Image Hashing with Python
dhash
http://www.hackerfactor.com/blog/index.php?/archives/529-Kind-of-Like-That.html http://blog.iconfinder.com/detecting-duplicate-images-using-python/
ahash
http://www.hackerfactor.com/blog/index.php?/archives/432-Looks-Like-It.html
phash
https://zh.wikipedia.org/wiki/%E7%A6%BB%E6%95%A3%E4%BD%99%E5%BC%A6%E5%8F%98%E6%8D%A2
Python Implementaion(too redundant)
https://github.com/JohannesBuchner/imagehash