dart_gp_tab_reader

A pure-Dart, read-only reader for Guitar Pro tablature files — GP3, GP4, GP5, GP6 (.gpx) and GP7/GP8 (.gp).

The GP3–5 binary readers are a Dart port of PyGuitarPro by Sviatoslav Abakumov, which is itself a port of AlphaTab / TuxGuitar; the binary format parsing logic mirrors PyGuitarPro closely. GP6–8 files carry a GPIF (score.gpif) XML score inside a container — a zip archive for .gp, the proprietary BCFS/BCFZ filesystem for .gpx (decoder ported from alphaTab) — and are parsed into the same model tree, so callers don't need to care which format a file came in: parseGp detects it from the bytes.

Usage

import 'dart:io';
import 'package:dart_gp_tab_reader/dart_gp_tab_reader.dart';

void main() {
  final bytes = File('song.gp5').readAsBytesSync();
  final Song song = parseGp(bytes);

  print('${song.title} — ${song.artist} @ ${song.tempo} bpm');
  for (final track in song.tracks) {
    print('Track: ${track.name} (${track.strings.length} strings)');
  }
}

See example/example.dart for a runnable version.

The returned Song is a tree of Track → Measure → Voice → Beat → Note. Durations are expressed in ticks (Duration.quarterTime == 960 per quarter note); convert to seconds against Song.tempo if you need wall-clock timing.

License

Because this is a derivative of PyGuitarPro, it is distributed under the GNU LGPL-3.0 (see LICENSE). It is intentionally kept as a separate package: an application may depend on it (e.g. via a normal pub dependency) without the LGPL extending to the application's own proprietary code, as long as this package's source remains available and replaceable.

Original work © Sviatoslav Abakumov and the PyGuitarPro contributors.

Trademark notice

"Guitar Pro" is a registered trademark of Arobas Music. This project is an independent, unofficial reader for the Guitar Pro file format and is not affiliated with, endorsed by, or sponsored by Arobas Music. The name is used only descriptively to identify the supported file format.