Let dpi be set when saving JPEG using Agg backend

dstansby · dstansby · commit 8fd849d60440 · 2017-08-21T20:42:52.000+01:00
diff --git a/lib/matplotlib/backends/backend_agg.py b/lib/matplotlib/backends/backend_agg.py
@@ -568,10 +568,12 @@ def print_jpg(self, filename_or_obj, *args, **kwargs):
             background = Image.new('RGB', size, color)
             background.paste(image, image)
             options = restrict_dict(kwargs, ['quality', 'optimize',
-                                             'progressive'])
+                                             'progressive', 'dpi'])
 
             if 'quality' not in options:
                 options['quality'] = rcParams['savefig.jpeg_quality']
+            # Set the same dpi in both x and y directions
+            options['dpi'] = (options['dpi'], options['dpi'])
 
             return background.save(filename_or_obj, format='jpeg', **options)
         print_jpeg = print_jpg
