接收错误：AttributeError：尝试调用openCV方法时，模块'cv2.cv2'没有属性'CompareHist'

Question

I'm trying to find the distance between two vectors using openCV's compareHist() method. I'm using opencv-contrib-python 3.4.2.17. If I try to use the compareHist() method as described in the documentation here https://docs.opencv.org/3.4.2/d6/dc7/group__imgproc__hist.html#gaf4190090efa5c47cb367cf97a9a519bd I get an error "AttributeError: module 'cv2.cv2' has no attribute 'CompareHist'"

Am I calling the method incorrectly, or am I using the documentation incorrectly?

My snippet of testing code is below for reference. Thanks.

import numpy as np
import cv2 as cv

img = cv.imread('../data/im3.jpg')
img2 = cv.imread('../data/im4.jpg')
gray = cv.cvtColor(img, cv.COLOR_BGR2GRAY)
gray2 = cv.cvtColor(img2, cv.COLOR_BGR2GRAY)

sift = cv.xfeatures2d.SIFT_create()
kp, des1 = sift.detectAndCompute(gray,None)
kp2, des2 = sift.detectAndCompute(gray2,None)


print(cv.CompareHist(des1[0], des2[0], CV_COMP_CORREL))

Answer 1

Try using cv.HISTCMP_CORREL instead of CV_COMP_CORREL in the CompareHist method like cv.CompareHist(des1[0], des2[0], CV_HISTCMP_CORREL) . It was renamed in the newer versions.

Refer to this post for more information.