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@hzqtc
Last active December 16, 2015 10:28
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Compare two image mathematically using Perceptual Hash Algorithm. http://hzqtc.github.io/2013/04/image-duplication-detection.html
#!/usr/bin/python
import sys
from PIL import Image
def avhash(im):
if not isinstance(im, Image.Image):
im = Image.open(im)
im = im.resize((8, 8), Image.ANTIALIAS).convert('L')
avg = reduce(lambda x, y: x + y, im.getdata()) / 64.
return reduce(lambda x, (y, z): x | (z << y),
enumerate(map(lambda i: 0 if i < avg else 1, im.getdata())),
0)
def hamming(h1, h2):
h, d = 0, h1 ^ h2
while d:
h += 1
d &= d - 1
return h
if __name__ == '__main__':
if len(sys.argv) != 3:
print "Usage: %s img1 img2" % sys.argv[0]
else:
img1 = sys.argv[1]
img2 = sys.argv[2]
hash1 = avhash(img1)
hash2 = avhash(img2)
dist = hamming(hash1, hash2)
print "hash(%s) = %d\nhash(%s) = %d\nhamming distance = %d\nsimilarity = %d%%" % (img1, hash1, img2, hash2, dist, (64 - dist) * 100 / 64)
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