Python program to sequence MIDI music using a CSV spreadsheet

music.csv

sheet_music.py

#!/usr/bin/env python3

import time
import csv
import mido

##############################################################################

def get_out_port(dev_name):
    out_port = None
    outputNames = mido.get_output_names()

    for outputName in outputNames:
        if dev_name in outputName.lower():
            print('Connecting to %s' % outputName)
            out_port = mido.open_output(outputName)
            break

    return out_port

bass_station = get_out_port("bass station")
drumbrute = get_out_port("drumbrute")

##############################################################################

MIDDLE_C = 60

# Semitone intervals for different scales
SCALE_INTERVS = {
    'major': [2, 2, 1, 2, 2, 2],
    'natural minor': [2, 1, 2, 2, 1, 2],
    'major pentatonic': [2, 2, 3, 2],
    'minor pentatonic': [3, 2, 2, 3],
    'blues': [3, 2, 1, 1, 3],
    'chromatic': [1, 1, 1, 1, 1, 1, 1, 1, 1, 1],
}

def gen_scale(root_note, scale, num_octaves=1):
    """
    Generate the notes of a scale based on a root note
    """

    # Get the intervals for this type of chord
    intervs = SCALE_INTERVS[scale]

    # List of generated notes
    notes = []

    # For each octave
    for oct_no in range(0, num_octaves):
        oct_root = root_note + 12 * oct_no

        # Add the root note to the scale
        notes.append(oct_root)

        # Add the scale notes
        for i in range(0, len(intervs)):
            prevNote = notes[-1]
            interv = intervs[i]
            notes.append(prevNote + interv)

    # Add the note closing the last octave
    notes.append(root_note + 12 * num_octaves)

    return notes

##############################################################################

scale = gen_scale(MIDDLE_C, 'natural minor')
print('scale:', scale)

def play_music():
    with open('music.csv', 'rt') as csvfile:
        reader = csv.reader(csvfile, delimiter=',', quotechar='"')
        rows = list(reader)

    for step_idx, row in enumerate(rows):
        if "kick" in row:
            drumbrute.send(mido.Message('note_on', note=36, velocity=127, channel=1))
        if "snare" in row:
            drumbrute.send(mido.Message('note_on', note=38, velocity=127, channel=1))
        if "clap" in row:
            drumbrute.send(mido.Message('note_on', note=39, velocity=127, channel=1))
        if "hat" in row:
            drumbrute.send(mido.Message('note_on', note=42, velocity=127, channel=1))

        note_no = None
        if "X" in row:
            degree = row.index("X")
            note_no = scale[degree]

        if note_no:
            note_no = scale[degree]
            bass_station.send(mido.Message('note_on', velocity=127, note=note_no))

        time.sleep(0.07)

        if note_no:
            bass_station.send(mido.Message('note_off', velocity=127, note=note_no))

        time.sleep(0.05)

try:
    while True:
        play_music()
except KeyboardInterrupt:
    # Send all-notes-off message
    bass_station.reset()