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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"[Bug]: DeprecationWarning from Pillow 11.3.0 about 'mode' parameter of PIL.Image.fromarray()","articleBody":"### Bug summary\n\nPillow 11.3.0 has [deprecated](https://pillow.readthedocs.io/en/stable/deprecations.html#image-fromarray-mode-parameter) the 'mode' parameter for [PIL.Image.fromarray()](https://pillow.readthedocs.io/en/stable/reference/Image.html#PIL.Image.fromarray). The DeprecationWarning causes Azure DevOps builds using matplotlib's plt.figure() to fail when `PYTHONWARNINGS=error`\n\n### Code for reproduction\nThis stacktrace is from an Azure DevOps Microsoft-hosted Windows agent ('windows-2019' VM image) using Python 3.9.13:\n\n```Python\nTraceback (most recent call last):\n\u003cour code deleted\u003e\n    self._fig = plt.figure(figsize=(9, 6))\n  File \"C:\\hostedtoolcache\\windows\\Python\\3.9.13\\x64\\lib\\site-packages\\matplotlib\\pyplot.py\", line 1027, in figure\n    manager = new_figure_manager(\n  File \"C:\\hostedtoolcache\\windows\\Python\\3.9.13\\x64\\lib\\site-packages\\matplotlib\\pyplot.py\", line 550, in new_figure_manager\n    return _get_backend_mod().new_figure_manager(*args, **kwargs)\n  File \"C:\\hostedtoolcache\\windows\\Python\\3.9.13\\x64\\lib\\site-packages\\matplotlib\\backend_bases.py\", line 3507, in new_figure_manager\n    return cls.new_figure_manager_given_figure(num, fig)\n  File \"C:\\hostedtoolcache\\windows\\Python\\3.9.13\\x64\\lib\\site-packages\\matplotlib\\backend_bases.py\", line 3512, in new_figure_manager_given_figure\n    return cls.FigureCanvas.new_manager(figure, num)\n  File \"C:\\hostedtoolcache\\windows\\Python\\3.9.13\\x64\\lib\\site-packages\\matplotlib\\backend_bases.py\", line 1797, in new_manager\n    return cls.manager_class.create_with_canvas(cls, figure, num)\n  File \"C:\\hostedtoolcache\\windows\\Python\\3.9.13\\x64\\lib\\site-packages\\matplotlib\\backends\\_backend_tk.py\", line 504, in create_with_canvas\n    manager = cls(canvas, num, window)\n  File \"C:\\hostedtoolcache\\windows\\Python\\3.9.13\\x64\\lib\\site-packages\\matplotlib\\backends\\_backend_tk.py\", line 457, in __init__\n    super().__init__(canvas, num)\n  File \"C:\\hostedtoolcache\\windows\\Python\\3.9.13\\x64\\lib\\site-packages\\matplotlib\\backend_bases.py\", line 2665, in __init__\n    tools.add_tools_to_container(self.toolbar)\n  File \"C:\\hostedtoolcache\\windows\\Python\\3.9.13\\x64\\lib\\site-packages\\matplotlib\\backend_tools.py\", line 1007, in add_tools_to_container\n    container.add_tool(tool, group, position)\n  File \"C:\\hostedtoolcache\\windows\\Python\\3.9.13\\x64\\lib\\site-packages\\matplotlib\\backend_bases.py\", line 3323, in add_tool\n    self.add_toolitem(tool.name, group, position,\n  File \"C:\\hostedtoolcache\\windows\\Python\\3.9.13\\x64\\lib\\site-packages\\matplotlib\\backends\\_backend_tk.py\", line 980, in add_toolitem\n    button = NavigationToolbar2Tk._Button(frame, name, image_file, toggle,\n  File \"C:\\hostedtoolcache\\windows\\Python\\3.9.13\\x64\\lib\\site-packages\\matplotlib\\backends\\_backend_tk.py\", line 825, in _Button\n    NavigationToolbar2Tk._set_image_for_button(self, b)\n  File \"C:\\hostedtoolcache\\windows\\Python\\3.9.13\\x64\\lib\\site-packages\\matplotlib\\backends\\_backend_tk.py\", line 767, in _set_image_for_button\n    im_alt = _recolor_icon(im, foreground)\n  File \"C:\\hostedtoolcache\\windows\\Python\\3.9.13\\x64\\lib\\site-packages\\matplotlib\\backends\\_backend_tk.py\", line 754, in _recolor_icon\n    return Image.fromarray(image_data, mode=\"RGBA\")\n  File \"C:\\hostedtoolcache\\windows\\Python\\3.9.13\\x64\\lib\\site-packages\\PIL\\Image.py\", line 3314, in fromarray\n    deprecate(\"'mode' parameter\", 13)\n  File \"C:\\hostedtoolcache\\windows\\Python\\3.9.13\\x64\\lib\\site-packages\\PIL\\_deprecate.py\", line 68, in deprecate\n    warnings.warn(\nDeprecationWarning: 'mode' parameter is deprecated and will be removed in Pillow 13 (2026-10-15)\n```\nSimilar failures occur in Linux and Windows on Pythons 3.9 and 3.12.\n\n### Actual outcome\n\n`DeprecationWarning: 'mode' parameter is deprecated and will be removed in Pillow 13 (2026-10-15)`\n\n### Expected outcome\n\nNo deprecation warning.\n\n### Additional information\n\nOur DevOps pipelines started breaking with this on 2 July when pillow (installed via pip) upgraded from 11.2.1 to 11.3.0.\n\n### Operating system\n\nWindows\n\n### Matplotlib Version\n\n3.9.4\n\n### Matplotlib Backend\n\nNot sure, TkAgg?\n\n### Python version\n\n3.9.13\n\n### Jupyter version\n\nN/A\n\n### Installation\n\npip","author":{"url":"https://github.com/cacti77","@type":"Person","name":"cacti77"},"datePublished":"2025-07-02T12:22:43.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":7},"url":"https://github.com/30249/matplotlib/issues/30249"}