Allow Animation.save() to accept keyword arguments which are passed on to savefig() when saving individual frames. This can be used to set tight bounding boxes etc.

maxalbert · maxalbert · commit 9a48efd733f7 · 2012-10-31T22:18:12.000Z
diff --git a/lib/matplotlib/animation.py b/lib/matplotlib/animation.py
@@ -184,17 +184,19 @@ def finish(self):
         'Finish any processing for writing the movie.'
         self.cleanup()
 
-    def grab_frame(self):
+    def grab_frame(self, **savefig_kwargs):
         '''
         Grab the image information from the figure and save as a movie frame.
+        All keyword arguments in savefig_kwargs are passed on to the 'savefig'
+        command that saves the figure.
         '''
         verbose.report('MovieWriter.grab_frame: Grabbing frame.',
                        level='debug')
         try:
             # Tell the figure to save its data to the sink, using the
             # frame format and dpi.
             self.fig.savefig(self._frame_sink(), format=self.frame_format,
-                dpi=self.dpi)
+                dpi=self.dpi, **savefig_kwargs)
         except RuntimeError:
             out, err = self._proc.communicate()
             verbose.report('MovieWriter -- Error running proc:\n%s\n%s' % (out,
@@ -545,7 +547,8 @@ def _stop(self, *args):
         self.event_source = None
 
     def save(self, filename, writer=None, fps=None, dpi=None, codec=None,
-             bitrate=None, extra_args=None, metadata=None, extra_anim=None):
+             bitrate=None, extra_args=None, metadata=None, extra_anim=None,
+             savefig_kwargs={}):
         '''
         Saves a movie file by drawing every frame.
 
@@ -586,6 +589,11 @@ def save(self, filename, writer=None, fps=None, dpi=None, codec=None,
         `matplotlib.Figure` instance. Also, animation frames will just be
         simply combined, so there should be a 1:1 correspondence between
         the frames from the different animations.
+
+        *savefig_kwargs* is a dictionary containing keyword arguments to be
+        passed on to the 'savefig' command which is called repeatedly to save
+        the individual frames. This can be used to set tight bounding boxes,
+        for example.
         '''
         # Need to disconnect the first draw callback, since we'll be doing
         # draws. Otherwise, we'll end up starting the animation.
@@ -645,7 +653,7 @@ def save(self, filename, writer=None, fps=None, dpi=None, codec=None,
                 for anim, d in zip(all_anim, data):
                     #TODO: Need to see if turning off blit is really necessary
                     anim._draw_next_frame(d, blit=False)
-                writer.grab_frame()
+                writer.grab_frame(**savefig_kwargs)
 
         # Reconnect signal for first draw if necessary
         if reconnect_first_draw:
