Python OpenCV将所有黑色像素更改为白色

向右看齐 2023-10-01 16:03 9阅读 0赞

我是 OpenCV 的新手，我不明白如何遍历和更改所有颜色代码`RGB(0,0,0)`为白色的黑色像素`RGB(255,255,255)`。是否有任何功能或方法来检查所有像素以及是否`RGB(0,0,0)`使其成为`RGB(255,255,255)`.

假设您的图像表示为一个`numpy`形状数组`(height, width, channels)`（`cv2.imread`返回什么），您可以执行以下操作：

height, width, _ = img.shape
    
    for i in range(height):
        for j in range(width):
            # img[i,j] is the RGB pixel at position (i, j)
            # check if it's [0, 0, 0] and replace with [255, 255, 255] if so
            if img[i,j].sum() == 0:
                img[i, j] = [255, 255, 255]

一种更快的基于掩码的方法如下所示：

# get (i, j) positions of all RGB pixels that are black (i.e. [0, 0, 0])
    black_pixels = np.where(
        (img[:, :, 0] == 0) & 
        (img[:, :, 1] == 0) & 
        (img[:, :, 2] == 0)
    )
    
    # set those pixels to white
    img[black_pixels] = [255, 255, 255]

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[watermark_type_d3F5LXplbmhlaQ_shadow_50_text_Q1NETiBAYWxsd2F5Mg_size_16_color_FFFFFF_t_70_g_se_x_16 1]: https://img-blog.csdnimg.cn/23d6660724714550ab8d0a4fcc0b3e15.png?x-oss-process=image/watermark,type_d3F5LXplbmhlaQ,shadow_50,text_Q1NETiBAYWxsd2F5Mg==,size_16,color_FFFFFF,t_70,g_se,x_16