如何从图像中提取指定坐标的像素

Question

I am extracting some pixels from an image using the following:

import cv2
import numpy as np
img = cv2.imread('random.png')
targets = np.array([[111, 111], [222, 222], [333, 333]], dtype=np.uint8)
targeted = []
for x, y in targets:
    targeted.append(img[x, y])

Is there a more pythonic or vectorized method to do it in one line instead of this for loop?

Answer 1

Perhaps this is what you are looking for (in the place of the for loop):

targeted = img[tuple(targets.T)].tolist()

If you don't want to convert into a list:

targeted = img[tuple(targets.T)]

Answer 2

I got the output after renaming r to targets. It could be because your image object is None. Can you check:

1. Whether path/image filename is correct
2. Whether the image has a size of more than 111 (which is the minimum location)(