c2pa_formats

Asset-container detection, C2PA manifest extraction and mutation, remote reference metadata, and hard-binding byte layouts for the Dart C2PA SDK.

Platforms

The package supports Dart VM, Flutter, and web through c2pa_io. It operates on random-access byte sources and sinks rather than filesystem APIs.

import 'package:c2pa_formats/c2pa_formats.dart';
import 'package:c2pa_io/c2pa_io.dart';

final result = await AssetHandlerRegistry().detect(
  MemoryByteSource(const []),
  fileExtension: 'jpg',
);
print(result.format);

See example/c2pa_formats.dart.

Security and defaults

Parsing and mutation are bounded by source sizes and checked ranges. ZIP paths and collection layouts are validated against traversal. This package does not perform network access; remote references are metadata only. Preserve the original asset when adopting a mutation workflow and validate the result.

Package relationships

c2pa_formats depends on c2pa_io and c2pa_codec. The high-level c2pa reader and builder select these handlers automatically.

Compatibility and limitations

The compatibility target is c2pa-rs c2pa-v0.90.22. Standalone C2PA support is complete for the tracked baseline. JPEG, PNG, TIFF/DNG, GIF, RIFF, MP3, FLAC, SVG, ISO BMFF, JPEG XL, and ZIP-family read/write paths are useful but full baseline parity is not claimed. PDF reading is tracked as complete; PDF mutation remains partial. Brotli compression is handled above this layer and generation is not available.

Licensed under the MIT License (LICENSE). As an alternative, you may instead use this package under the Apache License, Version 2.0 (LICENSE-APACHE), so the package is offered as MIT OR Apache-2.0, at your option. Copyright is held by contributors to c2pa_dart.