FIX: normalize image data in wring_png fast path

tacaswell · tacaswell · commit 6280da8f2a81 · 2016-11-01T14:20:39.000-04:00
Closes #7373
diff --git a/lib/matplotlib/image.py b/lib/matplotlib/image.py
@@ -524,7 +524,7 @@ def contains(self, mouseevent):
 
     def write_png(self, fname):
         """Write the image to png file with fname"""
-        im = self.to_rgba(self._A, bytes=True, norm=False)
+        im = self.to_rgba(self._A, bytes=True, norm=True)
         _png.write_png(im, fname)
 
     def set_data(self, A):
