Make ImageMagick multi-image size calculations work for .ico files

* src/image.c (imagemagick_load_image): Compute image sizes
correctly in multi-image .ico files and the like (bug#18333).

1 files changed, 21 insertions, 5 deletions

diff --git a/src/image.c b/src/image.c
index 06a8154842c..7cf1bc4c362 100644
--- a/src/image.c
+++ b/src/image.c
@@ -8896,12 +8896,28 @@ imagemagick_load_image (struct frame *f, struct image *img,
      "super-wand". */
   if (MagickGetNumberImages (image_wand) > 1)
     {
-      MagickWand *super_wand = image_wand;
-      image_wand = imagemagick_compute_animated_image (super_wand, ino);
-      if (! image_wand)
-        image_wand = super_wand;
+      /* This is an animated image (it has a delay), so compute the
+         composite image etc. */
+      if (MagickGetImageDelay (image_wand) > 0)
+        {
+          MagickWand *super_wand = image_wand;
+          image_wand = imagemagick_compute_animated_image (super_wand, ino);
+          if (! image_wand)
+            image_wand = super_wand;
+          else
+            DestroyMagickWand (super_wand);
+        }
       else
-        DestroyMagickWand (super_wand);
+        /* This is not an animated image: It's just a multi-image file
+           (like an .ico file).  Just return the correct
+           sub-image.  */
+        {
+          MagickWand *super_wand = image_wand;
+
+          MagickSetIteratorIndex (super_wand, ino);
+          image_wand = MagickGetImage (super_wand);
+          DestroyMagickWand (super_wand);
+        }
     }
 
   /* Retrieve the frame's background color, for use later.  */