kodus/image-hash

kodus/image-hash

This library implements the aHash, dHash and pHash image-hashing algorithms as described in this article., _(*1)

It's based on this implementation but with a loader-abstraction for GD and Imagick support, added tests, and a benchmark., _(*2)

Usage

To compare two images:, _(*3)

use Kodus\ImageHash\ImageHasher;

$hasher = new ImageHasher();

$a_hash = $hasher->pHash("path/to/image-a.jpg");
$b_hash = $hasher->pHash("path/to/image-b.jpg");

if ($hasher->getDistance($a_hash, $b_hash) <= 2) {
    echo "same!";
} else {
    echo "different.";
}

Substitute calls to pHash() for aHash() or dHash() to use another algorithm, but note that getDistance() only makes sense for two hashes computed using the same algorithm., _(*4)

Hashes are returned as a binary-mask string - use base_convert if you need a decimal or hex value., _(*5)

Hacking

To run the tests:, _(*6)

php test/test.php

To run the benchmark:, _(*7)

php test/benchmark.php

If you hack on this library, be sure to run the benchmark before/after making changes., _(*8)