Phashion is a Ruby wrapper around the pHash library, "perceptual hash", which detects duplicate and near duplicate multimedia files (images, audio, video). The wrapper currently only supports images.
[See an overview of Phashion on Mike's blog] (http://www.mikeperham.com/2010/05/21/detecting-duplicate-images-with-phashion/).
You install it just like any other Ruby gem:
gem install phashion
Phashion is somewhat involved to install as it has a few dependencies. Phashion
wrapps these dependencies into a custom tarball that is built locally just
for this gem so you don't have to do anything special. Look in the
ext/phashion_ext folder for more details.
Because of this complexity, it is possible the gem install will fail on your platform. Phashion has been tested on:
- Mac OSX 10.6
- Mac OSX 10.9
- Ubuntu 8.04
- Ubuntu 12.04
Please open a GitHub issue if you have installation problems.
If you have an error upon install, like:
ld: library not found for -ljpeg
you need to install libjpeg. If you're on a Mac, you can use
homebrew brew install libjpeg or
ports port install jpeg .
require 'phashion'
img1 = Phashion::Image.new(filename1)
img2 = Phashion::Image.new(filename2)
img1.duplicate?(img2)
--> true
In order to detech duplicate alpha PNGs, the gem uses a custom version of pHash 0.9.6. The customization is limited to only these changes, [westonplatter/phash@ff255d2] (https://github.com/westonplatter/phash/commit/ff255d2d3f93c841b98923ecbde997027f21ae36). The gem will be moving back to the pHash master branch once it supports detection of alpha PNG file types. Testing
To run the test suite:
bundle
rake compile
rake
Mike Perham, http://mikeperham.com, http://twitter.com/mperham, mperham AT gmail.com
Copyright (c) 2010-2014 Mike Perham. See LICENSE for details.