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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"PillowWriter GIF duration and loop","articleBody":"\u003c!--\r\nWelcome! Thanks for thinking of a way to improve Matplotlib.\r\n\r\n\r\nBefore creating a new feature request please search the issues for relevant feature requests.\r\n--\u003e\r\n\r\n### Current PillowWriter functionality does not allow me to specify the duration for each of the gif frames and it is not possible to not have the gif loop.\r\nAdditionally, I frequently get a **ValueError: buffer is not large enough** when animating multi axes figures. (Not sure if this is a common problem).\r\n\r\nAnimation to help introduce a visual story can be quite beneficial to understanding and for that I would like to be able to not loop the gif and \"pause\" the gif via different durations for all frames.\r\n\r\n\u003c!--\r\nProvide a clear and concise description of the problem this feature will solve. \r\n\r\nFor example:\r\n* I'm always frustrated when [...] because [...]\r\n* I would like it if [...] happened when I [...] because [...]\r\n* Here is a sample image of what I am asking for [...]\r\n--\u003e\r\n\r\n### Proposed Solution\r\n\r\n1) add duration=None, loop=0 arguments to setup() and to a PillowWriter specific saving context_manager.\r\nTo not loop we can specify loop=None and then we specifically need to not pass the loop argument to save() in finish().\r\n\r\n2) What is the difference between Image.frombuffer and Image.open(buf)? I find that Image.open(buf) solves my problem of the ValueError: buffer is not large enough.\r\nIt seems to take more time for me though. (about +33%)\r\n\r\n3) removed unused variable assignment: renderer = self.fig.canvas.get_renderer() from grab_frame()\r\n\r\n```\r\nclass PillowWriter(AbstractMovieWriter):\r\n    @classmethod\r\n    def isAvailable(cls):\r\n        return True\r\n\r\n    def setup(self, fig, outfile, dpi=None, duration=None, loop=None):\r\n        super().setup(fig, outfile, dpi=dpi)\r\n        self.duration = duration\r\n        self.loop = loop\r\n        self._frames = []\r\n\r\n    def grab_frame(self, **savefig_kwargs):\r\n        buf = BytesIO()\r\n        self.fig.savefig(\r\n            buf, **{**savefig_kwargs, \"dpi\": self.dpi})\r\n        self._frames.append(Image.open(buf))\r\n\r\n    def finish(self):\r\n        duration = self.duration or int(1000 / self.fps)\r\n\r\n        # to not loop at all we need to avoid passing the loop argument to save\r\n        if self.loop is None:\r\n            self._frames[0].save(\r\n                self.outfile, save_all=True, append_images=self._frames[1:],\r\n                duration=duration)\r\n        else:\r\n            self._frames[0].save(\r\n                self.outfile, save_all=True, append_images=self._frames[1:],\r\n                duration=duration, loop=self.loop)\r\n\r\n    @contextlib.contextmanager\r\n    def saving(self, fig, outfile, dpi, duration=None, loop=0, *args, **kwargs):\r\n        \"\"\"\r\n        Context manager to facilitate writing the movie file.\r\n        ``*args, **kw`` are any parameters that should be passed to `setup`.\r\n        \"\"\"\r\n        # This particular sequence is what contextlib.contextmanager wants\r\n        self.setup(fig, outfile, dpi, duration, loop, *args, **kwargs)\r\n        try:\r\n            yield self\r\n        finally:\r\n            self.finish()\r\n```\r\n\r\n\r\n### Additional context and prior art\r\n\r\nendless looping for gifs was introduced here:\r\nhttps://github.com/matplotlib/matplotlib/pull/11789\r\n\r\nDocumentation would have to be updated I suppose.\r\nIf this seems like a useful improvement to the PillowWriter I could go ahead and create a PR.","author":{"url":"https://github.com/znstrider","@type":"Person","name":"znstrider"},"datePublished":"2020-12-23T14:23:14.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":9},"url":"https://github.com/19169/matplotlib/issues/19169"}