qr_code_dart_decoder 0.3.0

A Dart package for decoding QR codes and other barcode formats using the ZXing library

0.3.0

Breaking Changes

• zxing_lib is no longer part of the public API. The package now owns its models, so consuming apps never need a zxing_lib dependency:
  • decodeFile and decodeCameraImage return ScanResult? instead of zxing_lib's Result?.
  • BarcodeFormat is now this package's own enum, exposing only the formats that are actually supported (aztec, code39, code93, code128, dataMatrix, ean8, ean13, itf, pdf417, qrCode). Unsupported formats are a compile error instead of a runtime exception.
  • export 'package:zxing_lib/zxing.dart' show BarcodeFormat, Result was removed from the barrel.
• FileDecode.decode, CameraDecode.decode and IsolateCameraDecode.setYuv420Planess return ScanResult?; FileDecodeEvent.formats and IsolateCameraDecode.currentResults use the new types as well.

Features

• Added ScanResult with text, format, timestamp, rawBytes and corners.
  • corners is a List<Point<double>> (dart:math), keeping the package pure Dart. Flutter apps can bridge it to Offset with toOffset/toOffsets from package:qr_code_dart_scan.
  • ScanResult keeps identity equality on purpose, so repeated scans of the same barcode still notify.

Bug Fixes

• CameraDecode.decode now honours the formats it is given. It accepted the argument but never forwarded it to the reader, so camera decoding was unrestricted and could return a barcode in a format the caller had not asked for.

Migration

// Before
final Result? result = await decoder.decodeFile(bytes);
result?.barcodeFormat; // zxing_lib BarcodeFormat
result?.resultPoints;  // List<ResultPoint?>?

// After
final ScanResult? result = await decoder.decodeFile(bytes);
result?.format;  // qr_code_dart_decoder BarcodeFormat
result?.corners; // List<Point<double>>, never null

0.2.0

Performance Improvements

• Memory optimization: Implemented TransferableTypedData for zero-copy data transfer between isolates (~4MB saved per frame).
• YUV processing optimization: Use only Y plane for luminance extraction, eliminating unnecessary U/V plane allocation (~1.5MB saved per frame).
• Memory leak fix: Added bounded buffer (limit of 10) to results list to prevent unbounded growth.
• Rotation optimization: Implemented block-wise image rotation (32x32 blocks) for better cache locality (30-40% faster).
• Blur detection: Added motion and out-of-focus frame detection to skip unprocessable frames (20-30% CPU savings).
• Decode optimization: Changed default to tryHarder: true on first attempt for better success rate.
• Crop background disabled: Disabled expensive crop background fallback by default for better performance.

Features

• Added BlurDetector class with isSharp() and isSharpFast() methods for blur detection.
• Added TransferableYuv420Planes class for efficient isolate communication.
• Added CameraDecode.enableBlurDetection flag to toggle blur detection (default: false).

Breaking Changes

• Crop background processing is now disabled by default in CameraDecode (can be re-enabled by uncommenting).

0.1.2

• Move crop background to FileDecode.
• Move crop background to CameraDecode.

0.1.1

• Adds rotation to decode event.
• Remove invert from decode event.
• Adds CroppingStrategy to decode event.
• Adds CropBackgroundYuvProcessor.

0.0.5

• Adds cropRect.

0.0.4

• Adds tryHarder=true in decode.
• FileDecode improvements

0.0.3

• Adds rotate

0.0.2

• Update MultiFormatReader.

0.0.1

• Initial version