Midi Driver

Android midi driver using Sonivox EAS library. The library is available in Releases.

Licensed under Apache license.

Includes Sonivox EAS library rebuilt without spurious references to libutils and libcutils. The ARM versions have been build with the assembler source files.

Load DLS soundfont files

I have attempted to add code to load DLS soundfont files, which I have not been able to get working. The code is in the DLS branch and the relevent issue is Costum soundfont is possible?.

If anyone would like to take this up and attempt to get it working that would be much appreciated. I know Google know how it works because they have fixed a bug in it...

    Author: Eric Laurent <elaurent@google.com>
    Date:   Thu May 14 09:10:40 2015 -0700

    DLS parser: fix wave pool size check.

    Bug: 21132860.

Bugs

Google has fixed the 64 bit reverb bug: #15 - Fix math functions for 64-bit. The driver should now work correctly on all 64 bit devices.

The Sonivox library is now built as a static library and linked with the midi library. This should resolve problems with various android versions.

Use

Add the driver to your build.gradle with

allprojects {
    repositories {
        maven { url "https://jitpack.io" }
    }
}

and:

dependencies {
    implementation 'com.github.billthefarmer:mididriver:v1.24'
}

Constructor

The constructor has been made private and getInstance() methods added so it is not possible to have more than one instance in an app. See the demo app for an example.

Methods

    static MidiDriver getInstance() // Get instance of driver

    static MidiDriver getInstance(OnMidiStartListener l)

    void start() // Start the driver. Call from onResume().

    void stop()  // Stop the driver. Call from onPause();

    void addOnMidiStartListener(OnMidiStartListener l)

    void queueEvent(byte[]) // Send a midi message. This method now just
                            // calls write()

Listener

    void onMidiStart() // This is called when the driver has started so
                       // that program change messages, etc, may be sent.
                       // This is now somewhat redundant but has been left in.

Native Methods

    boolean init()  // Return true on success, or false on failure.
	
    int[] config()  // Return a four element array of ints with part of
                    // the EAS config:

        config[0] = pLibConfig->maxVoices;
        config[1] = pLibConfig->numChannels;
        config[2] = pLibConfig->sampleRate;
        config[3] = pLibConfig->mixBufferSize;

    boolean write(byte buffer[]) // Writes midi data to the Sonivox
                                 // synthesizer. The length of the array
                                 // should be the exact length of the
                                 // message or messages. Returns true
                                 // on success, false on
                                 // failure.

    boolean setVolume(int volume) // Set master volume for EAS
                                  // synthesizer (between 0 and 100).
                                  // Returns true on success, false on
                                  // failure.
    boolean setReverb(int preset) // Set Reverb effect preset for EAS
                                  // synthesizer (value from
                                  // ReverbConstants). Returns true
                                  // on success, false on failure.

    boolean shutdown() // Shut down the synthesizer. Returns true on
                       // success, false on failure.

C/C++ Native Functions

#include "midi.h"

    jboolean midi_init()  // Return true on success, or false on failure.
    jboolean midi_write(EAS_U8 *bytes, jint length)
                                 // Writes midi data to the Sonivox
                                 // synthesizer. The length of the array
                                 // should be the exact length of the
                                 // message or messages. Returns true
                                 // on success, false on
                                 // failure.
    jboolean midi_setVolume(jint volume)
                                  // Set master volume for EAS
                                  // synthesizer (between 0 and 100).
                                  // Returns true on success, false on
                                  // failure.
    jboolean midi_setReverb(jint preset)
                                  // Set Reverb effect preset for EAS
                                  // synthesizer. Preset could be:
                                  //   -1: turn reverb off
                                  //    0: large hall
                                  //    1: hall
                                  //    2: chamber
                                  //    3: room.
                                  // Returns true on success, false on
                                  // failure.
    jboolean midi_shutdown() // Shut down the synthesizer. Returns true on
                             // success, false on failure.

Native library locations

The location of the native libmidi.so libraries for building native code may be found by doing a search in the app build folder. This location may change with different versions of the android build tools.

$ find ./build -name libmidi.so
./build/intermediates/merged_native_libs/debug/out/lib/arm64-v8a/libmidi.so
./build/intermediates/merged_native_libs/debug/out/lib/armeabi-v7a/libmidi.so
./build/intermediates/merged_native_libs/debug/out/lib/x86/libmidi.so
./build/intermediates/merged_native_libs/debug/out/lib/x86_64/libmidi.so
./build/intermediates/merged_native_libs/release/out/lib/arm64-v8a/libmidi.so
./build/intermediates/merged_native_libs/release/out/lib/armeabi-v7a/libmidi.so
./build/intermediates/merged_native_libs/release/out/lib/x86/libmidi.so
./build/intermediates/merged_native_libs/release/out/lib/x86_64/libmidi.so
./build/intermediates/stripped_native_libs/debug/out/lib/arm64-v8a/libmidi.so
./build/intermediates/stripped_native_libs/debug/out/lib/armeabi-v7a/libmidi.so
./build/intermediates/stripped_native_libs/debug/out/lib/x86/libmidi.so
./build/intermediates/stripped_native_libs/debug/out/lib/x86_64/libmidi.so
./build/intermediates/stripped_native_libs/release/out/lib/arm64-v8a/libmidi.so
./build/intermediates/stripped_native_libs/release/out/lib/armeabi-v7a/libmidi.so
./build/intermediates/stripped_native_libs/release/out/lib/x86/libmidi.so
./build/intermediates/stripped_native_libs/release/out/lib/x86_64/libmidi.so