python 错误: tuples indices must be integers or slices not tuples

Question

我正在尝试使用 cv2 在图像中显示矩形。但是由于以下错误，我无法在图像上制作它们。

我已将图像转换为 numpy 数组并尝试以不同方式写下顶点，但一般格式是正确的。我不知道从哪里出现元组错误。

def draw_rect(img, dims, color = None):
    img = img.copy()
    dims = dims.reshape(-1, 4)
    if not color:
        color = (255, 255, 255)  #rgb values for white color

    for dim in dims:

        x, y = (dim[0], dim[1]) , (dim[2], dim[3])

        x = int(x[0]), int(x[1])
        y = int(y[0]), int(y[1])
        img = cv2.rectangle(img, x, y, color, int(max(img.shape[:,2])/200))  # error
    return img
def main():
    addr = 'test1_sec0.jpg'
    bbox = 'test1_sec0.jpg.csv'
    img_show(addr)  # used to read and show the image using cv2. Works fine.
    dims = bbox_read(bbox)  # used to read the boundary boxes. Works fine
    img = cv2.imread(addr, 1)
    img_data = np.asarray(img, dtype = 'int32') 
    print(img_data)
    plt.imshow(draw_rect(img_data, dims))  # error
    plt.show( )


if __name__ == '__main__':
    main()

'

 Traceback (most recent call last):
      File "ImgAug.py", line 56, in <module>
        main()
      File "ImgAug.py", line 51, in main
        plt.imshow(draw_rect(img_data, dims))
      File "ImgAug.py", line 41, in draw_rect
        img = cv2.rectangle(img, x[0], x[1], y[0], y[1], color, int(max(img.shape[:,2])/200))  # first argument & variable must be same cause same image should have all the bbox
    TypeError: tuple indices must be integers or slices, not tuple

Answer 1

img.shape 是一个元组，但是 img.shape[:,2] 试图用另一个元组索引它，这是无效的:

>>> class X:
...     def __getitem__(self, index):
...         print(f'The index is: {index}')
...         
>>> X()[:,2]
The index is: (slice(None, None, None), 2)

如您所见，something[:,2] 实际上生成了一个元组作为索引。