python - 使用 cv2.imread : " returned NULL without setting an error", 好像打不开图片或者获取数据

Question

这是我的代码中出现问题的部分。它应该计算图片中绿色像素的数量:

img = Image.open('path.tif')

BLACK_MIN = np.array([0, 20, 20], np.uint8)

BLACK_MAX = np.array([120, 255, 255], np.uint8)

imgg = cv2.imread(img, 1)

dst = cv2.inRange(imgg, BLACK_MIN, BLACK_MAX)

no_black = cv2.countNonZero(dst)

print('The number of black pixels is: ' + str(no_black))

Answer 1

您正在将 PIL 图像传递给 imread 但它需要一个文件路径 ( https://docs.opencv.org/2.4/modules/highgui/doc/reading_and_writing_images_and_video.html?highlight=imread#Mat%20imread(const%20string&%20filename,%20int%20flags)

你应该使用:

imgg = cv2.imread('path.tif', 1)