_alpha != MagickFalse)
+                    {
+                      pixel=p->alpha-q->alpha;
+                      distance+=pixel*pixel;
+                    }
                   if (distance <= cube_info->distance)
                     {
                       cube_info->distance=distance;