Image difference

image-diff

#!/usr/bin/env python

import cv2
import math
import numpy
from   argparse import ArgumentParser

def main():
    ap = ArgumentParser('image difference tool')
    ap.add_argument('--img1', required = True)
    ap.add_argument('--img2', required = True)
    ap.add_argument('--out' , required = True)
    args = ap.parse_args()

    try:
        image_1 = cv2.imread(args.img1)
    except Exception:
        print('Failed to open img1')
        return 1

    try:
        image_2 = cv2.imread(args.img2)
    except Exception:
        print('Failed to open img2')
        return 1

    try:
        diff_img = image_2 - image_1
    except Exception:
        print('Failed to diff images')
        return 1

    # split channels
    r_chan, g_chan, b_chan = cv2.split(diff_img)

    cv2.imwrite(args.out, diff_img)
    cv2.imwrite('r.%s' % args.out, r_chan)
    cv2.imwrite('g.%s' % args.out, g_chan)
    cv2.imwrite('b.%s' % args.out, b_chan)

    print('''
Max Difference:
r -> {max_r}
g -> {max_g}
b -> {max_b}
    '''.format(max_r = numpy.max(numpy.fabs(r_chan))
             , max_g = numpy.max(numpy.fabs(g_chan))
             , max_b = numpy.max(numpy.fabs(b_chan))))


    return 0

if __name__ == '__main__':
    from sys import exit
    exit(main())