compare images with opencv

diff.py

import cv2
import numpy as np
from skimage.measure import compare_ssim as ssim

def mse(imageA, imageB):
    # the 'Mean Squared Error' between the two images is the
    # sum of the squared difference between the two images;
    # NOTE: the two images must have the same dimension
    err = np.sum((imageA.astype("float") - imageB.astype("float")) ** 2)
    err /= float(imageA.shape[0] * imageA.shape[1])

    # return the MSE, the lower the error, the more "similar"
    # the two images are

def diff_remove_bg(img0, img, img1):
    d1 = diff(img0, img)
    d2 = diff(img, img1)
    return cv2.bitwise_and(d1, d2)

x1 = cv2.imread("images/xx1.jpg")
x2 = cv2.imread("images/xx12.jpg")

x1 = cv2.cvtColor(x1, cv2.COLOR_BGR2GRAY)
x2 = cv2.cvtColor(x2, cv2.COLOR_BGR2GRAY)

absdiff = cv2.absdiff(x1, x2)
cv2.imwrite("images/absdiff.png", absdiff)

diff = cv2.subtract(x1, x2)
result = not np.any(diff)

m = mse(x1, x2)
s = ssim(x1, x2)

print "mse: %s, ssim: %s" % (m, s)

if result:
    print "The images are the same"
else:
    cv2.imwrite("images/diff.png", diff)
    print "The images are different"

can I change the imread files as .png and print the output

When I try to change imread files as .png .
I got error like this. can you please help me
absdiff = cv2.absdiff(x1, x2)

error: OpenCV(4.2.0) C:\projects\opencv-python\opencv\modules\core\src\arithm.cpp:669: error: (-209:Sizes of input arguments do not match) The operation is neither 'array op array' (where arrays have the same size and the same number of channels), nor 'array op scalar', nor 'scalar op array' in function 'cv::arithm_op'

Could you pls. modify the above code for comparing images from two different folders. Code will compare first image from first folder and second image from second folder and then keep comparing all images one by one and share the result in a third folder. I am new to python and Open CV and tried but didn't work. Could you help here...

Hi Arvinder,

Please add your two input folders path here:
x1 = cv2.imread("images/xx1.jpg")
x2 = cv2.imread("images/xx12.jpg")

Also, add your output folder path here:
cv2.imwrite("images/absdiff.png", absdiff)
cv2.imwrite("images/diff.png", diff)