jack midi python script 2 invert midi pedal messages !!!!! (on -> off, off -> on)

pedal_reverse.py

#!/usr/bin/env python3

"""JACK client that inverts pedal mapping."""

import jack
import struct
import threading

client = jack.Client("invert pedal")
port_input  = client.midi_inports.register("input")
port_output = client.midi_outports.register("output")

@client.set_process_callback
def process(frames):
    port_output.clear_buffer()
    for offset, data in port_input.incoming_midi_events():
        if len(data) == 3:
            status, controller, value = struct.unpack('3B', data)
            if status >> 4 == 0xb and controller == 0x40:
                port_output.write_midi_event(offset, (status, controller, 0x7f - value))
                continue
        port_output.write_midi_event(offset, data)

with client:
    threading.Event().wait()