This is my first use of midi in Processing. I do not use the MidiBus library for Processing. Instead, I try to use the standard midi package in Java. The SE8 standard Java package also contains the javadoc documentation.
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The Processing source code and sample midi files are in the Magicandlove GitHub repository. The midi example files are downloaded from the midiworld website.
The code basically needs a Synthesizer class to render midi instruments into audio and a Sequencer class to playback the midi sequence.
Synthesizer synth = MidiSystem.getSynthesizer();
Sequencer player = MidiSystem.getSequencer();
synth.open();
player.open();
All the midi music files are in the data folder of the Processing sketch. To playback each piece of midi music, we need to convert each into a Java File object and use the following code to playback it. The variable f is a File object instance containing the midi file in the data folder.
Sequence music = MidiSystem.getSequence(f);
player.setSequence(music);
player.start();