PsCore

PsCore contains the pure Dart binary primitives shared by Focale's Photoshop format packages. It prevents AbrKit, AcvKit, AslKit, CshKit, PatKit and PsdKit from maintaining subtly different implementations of the same codecs.

The package currently provides:

• bounds-checked big-endian binary readers and writers;
• a complete Photoshop Action Descriptor model, reader, and writer;
• every standard descriptor OSType and object-reference form;
• bounded descriptor depth and value counts for untrusted input;
• PackBits row encoding and decoding;
• a shared Photoshop pattern-record model, bounded decoder, and encoder;
• raw and PackBits pattern planes at 1, 8, 16, and 32 bits;
• profile-independent RGBA previews for standard Photoshop color modes;
• tone curves, vector paths, and preset hierarchies;
• layer-style colors, gradients, contours, effects, and blending options, with typed views over existing descriptors and builders for new ones;
• format, write, and warning base types that every format package extends, so one on PsFormatException clause catches errors from any of them.

Platform support

The package is pure Dart and runs on native platforms, WebAssembly, and JavaScript.

comp Action Descriptor values retain every signed 64-bit integer on all three targets. Read PsLargeIntegerValue.exactValue as a BigInt, or construct one with PsLargeIntegerValue.fromBigInt(value: value). The existing const integer constructor remains available. intValue is nullable when the target cannot represent a value exactly; the compatibility value getter throws StateError in that case instead of rounding it. Integer descriptor projections also return null for an unrepresentable value.

PsBinaryReader.readBigInt64 and PsBinaryWriter.writeBigInt64 provide the same exact signed range for other binary structures. Ordinary readInt64/writeInt64 and 64-bit length fields continue to use int; JavaScript rejects values beyond psMaxExactInteger for those APIs. Native and WebAssembly integer APIs retain the platform's signed 64-bit range.

Usage

import 'dart:typed_data';

import 'package:pscore/pscore.dart';

final PsBinaryReader reader = PsBinaryReader(bytes: bytes);
final int version = reader.readUint16();

final PsDescriptor descriptor = PsDescriptorCodec.decode(descriptorBytes);
final PsDescriptorValue? name = descriptor.value('Nm  ');

final Uint8List encoded = PsDescriptorCodec.encode(descriptor);

Container packages can reuse the pattern-record decoder while controlling source preservation and decoded-memory limits:

final PsPatternDecodeResult decoded = PsPatternRecordDecoder.decode(
  reader: reader,
  kind: PsPatternRecordKind.standalone,
  options: const PsPatternDecodeOptions(
    preserveChannelData: false,
    preserveRecordData: false,
  ),
);
final PsPatternImage preview = decoded.pattern.renderRgba8();
final Uint8List patternBytes = PsPatternRecordEncoder.encode(
  pattern: decoded.pattern,
  kind: PsPatternRecordKind.standalone,
);

Built for Focale, an advanced local image editor. Discover what these packages make possible in a real creative workflow.