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      "source": [
        "\n# Convert texts to images\n"
      ]
    },
    {
      "cell_type": "code",
      "execution_count": null,
      "metadata": {
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      },
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      "source": [
        "from io import BytesIO\n\nimport matplotlib.pyplot as plt\n\nfrom matplotlib.figure import Figure\nfrom matplotlib.transforms import IdentityTransform\n\n\ndef text_to_rgba(s, *, dpi, **kwargs):\n    # To convert a text string to an image, we can:\n    # - draw it on an empty and transparent figure;\n    # - save the figure to a temporary buffer using ``bbox_inches=\"tight\",\n    #   pad_inches=0`` which will pick the correct area to save;\n    # - load the buffer using ``plt.imread``.\n    #\n    # (If desired, one can also directly save the image to the filesystem.)\n    fig = Figure(facecolor=\"none\")\n    fig.text(0, 0, s, **kwargs)\n    with BytesIO() as buf:\n        fig.savefig(buf, dpi=dpi, format=\"png\", bbox_inches=\"tight\",\n                    pad_inches=0)\n        buf.seek(0)\n        rgba = plt.imread(buf)\n    return rgba\n\n\nfig = plt.figure()\nrgba1 = text_to_rgba(r\"IQ: $\\sigma_i=15$\", color=\"blue\", fontsize=20, dpi=200)\nrgba2 = text_to_rgba(r\"some other string\", color=\"red\", fontsize=20, dpi=200)\n# One can then draw such text images to a Figure using `.Figure.figimage`.\nfig.figimage(rgba1, 100, 50)\nfig.figimage(rgba2, 100, 150)\n\n# One can also directly draw texts to a figure with positioning\n# in pixel coordinates by using `.Figure.text` together with\n# `.transforms.IdentityTransform`.\nfig.text(100, 250, r\"IQ: $\\sigma_i=15$\", color=\"blue\", fontsize=20,\n         transform=IdentityTransform())\nfig.text(100, 350, r\"some other string\", color=\"red\", fontsize=20,\n         transform=IdentityTransform())\n\nplt.show()"
      ]
    },
    {
      "cell_type": "markdown",
      "metadata": {},
      "source": [
        ".. admonition:: References\n\n   The use of the following functions, methods, classes and modules is shown\n   in this example:\n\n   - `matplotlib.figure.Figure.figimage`\n   - `matplotlib.figure.Figure.text`\n   - `matplotlib.transforms.IdentityTransform`\n   - `matplotlib.image.imread`\n\n"
      ]
    }
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