cv2.imshow("image", img) cv2.error: OpenCV(4.7.0) D:\a\opencv-python\opencv-python\opencv\modules\highgui\src\window.cpp:971: error: (-215:Assertion failed) size.width>0 && size.height>0 in function 'cv::imshow'

这个错误是因为传递给cv2.imshow函数的图像大小为零。请确保图像大小不为零并且已正确加载。您可以通过检查图像大小是否大于零来验证这一点，例如：

if img.shape[0] > 0 and img.shape[1] > 0:
cv2.imshow("image", img)
else:
print("Image size is 0.")