Fix for division by zero.

diff --git a/MagickCore/colormap.c b/MagickCore/colormap.c
index e7cf95d4b1ccd11ed588cb4a149d333fd3e1337e..4897d18aa47fdffa50efc5957cfe87b12206a41f 100644 (file)
--- a/MagickCore/colormap.c
+++ b/MagickCore/colormap.c
@@ -133,7 +133,7 @@ MagickExport MagickBooleanType AcquireImageColormap(Image *image,
     double
       pixel;
 
-    pixel=(double) (i*(QuantumRange/(image->colors-1)));
+    pixel=(double) (i*(QuantumRange/MagickMax(colors-1,1)));
     GetPixelInfo(image,image->colormap+i);
     image->colormap[i].alpha_trait=BlendPixelTrait;
     image->colormap[i].red=pixel;