python - 如果大于某个阈值，则将灰度图像中的像素着色为红色

Question

计算出两个灰度图像(img1 和 img2)的像素差异后，我必须设置一个特定的阈值，即 diff 的平均值。现在，如果 img1 中的像素值 > 阈值，我必须将该像素着色为红色。如何将该像素设置为红色并将其他像素设置为灰度？我熟悉通过将大于阈值的像素值指定为 1 并将其他像素值指定为 0 来生成二进制掩码，但我想将该像素着色为红色。

img1 = cv2.imread(path,0)
img2 = cv2.imread(path,0)

diff = cv2.absdiff(img1, img2)
threshold=int(np.mean(diff))

Answer 1

你可以做这样的事情，从以下开始:

import cv2
img1 = cv2.imread('Bean.jpg',0)
img2 = cv2.imread('saltnpepperBean.jpg',0)

diff = cv2.absdiff(img1, img2)
threshold=int(np.mean(diff))

# Make colour version of input image so we can put red pixels in it
resultRGB = cv2.cvtColor(img1,cv2.COLOR_GRAY2BGR)

# Colorize all pixels above threshold with red 
resultRGB[diff>3*threshold] = 0,0,255

# Save to disk
cv2.imwrite('result.jpg',resultRGB)