yomu 1.1.0

Pure Dart QR code and barcode reader library with zero dependencies.

CHANGELOG

1.1.0

Features

• Try-Harder Mode (default on): Yomu.decode now runs escalating retry strategies when the fast path fails, significantly improving the detection rate (fixture corpus: 84.3% -> 95.5%, 167/198 -> 189/198). Successful scans are unaffected; retries only run on images the fast path cannot decode.
  • Corner grid search: per-axis dimension candidates plus a grid search of the bottom-right corner rescue perspective-distorted codes.
  • Despeckle retry: a word-parallel 3x3 majority filter (BitMatrix.majority3x3) recovers codes under salt & pepper noise (validated up to 20% pixel noise).
  • Tolerant finder: clusters raw row-scan hits without the strict vertical cross-check, recovering slanted finder patterns under strong perspective.
  • Full-resolution retry: re-runs detection without downsampling when a downsampled pass fails, recovering small codes in high-resolution frames.
  • Retries are bounded by a deterministic work budget and grid-search deduplication, so undecodable inputs cannot make the failure path pathologically slow.
  • Set tryHarder: false for the previous fast-only behavior (latency-critical per-frame scanning).
• decodeAll retry passes: multi-code scanning applies the same strategy. Detected-but-undecodable codes get the corner-grid rescue, and a pass that finds nothing escalates to despeckle and a full-resolution pass (a noisy 3-code sheet and two 90px codes in a 4K frame go from 0 to fully decoded).
• Yomu.realtime preset: all formats with tryHarder disabled, tuned for per-frame camera scanning where a missed frame is cheaper than a slower failure path.
• With tryHarder enabled, a detected-but-undecodable QR code now falls through to barcode scanning instead of propagating a DecodeException.

Test fixtures

• Fixture ladders now bracket the current capability boundary on both sides, with boundary-pinning tests on each side (see the Supported Image Classes table in the README).
• New distortion axes derived from the modern imaging pipeline: low-light Gaussian noise, JPEG quantization artifacts, specular glare, screen moire, and a composite casual-scan recipe (mild perspective + lighting gradient + blur) that demonstrates composition lowering the single-axis boundary.
• The legacy perspective_{x,y} fixtures above 0.2 cropped the finder patterns out of the canvas (invalid test images); they are replaced by a padded transform that keeps the code fully visible.
• fixtures/unsupported_images now contains only images beyond the capability boundary; everything rescued by the retry strategies moved to fixtures/distorted_images.

1.0.0

Initial stable release.

Features

• Pure Dart Implementation: A zero-dependency QR code and barcode reader library. No native code required, making it highly portable across Flutter, Web, and Server-side Dart.
• QR Code Support:
  • Full support for QR Code versions 1 to 40.
  • Supports all error correction levels (L, M, Q, H).
  • Robust multi-QR detection and decoding in a single image.
  • High resilience against perspective distortion, rotation, and uneven lighting.
• 1D Barcode Support:
  • Retail: EAN-13 (including JAN), EAN-8, UPC-A.
  • Industrial: Code 128, Code 39, ITF (Interleaved 2 of 5), Codabar.
• High Performance:
  • Specifically optimized for AOT compilation and performance.
  • Efficiently handles high-resolution images (> 1MP) using internal fused downsampling and conversion.
  • Capable of real-time decoding on mobile and desktop platforms.
• Flexible Image API: Platform-agnostic YomuImage container supporting various pixel formats including RGBA, BGRA, Grayscale, and YUV420 (camera stream Y-plane).