How to set the speed of mid.play()

[yk0n9]

I want to control the sending speed of mid.play, for example, 1.5x, 2x

[rdoursenaud]

The play method from the mido.MidiFile class is pretty straightforward:

def play(self, meta_messages=False):
    """Play back all tracks.

    The generator will sleep between each message by
    default. Messages are yielded with correct timing. The time
    attribute is set to the number of seconds slept since the
    previous message.

    By default you will only get normal MIDI messages. Pass
    meta_messages=True if you also want meta messages.

    You will receive copies of the original messages, so you can
    safely modify them without ruining the tracks.
    """
    start_time = time.time()
    input_time = 0.0

    for msg in self:
        input_time += msg.time

        playback_time = time.time() - start_time
        duration_to_next_event = input_time - playback_time

        if duration_to_next_event > 0.0:
            time.sleep(duration_to_next_event)

        if isinstance(msg, MetaMessage) and not meta_messages:
            continue
        else:
            yield msg

One way to do it would be to override it in your own subclass:

class MyMidiFile(mido.MidiFile):
    def play(self, meta_messages=False, speed=1):
        """Play back all tracks.

        The generator will sleep between each message by
        default. Messages are yielded with correct timing. The time
        attribute is set to the number of seconds slept since the
        previous message.

        By default you will only get normal MIDI messages. Pass
        meta_messages=True if you also want meta messages.

        You will receive copies of the original messages, so you can
        safely modify them without ruining the tracks.
        """
        start_time = time.time()
        input_time = 0.0

        for msg in self:
            input_time += msg.time * speed

            playback_time = time.time() - start_time
            duration_to_next_event = input_time - playback_time

            if duration_to_next_event > 0.0:
                time.sleep(duration_to_next_event)

            if isinstance(msg, MetaMessage) and not meta_messages:
                continue
            else:
                yield msg