René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Error at save animation with pillow","articleBody":"\u003c!--To help us understand and resolve your issue, please fill out the form to the best of your ability.--\u003e\r\n\u003c!--You can feel free to delete the sections that do not apply.--\u003e\r\n\r\n### Bug report\r\n\r\n**Bug summary**\r\n\r\n\u003c!--A short 1-2 sentences that succinctly describes the bug--\u003e\r\nline 575 of `animation.py` use `Image.frombytes` to load a `BytesIO`, this will lead to an exception -- `not enough image data`.  \r\nseems we can't feed bytes of `.png` to `frombytes` from the first question-comment of [this SO question](https://stackoverflow.com/questions/32908639/open-pil-image-from-byte-file)\r\n\r\n\r\n\r\n**Code for reproduction**\r\n\r\n\u003c!--A minimum code snippet required to reproduce the bug.\r\nPlease make sure to minimize the number of dependencies required, and provide\r\nany necessary plotted data.\r\nAvoid using threads, as Matplotlib is (explicitly) not thread-safe.--\u003e\r\n\r\n\r\n```python\r\nimport numpy as np\r\nfrom matplotlib import animation\r\nimport matplotlib.pyplot as plt\r\nfrom mpl_toolkits.mplot3d import Axes3D\r\n\r\nemb = np.random.random_sample((1000,3))\r\n\r\nfig = plt.figure(\"bug_report\")\r\nax = Axes3D(fig)\r\nax.set_xlabel('x')\r\nax.set_ylabel('y')\r\nax.set_zlabel('z')\r\nax.set_xlim3d(left=-1,right=1)\r\nax.set_ylim3d(bottom=-1,top=1)\r\nax.set_zlim3d(bottom=-1,top=1)\r\n\r\nbatch=50\r\ndef animate(i):\r\n    emb_part = emb[i*batch:(i+1)*batch]\r\n    ax.scatter(xs=emb_part[:, 0], ys=emb_part[:, 1], zs=emb_part[:, 2])\r\n    return ax\r\n\r\nani = animation.FuncAnimation(fig=fig, func=animate, frames=len(emb)//batch + 1, interval=0.01*1000, blit=False, repeat=False)\r\n\r\nani.save(\"/Users/zac/Downloads/ani.gif\", fps=30, writer='pillow')\r\n```\r\n\r\n**Actual outcome**\r\n\r\n\u003c!--The output produced by the above code, which may be a screenshot, console output, etc.--\u003e\r\n\r\n```\r\n# ....\r\nValueError: not enough image data\r\n\r\nDuring handling of the above exception, another exception occurred:\r\n# ....\r\n```\r\nactually, if we use `plt.show()` before `ani.save`, this exception wont appear, but we will get only some last parts of the animation, [example as this](https://raw.githubusercontent.com/Zachary4biz/Tahiti_any_data/master/pics/err_ani.gif)\r\n\r\n**Expected outcome**\r\n\r\n\u003c!--A description of the expected outcome from the code snippet--\u003e\r\n\u003c!--If this used to work in an earlier version of Matplotlib, please note the version it used to work on--\u003e\r\nnormally saved gif pic\r\n[example as this](https://raw.githubusercontent.com/Zachary4biz/Tahiti_any_data/master/pics/normal_ani.gif)\r\n\r\n**Matplotlib version**\r\n\u003c!--Please specify your platform and versions of the relevant libraries you are using:--\u003e\r\n  * Operating system: MacOSX\r\n  * Matplotlib version: 3.0.3\r\n  * Matplotlib backend (`print(matplotlib.get_backend())`): Qt5Agg\r\n  * Python version: 3.7.3\r\n  * Jupyter version (if applicable):\r\n  * Other libraries: numpy\r\n\r\n\u003c!--Please tell us how you installed matplotlib and python e.g., from source, pip, conda--\u003e\r\n\u003c!--If you installed from conda, please specify which channel you used if not the default--\u003e\r\n\r\n","author":{"url":"https://github.com/Zachary4biz","@type":"Person","name":"Zachary4biz"},"datePublished":"2019-11-12T04:50:09.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":14},"url":"https://github.com/15678/matplotlib/issues/15678"}