Audio & Music Production (File Formats): open-source projects that exist because someone reverse engineered a closed product, sorted by GitHub stars.
Music notation and tab rendering library that imports Guitar Pro 3-8 files
Open-source tablature editor with Guitar Pro and Power Tab importers
Guitar tablature editor that imports Power Tab and Guitar Pro files
Reads, writes and manipulates Guitar Pro GP3/GP4/GP5 tablature files
Java library for parsing Pioneer rekordbox export databases and track analysis files
Reverse engineered parsers for Ableton Live and FL Studio project files
Parser and editor for FL Studio project (.flp) files
Rust library for parsing Pioneer rekordbox device exports
Guitar Pro tablature player written in Rust
Tools for editing and analyzing Ableton Live sets
Offline toolchain for Bitwig Studio's Nitro DSP format
Parser for Avid Pro Tools session files, used by Ardour for import
Tools for the MDX music format of the Sharp X68000
Documentation and parsers for Serato DJ Pro GEOB metadata tags
JavaScript parser for the Guitar Pro 5 file format
Audio player supporting many exotic multi-platform game and tracker music formats
Reverse engineered Traktor Pro .tsi controller mapping file format
Converts Guitar Pro 3-7 files to MIDI, simulating bends and effects
Rust library to parse and write Guitar Pro files
Converts Logic Pro .logicx projects to Ableton Live .als sets
Guitar Pro file parser
Editor for Akai MPC 1000/2500/500 program files and samples
Extracts Native Instruments Kontakt NKX monolith sample containers
Tools and reverse-engineering documentation for the Ensoniq Mirage sampler
Converts Finale .musx scores to MusicXML
Node.js library to manage Serato crates programmatically
FL Studio FLP file format parser and viewer
Reads Serato .crate files and returns columns and songs
File utility for Ensoniq EPS/ASR sampler disks and images
Converter that extracts and translates Finale .musx files to open formats
Reverse-engineering toolkit for Logic Pro .logicx project bundles
C library for parsing FL Studio .flp project files
Converts classic Mac OS 'snd ' resources and System 7 sound files to WAV
C++17 object model for the EnigmaXML data inside Finale .musx files
Python library for reading and writing Serato DJ crates
PlayStation Sound Format (PSF) player with unofficial patches
Python library for opening Band-in-a-Box song files
Builds, reads and exports Akai S1000/S2000/S3000 sampler CD images
Perl module to analyse Band-in-a-Box data files
Converts Cubase .cpr projects to REAPER .RPP via a reverse-engineered project format
Handler for MaxYMiser .MYS/.MYV chiptune files, documenting their reverse-engineered format