Yomu

Pure Dart QR Code & Barcode Reader Library

Yomu is a zero-dependency pure Dart implementation of a QR code and barcode reader library. It works in any Dart environment including Flutter, Dart CLI applications, and server-side Dart.

✨ Why Yomu?

• 📦 Zero Dependencies: No external package dependencies. Keep your app's dependency graph clean.
• 🎯 Pure Dart: No C++/Native code. Works instantly on Web (Wasm/JS), Desktop, and Mobile without build issues.
• 🚀 High Performance: Full HD in ~4.4ms, 4K in ~9ms on M4 MacBook Air (AOT). Fast enough for real-time scanning.
• 🛡️ Robust & Tested: Comprehensive test coverage. Tested against hundreds of distorted, noisy, and unevenly lit images.

🚀 Quick Start

QR Code + All Barcodes

import 'package:yomu/yomu.dart';

void main() {
  // Create a YomuImage container
  final image = YomuImage.rgba(
    bytes: imageBytes,
    width: 300,
    height: 300,
  );

  // Decode QR codes and all barcode formats
  final result = Yomu.all.decode(image);
  print('Decoded: ${result.text}');
}

QR Code Only

// For QR code only scanning
final result = Yomu.qrOnly.decode(YomuImage.rgba(
  bytes: imageBytes,
  width: width,
  height: height,
));

📖 API Reference

Yomu Class

The main entry point class.

Constructor / Static	Description
Yomu.all	QR codes + all barcode formats
Yomu.qrOnly	QR codes only
Yomu.barcodeOnly	1D barcodes only
Yomu({enableQRCode, barcodeScanner})	Custom configuration

Method	Description
decode()	Decode the first QR code or barcode in an image
decodeAll()	Detect and decode all QR codes in an image

YomuImage Class

A platform-agnostic container for image data.

Factory	Description
YomuImage.rgba()	Create from RGBA bytes (4 bytes/pixel)
YomuImage.bgra()	Create from BGRA bytes (4 bytes/pixel)
YomuImage.grayscale()	Create from grayscale bytes (1 byte/pixel)
YomuImage.yuv420()	Create from Y-plane of YUV420 camera image

🔧 Support Status

Encoding Modes (QR)

Mode	Support
Numeric	✅
Alphanumeric	✅
Byte (Latin-1/UTF-8)	✅
Kanji	✅
ECI	❌ Not Supported

1D Barcode Support

Format	Support	Description
EAN-13	✅	International retail (includes JAN)
EAN-8	✅	Small products
UPC-A	✅	North American retail
Code 128	✅	Logistics, high-density
Code 39	✅	Industrial, alphanumeric
ITF	✅	Interleaved 2 of 5, logistics
Codabar	✅	Libraries, blood banks

🎯 Performance

Run the benchmark suite:

uv run scripts/benchmark_runner.py

Standard Images (≤1000px)

• Environment: M4 MacBook Air (2024), AOT Compiled

Mode	Avg Decode Time
AOT	~0.92ms
JIT	~1.30ms

Large Images (Fused Downsampling)

Images >1MP are automatically processed with a fused conversion step for optimal performance.

Resolution	Avg Decode Time
4K (3840×2160)	~9.0ms
Full HD (1920×1080)	~4.4ms

License

MIT License - see LICENSE for details.