clean_pitch_bend.py

import mido
import sys

def clean_pitch_bend(input_path, output_path):
    mid = mido.MidiFile(input_path)
    last_pb = {}
    
    for track in mid.tracks:
        new_events = []
        delay_acculm = {i: 0 for i in range(16)}
        for msg in track:
            if isinstance(msg, mido.Message) and msg.type != "sysex":
                channel = msg.channel
                if msg.is_cc(10) and msg.value == 63:
                    # BENDY (the plugin I use to generate pitch bends in FL)
                    # sabotages panning like this for some reason
                    msg.value += 1
                elif msg.type == "pitchwheel":
                    target_pb = last_pb.get(channel, None)
                    if target_pb is not None and target_pb.pitch == msg.pitch:
                        delay_acculm[channel] += msg.time
                        continue
                    print(msg.pitch, str(target_pb))
                    last_pb[channel] = msg
                if delay_acculm.get(channel, None) > 0:
                    msg.time += delay_acculm[channel]
                    delay_acculm[channel] = 0
            new_events.append(msg)
        track[:] = new_events

    mid.save(output_path)

clean_pitch_bend(sys.argv[1], sys.argv[2])