midi_pygame.py

import threading

import pygame.midi as midi


known_devices = [
    'Launchkey Mini MIDI 1',
    'Launchkey Mini LK Mini MIDI',
]

class MidiPygame:
    events = {
        8: 'noteoff',
        9: 'noteon',
        11: 'controller',
        12: 'pgmchange',
    }

    def __init__(self, debug=False):
        print('Using Pygame MIDI interface')
        self.debug = debug

        midi.init()

        self.midi_input = None
        for device_id in range(midi.get_count()):
            interf, name, is_input, is_output, opened = midi.get_device_info(device_id)
            interf = interf.decode('utf-8')
            name = name.decode('utf-8')
            imode = 'input' if is_input else 'output' if is_output else 'none'
            iopen = '(open)' if opened else ''

            if self.debug:
                print(f'{interf} / {name} ({imode}) {iopen}')

            if name in known_devices and is_input:
                self.midi_input = midi.Input(device_id)
                self.midi_input.name = f'{name} ({imode})'
                print(f'Using midi input device {name}')
                break

        self.binds = {}
        self.running = True
        self.done = False

    def bind(self, event, func):
        self.binds[event] = func

    def start(self, use_thread=True):
        def do_loop():
            while self.running:
                if self.midi_input and self.midi_input.poll():
                    [[[status, *params], timestamp]] = self.midi_input.read(1)
                    etype = status >> 4
                    channel = status & 0xf
                    event = self.events[etype] if etype in self.events else etype

                    if self.debug:
                        print(f'{self.midi_input.name}: {event} <{channel}>, {params} : {timestamp}')

                    if 'event' in self.binds:
                        self.binds['event'](event, channel, *params[:2])
                    if event in self.binds:
                        self.binds[event](channel, *params[:2])

            self.done = True

        if use_thread:
            mt = threading.Thread(target=do_loop)
            mt.start()
        else:
            do_loop()

    def end(self):
        self.running = False

        while not self.done:
            pass

        if self.midi_input:
            self.midi_input.close()