Turn off alpha channel for the compare difference image

diff --git a/ChangeLog b/ChangeLog
index 8589ca02e3751ea98e618a0ff1765b5d93bdf2d3..9e670839bfb1f8354d354d6468bc81b355c2d76d 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -5,6 +5,8 @@
   * Fix small memory leak (patch provided by Андрей Черный).
   * Coder path traversal is not authorized (bug report provided by
     Masaaki Chida).
+  * Turn off alpha channel for the compare difference image (reference
+    http://www.imagemagick.org/discourse-server/viewtopic.php?f=3&t=29828).
 
 2016-05-31  7.0.1-8 Cristy  <quetzlzacatenango@image...>
   * Release ImageMagick version 7.0.1-8, GIT revision 18334:97775b5:20160531.

diff --git a/MagickCore/compare.c b/MagickCore/compare.c
index 1c4ebf83f2b9db444f23f11462d78a77ee4cfff8..c78a47bc94f3ef4d51f1cbe0c74d327059bdc05c 100644 (file)
--- a/MagickCore/compare.c
+++ b/MagickCore/compare.c
@@ -302,6 +302,7 @@ MagickExport Image *CompareImages(Image *image,const Image *reconstruct_image,
   image_view=DestroyCacheView(image_view);
   (void) CompositeImage(difference_image,highlight_image,image->compose,
     MagickTrue,0,0,exception);
+  (void) SetImageAlphaChannel(difference_image,OffAlphaChannel,exception);
   highlight_image=DestroyImage(highlight_image);
   if (status == MagickFalse)
     difference_image=DestroyImage(difference_image);