image-hash-native

A fast, native Node.js addon for calculating image hashes (Average Hash, Difference Hash, Perceptual Hash) and comparing them using Hamming distance.

Installation

``bash
npm install image-hash-native

or

pnpm add image-hash-native
`

Usage

This library operates on raw image buffers (RGB). You can use image processing libraries like sharp to convert images into the required format.

$3

`javascript
const { aHash, dHash, pHash, hamming } = require('image-hash-native');
const sharp = require('sharp');

(async () => {
// Read an image and convert to raw RGB buffer
const { data, info } = await sharp('image.jpg')
.raw()
.toBuffer({ resolveWithObject: true });

// Calculate hashes
const ah = aHash(data, info.width, info.height);
const dh = dHash(data, info.width, info.height);
const ph = pHash(data, info.width, info.height);

console.log(Average Hash: ${ah.toString(16)});
console.log(Difference Hash: ${dh.toString(16)});
console.log(Perceptual Hash: ${ph.toString(16)});

// Compare hashes
const distance = hamming(ah, ph);
console.log(Hamming Distance: ${distance});
})();
`

API

$3

Calculates the Average Hash.
- buffer: Buffer - Raw image data (RGB).
- width: number - Image width.
- height: number - Image height.
- Returns: bigint - The 64-bit hash.

$3

Calculates the Difference Hash.
- buffer: Buffer - Raw image data (RGB).
- width: number - Image width.
- height: number - Image height.
- Returns: bigint - The 64-bit hash.

$3

Calculates the Perceptual Hash.
- buffer: Buffer - Raw image data (RGB).
- width: number - Image width.
- height: number - Image height.
- Returns: bigint - The 64-bit hash.

$3

Calculates the Hamming distance between two hashes.
- hash1: bigint
- hash2: bigint
- Returns: number` - The number of differing bits (0-64).