matplotlib figure转为numpy array或者PIL图像进行显示

待我称王封你为后i 2023-07-03 08:25 9阅读 0赞

# matplotlib figure转为numpy array或者PIL图像进行显示 #

实现将matplotlib绘制的图像转换为numpy数组,并使用PIL或者OpenCV进行显示

参考资料:[http://www.icare.univ-lille1.fr/tutorials/convert\_a\_matplotlib\_figure][http_www.icare.univ-lille1.fr_tutorials_convert_a_matplotlib_figure]

# -*- coding: utf-8 -*-
    """
    # --------------------------------------------------------
    # @Author : panjq
    # @E-mail : pan_jinquan@163.com
    # @Date   : 2020-02-05 11:01:49
    # --------------------------------------------------------
    """
    
    import matplotlib.pyplot as plt
    import numpy as np
    import cv2
    
    
    def fig2data(fig):
        """
        fig = plt.figure()
        image = fig2data(fig)
        @brief Convert a Matplotlib figure to a 4D numpy array with RGBA channels and return it
        @param fig a matplotlib figure
        @return a numpy 3D array of RGBA values
        """
        import PIL.Image as Image
        # draw the renderer
        fig.canvas.draw()
    
        # Get the RGBA buffer from the figure
        w, h = fig.canvas.get_width_height()
        buf = np.fromstring(fig.canvas.tostring_argb(), dtype=np.uint8)
        buf.shape = (w, h, 4)
    
        # canvas.tostring_argb give pixmap in ARGB mode. Roll the ALPHA channel to have it in RGBA mode
        buf = np.roll(buf, 3, axis=2)
        image = Image.frombytes("RGBA", (w, h), buf.tostring())
        image = np.asarray(image)
        return image
    
    
    if __name__ == "__main__":
        # Generate a figure with matplotlib</font>
        figure = plt.figure()
        plot = figure.add_subplot(111)
    
        # draw a cardinal sine plot
        x = np.arange(1, 100, 0.1)
        y = np.sin(x) / x
        plot.plot(x, y)
        plt.show()
        ##
        image = fig2data(figure)
        cv2.imshow("image", image)
        cv2.waitKey(0)

如果在Pycharm中运行出现"[AttributeError: 'FigureCanvasInterAgg' object has no attribute 'renderer'][AttributeError_ _FigureCanvasInterAgg_ object has no attribute _renderer]" 的错误,请参考修改:

[https://stackoverflow.com/questions/51214140/attributeerror-figurecanvasinteragg-object-has-no-attribute-renderer][AttributeError_ _FigureCanvasInterAgg_ object has no attribute _renderer]解决

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9wYW5qaW5xdWFuLmJsb2cuY3Nkbi5uZXQ_size_16_color_FFFFFF_t_70][]

[http_www.icare.univ-lille1.fr_tutorials_convert_a_matplotlib_figure]: http://www.icare.univ-lille1.fr/tutorials/convert_a_matplotlib_figure
[AttributeError_ _FigureCanvasInterAgg_ object has no attribute _renderer]: https://stackoverflow.com/questions/51214140/attributeerror-figurecanvasinteragg-object-has-no-attribute-renderer
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9wYW5qaW5xdWFuLmJsb2cuY3Nkbi5uZXQ_size_16_color_FFFFFF_t_70]: https://img-blog.csdnimg.cn/20200205110809763.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9wYW5qaW5xdWFuLmJsb2cuY3Nkbi5uZXQ=,size_16,color_FFFFFF,t_70