image_hashing

NOTE: UNDER DEVELOPMENT!

A Dart library for generating perceptual hashes (AHash, PHash, DHash, WHash) from images, providing efficient single-image hash computation and comparison with pure Dart implementation.

Compatibility: Dart ^3.6.0

🚀 Getting Started

Installation

Method 1 (Recommended) With Dart:

dart pub add image_hashing

With Flutter:

flutter pub add image_hashing

Method 2 Add to pubspec.yaml:

dependencies:
  image_hashing: ^0.1.1

Then run:

dart pub get

Basic Usage

import 'package:image_hashing/image_hashing.dart';

void main() {
  final hasher = AHash(); // or other hasher types
  final hashRes = hasher.encodeImage("YourImageFile");
}

Currently only AHash is supported, to validate the whole process.

encodeImage will return you a String of hash value.

For AHash and PHash, it will be 64 bits (After hashing, you will obtain an $(8 \times 8)$ image).

For DHash, it will be 128 bits (Here, I decide to use both row difference and column difference to increase the countability, so you will obtain 2 $(8 \times 8)$ images).

WHash is still under-planning.

📦 Features

Core Feature 1: Different Hashing Methods

final ahasher = AHash();
final phasher = PHash();
final dhasher = DHash();
final whasher = WHash(); // Wavelet Transform Hashing dependency is under development

To encode an image:

final ahasher = AHash(useCV: false); // OpenCV compatibility is under development
final ahash = ahasher.encodeImage("YourImageFile");

Core Feature 2: Hamming Distances of Image Hashing After hashing, you can use the following function to calculate the Hamming Distances
```
final distance = hammingDistance(a, b, size: 64)
```
where a and b are the hash strings. size is 64 for AHash and PHash, 128 for DHash.

Result will in an int value.

🧪 Testing

Unit tests are under development. Currently only unit tests for hamming distance

dart test

🤝 Contributing

Workflow

Fork repository
Create feature branch:
```
git checkout -b feat/your-feature
```

Follow Conventional Commits:

git commit -m "feat: add new validation method"

Code Style

Follow the Effective Dart and analysis_options.yaml

📚 Documentation

📜 License

Full text at LICENSE

🚧 Maintenance Status

Basic functionalities are under development.

Please report issues via GitHub Issues