Fix snapdiff ae method.
diff --git a/scripts/snapdiff.py b/scripts/snapdiff.py
index 13e5069..9253d16 100755
--- a/scripts/snapdiff.py
+++ b/scripts/snapdiff.py
@@ -87,7 +87,7 @@
         bits = -math.log(rel_error)/math.log(2.0)
         return bits
 
-    def ae(self):
+    def ae(self, fuzz = 0.05):
         # Compute absolute error
         # TODO: this is approximate due to the grayscale conversion
         h = self.diff.convert('L').histogram()