libOPNMIDI

libOPNMIDI is a free Software MIDI synthesizer library with OPN2 (YM2612) and OPNA (YM2608) emulation.

OPNMIDI Library: Copyright (c) 2017-2026 Vitaly Novichkov admin@wohlnet.ru

Library is based on core of the libADLMIDI, a MIDI playing library with OPL3 emulation.

• Semaphore-CI:
• AppVeyor CI:
• Travis CI:

Tested on platforms

• Linux GCC 4.8, 4.9, 5.4 / CLang
• Mac OS X CLang (Xcode 7.x)
• Windows MinGW 4.9.x, 5.2
• Android NDK 12b/13
• OpenBSD
• Haiku
• Emscripten

Key features

• OPN2 emulation
• Rudimentary OPNA emulation
• Customizable bank of FM patches (You have to use the bank editor to create own soundbank)
• Stereo sound
• Number of simulated OPN2/OPNA chips can be specified as 1-100 (maximum 600 channels!)
• Pan (binary panning, i.e. left/right side on/off)
• Pitch-bender with adjustable range
• Vibrato that responds to RPN/NRPN parameters
• Sustain (a.k.a. Pedal hold) and Sostenuto enable/disable
• MIDI and RMI file support
• Real-Time MIDI API support
• MIDI and RMI file support
• loopStart / loopEnd tag support (Final Fantasy VII)
• 111'th controller based loop start (RPG-Maker)
• Use automatic arpeggio with chords to relieve channel pressure
• Support for multiple concurrent MIDI synthesizers (per-track device/port select FF 09 message), can be used to overcome 16 channel limit
• Partial support for GS and XG standards (having more instruments than in one 128:128 GM set and ability to use multiple channels for percussion purposes, and support for some GS/XG exclusive controllers)
• CC74 "Brightness" affects a modulator scale (to simulate frequency cut-off on WT synths)
• Portamento support (CC5, CC37, and CC65)
• SysEx support that supports some generic, GS, and XG features
• Full-panning stereo option (works for emulators only)

How to build

To build libOPNMIDI you need to use CMake:

mkdir build
cd build
cmake -DCMAKE_BUILD_TYPE=Release ..
make
sudo make install

License

The library is licensed under in it's parts LGPL 2.1+, GPL v2+, GPL v3+, and MIT.

• Nuked OPN2 emulator is licensed under LGPL v2.1+.
• GENS 2.10 emulator is licensed under LGPL v2.1+.
• MAME YM2612 emulator is licensed under GPL v2+.
• Genesis Plus GX emulator is licensed under GPL v2+.
• Neko Project II Kai (fmgen, developed by "cisc" cisc@retropc.net) OPNA emulator is licensed under MIT-compatible license.
• PMDWin emulator OPNA emulator is licensed under BSD 2-Clause.
• MAME YM2608 emulator is licensed under GPL v2+.
• Chip interfaces are licensed under LGPL v2.1+.
• File Reader class and MIDI Sequencer is licensed under MIT.
• Other parts of library are licensed under GPLv3+.

Available CMake options

• CMAKE_INSTALL_PREFIX - destination folder where libOPNMIDI will be installed. On Linux it is /usr/local/ by default.

• CMAKE_BUILD_TYPE - Build types: Debug or Release. Also MinSizeRel or RelWithDebInfo.

• WITH_MIDIPLAY - (ON/OFF, default OFF) Build demo MIDI player (Requires SDL2 and also pthread on Windows with MinGW)

• WITH_VLC_PLUGIN - (ON/OFF, default OFF) Compile VLC plugin. For now, works on Linux and VLC. Support for other platforms comming soon!

• WITH_WINMMDRV - (ON/OFF, default OFF) (Windows platform only) Compile the WinMM MIDI driver to use libOPNMIDI as a system MIDI device.

  • WITH_WINMMDRV_PTHREADS - (ON/OFF, default ON) Link libwinpthreads statically (when using pthread-based builds).
  • WITH_WINMMDRV_MINGWEX - (ON/OFF, default OFF) Link libmingwex statically (when using vanilla MinGW builds). Useful for targetting to pre-XP Windows versions.

• WITH_MIDI2VGM - (ON/OFF, default OFF) Build MIDI to VGM converter tool.

• WITH_DAC_UTIL - (ON/OFF, default OFF) Build YM2612 CH6 DAC testing utility.

• WITH_MIDI_SEQUENCER - (ON/OFF, default ON) Enable built-in MIDI sequencer to play loaded MIDI files. When you will disable MIDI sequencer, Real-Time functions only will work. Use this option when you are making MIDI plugin or real-time MIDI driver.

• USE_MAME_EMULATOR - (ON/OFF, default ON) Enable support for MAME YM2612 emulator. Well-accurate and fast on slow devices.

• USE_NUKED_EMULATOR - (ON/OFF, default ON) Enable support for Nuked OPN2 emulator. Very accurate, however, requires a very powerful CPU. Is not recommended for mobile devices!.

• USE_GENS_EMULATOR - (ON/OFF, default ON) Enable support for GENS 2.10 emulator. Very outdated and inaccurate, but fastest.

• USE_GX_EMULATOR - (ON/OFF, default OFF) Enable support for Genesis Plus GX emulator. (experimental!)

• USE_NP2_EMULATOR - (ON/OFF, default ON) Enable support for Neko Project 2 YM2608 emulator. Semi-accurate, but fast on slow devices.

• USE_MAME_2608_EMULATOR - (ON/OFF, default ON) Enable support for MAME YM2608 emulator. Well-accurate and fast on slow devices.

• WITH_HQ_RESAMPLER - (ON/OFF, default OFF) Build with support for high quality resampling (requires zita-resampler to be installed.

• WITH_MUS_SUPPORT - (ON/OFF, default ON) Enable support for DMX MUS format in built-in MIDI sequencer.

• WITH_XMI_SUPPORT - (ON/OFF, default ON) Enable support for AIL XMI format in built-in MIDI sequencer.

• WITH_UNIT_TESTS - (ON/OFF, default OFF) Also compile unit-tests of internal features.

• libOPNMIDI_STATIC - (ON/OFF, default ON) Build static library

• libOPNMIDI_SHARED - (ON/OFF, default OFF) Build shared library

You also can build library manually:

You need to make in the any IDE a library project and put into it next files (or include those files into subfolder of your exist project instead if you want to use it statically):

Useful macros

• BWMIDI_DISABLE_XMI_SUPPORT - Disables XMI to MIDI converter
• BWMIDI_DISABLE_MUS_SUPPORT - Disables MUS to MIDI converter
• OPNMIDI_DISABLE_MIDI_SEQUENCER - Completely disables built-in MIDI sequencer.
• OPNMIDI_USE_LEGACY_EMULATOR - Enables Gens 2.10 YM2612 emulator to be used. Nuked OPN2 is used by default if macro is not defined.

Public header (include)

• opnmidi.h - Library API, use it to control library

Internal code (src)

• opnbank.h - bank structures definition

• opnmidi_private.hpp - header of internal private APIs

• opnmidi.cpp - code of library

• opnmidi_load.cpp - Source of file loading and parsing processing

• opnmidi_midiplay.cpp - MIDI event sequencer

• opnmidi_opn2.cpp - OPN2 chips manager

• opnmidi_private.cpp - some internal functions sources

• opnmidi_bankmap.h - MIDI bank hash table

• opnmidi_bankmap.tcc - MIDI bank hash table (Implementation)

• opnmidi_cvt.hpp - Instrument conversion template

• opnmidi_ptr.hpp - Custom implementations of smart pointers for C++98

• file_reader.hpp - Generic file and memory reader

• chips/opn_chip_base.h - Header of base class over all emulation cores

• chips/opn_chip_base.tcc - Code of base class over all emulation cores

• chips/gens_opn2.h - Header of emulator frontent over Gens 2.10 emulator

• chips/gens_opn2.cpp - Code of emulator frontent over Gens 2.10 emulator

• chips/gens/Ym2612_ChipEmu.h - Gens 2.10 OPN2 Emulation header

• chips/gens/Ym2612_ChipEmu.cpp - Code of Gens 2.10 OPN2 emulator by Stéphane Dallongeville, improved by Shay Green

• chips/mame_opn2.h - Header of emulator frontent over MAME YM2612 emulator

• chips/mame_opn2.cpp - Code of emulator frontent over MAME YM2612 emulator

• chips/mame/mame_ym2612fm.h - MAME YM2612 Emulation header

• chips/mame/mame_ym2612fm.cpp - Code of MAME YM2612 emulator by Jarek Burczyński and Tatsuyuki Satoh, improved by Eke-Eke

• chips/nuked_opn2.h - Header of emulator frontent over Nuked OPN2 emulator

• chips/nuked_opn2.cpp - Code of emulator frontent over Nuked OPN2 emulator

• chips/nuked/ym3438.h - Nuked OPN2 Emulation header

• chips/nuked/ym3438.cpp - Code of Nuked OPN2 emulator by Alexey Khokholov

• chips/np2/* - Code of Neko Project 2 YM2608 emulator by cisc.

• chips/mamefm/* - Code of MAME YM2608 emulator by Jarek Burczynski and Tatsuyuki Satoh.

• wopn/* - WOPN bank format library

MIDI Sequencer

To remove MIDI Sequencer, define OPNMIDI_DISABLE_MIDI_SEQUENCER macro and remove all those files

• adlmidi_sequencer.cpp - MIDI Sequencer related source
• cvt_mus2mid.hpp - MUS2MID converter source (define BWMIDI_DISABLE_MUS_SUPPORT macro to remove MUS support)
• cvt_xmi2mid.hpp - XMI2MID converter source (define BWMIDI_DISABLE_XMI_SUPPORT macro to remove XMI support)
• fraction.hpp - Fraction number handling (Used by Sequencer only)
• midi_sequencer.h - MIDI Sequencer C bindings
• midi_sequencer.hpp - MIDI Sequencer C++ declaration
• midi_sequencer_impl.hpp - MIDI Sequencer C++ implementation (must be once included into one of CPP together with interfaces initializations)

Important: Please use GENS emulator only on mobile or any non-power devices because it requires very small CPU power. Nuked OPN2 emulator is very accurate (compared to real OPN2 chip), however, it requires a VERY POWERFUL device even for a single chip emulation and is a high probability that your device will lag and playback will be dirty and choppy. Use of MAME OPN2 is recommended in such cases.

Working demos

• Moondust MusPlay for Win32 and Win64 (also available for other platforms as part of Moondust Project) - a litt