snapdiff: Avoid problems when there is a size mismatch.

1 files changed, 3 insertions, 0 deletions

diff --git a/scripts/snapdiff.py b/scripts/snapdiff.py
index aa65f51c..59ec870e 100755
--- a/scripts/snapdiff.py
+++ b/scripts/snapdiff.py
@@ -71,6 +71,9 @@ class Comparer:
         return self.ref_im.size != self.src_im.size
 
     def write_diff(self, diff_image, fuzz = 0.05):
+        if self.size_mismatch():
+            return
+
         # make a difference image similar to ImageMagick's compare utility
         mask = ImageEnhance.Brightness(self.diff).enhance(1.0/fuzz)
         mask = mask.convert('L')