PianoTeqnician.py

#!/usr/bin/env python3

"""
PianoTeqnician

Reroute MIDI events to two instances of Pianoteq to circumvent the free trial
limitation on certain keys. All enabled keys are routed to one normal instance
of Pianoteq, and the disabled ones are routed to another instance, but shifted
one semitone down. Then, on that other instance of Pianoteq, tune the piano to
466 Hz to restore the pitch of the shifted notes.

Requires JACK and Catia (or any other JACK patchbays) to route the MIDI data
to the right instances of Pianoteq.

python3 -m pip install JACK-Client
"""

import jack
import struct
import binascii

# First 4 bits of status byte:
NOTEON = 0x9
NOTEOFF = 0x8
CHANCTRL = 0xb

muted = [42, 44, 46, 85, 87, 90, 92, 94]

client = jack.Client('PianoTeqnician')
inport = client.midi_inports.register('input')
out_normal = client.midi_outports.register('normal_output')
out_muted = client.midi_outports.register('muted_output')

@client.set_process_callback
def process(frames):
    out_normal.clear_buffer()
    out_muted.clear_buffer()
    for offset, indata in inport.incoming_midi_events():
        try:
            out_normal.write_midi_event(offset, indata)
        except:
            pass

        # notes
        if len(indata) == 3:
            status, pitch, vel = struct.unpack('3B', indata)
            try:
                if status >> 4 in (NOTEON, NOTEOFF) and pitch in muted:
                    out_muted.write_midi_event(offset, (status, pitch - 1, vel))
                elif status >> 4 == CHANCTRL:
                    out_muted.write_midi_event(offset, indata)
            except:
                pass

with client:
    print('#' * 80)
    print('press Return to quit')
    print('#' * 80)
    input()