ImageHash

I wanna get the image hash based on pixels value. I reached this article: https://fullstackml.com/wavelet-image-hash-in-python-3504fdd282b5

Then I give a try:

1. Directly translate the code from python to C#. Failed because pywt.wavedec2 is too complicated and the search result are all about Matlab -_-

see csharp/Vision/Tools/ImageHelper.cs

2. Use IronPython. Failed because PIL library has many .pyd files (_imaging) which are not supported by IronPython.

see csharp/Vision/Runtime/Python.cs

3. Use Process and commandline, redirect the output. Worked.

see csharp/Vision/Runtime/PythonCommand.cs

4. If considering deployment, ImageHash can be a service with python backend. The simplest way. e.g. The media node has a copy: [Get hash of an image](http://nodes.chuci.info/media.html)

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Following is the original Readme

A image hashing library written in Python. ImageHash supports:

• average hashing (aHash)
• perception hashing (pHash)
• difference hashing (dHash)
• wavelet hashing (wHash)

Requirements

Based on PIL/Pillow Image, numpy and scipy.fftpack (for pHash) Easy installation through pypi.

Basic usage

>>> from PIL import Image
>>> import imagehash
>>> hash = imagehash.average_hash(Image.open('test.png'))
>>> print(hash)
d879f8f89b1bbf
>>> otherhash = imagehash.average_hash(Image.open('other.bmp'))
>>> print(otherhash)
ffff3720200ffff
>>> print(hash == otherhash)
False
>>> print(hash - otherhash)
36

The demo script find_similar_images illustrates how to find similar images in a directory.

Source hosted at github: https://github.com/JohannesBuchner/imagehash

Changelog

• 3.0: dhash had a bug: It computed pixel differences vertically, not horizontally.

  I modified it to follow dHash. The old function is available as dhash_vertical.

• 2.0: added whash
• 1.0: initial ahash, dhash, phash implementations.