cvtcolor rgb to gray code example

Example 1: convert image to grayscale opencv

img_gray_mode = cv2.imread(path, cv2.IMREAD_GRAYSCALE)

Example 2: cvtcolor rgb to gray

cv::Mat img
cv::cvtColor(img, img, CV_BGR2GRAY);

Example 3: cv2.cvtcolor grayscale

gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)