Music Lights

#!/usr/bin/env python3
"""Show a text-mode spectrogram using live microphone data."""
import argparse
import math
import shutil

import numpy as np
import sounddevice as sd

from gpiozero import LEDBoard

# Init with numbers of the GPIO pins
leds = LEDBoard(5, 6, 13, 19, 26, 21, 20, 16, 12, 1, pwm=True)

usage_line = ' press <enter> to quit, +<enter> or -<enter> to change scaling '

def int_or_str(text):
    """Helper function for argument parsing."""
    try:
        return int(text)
    except ValueError:
        return text

# Number of LEDs, param can be used to override
columns = 10

parser = argparse.ArgumentParser(add_help=False)
parser.add_argument(
    '-l', '--list-devices', action='store_true',
    help='show list of audio devices and exit')
args, remaining = parser.parse_known_args()
if args.list_devices:
    print(sd.query_devices())
    parser.exit(0)
parser = argparse.ArgumentParser(
    description=__doc__ + '\n\nSupported keys:' + usage_line,
    formatter_class=argparse.RawDescriptionHelpFormatter,
    parents=[parser])
parser.add_argument(
    '-b', '--block-duration', type=float, metavar='DURATION', default=50,
    help='block size (default %(default)s milliseconds)')
parser.add_argument(
    '-c', '--columns', type=int, default=columns,
    help='width of spectrogram')
parser.add_argument(
    '-d', '--device', type=int_or_str,
    help='input device (numeric ID or substring)')
parser.add_argument(
    '-g', '--gain', type=float, default=10,
    help='initial gain factor (default %(default)s)')
parser.add_argument(
    '-r', '--range', type=float, nargs=2,
    metavar=('LOW', 'HIGH'), default=[100, 2000],
    help='frequency range (default %(default)s Hz)')
args = parser.parse_args(remaining)

low, high = args.range
if high <= low:
    parser.error('HIGH must be greater than LOW')

try:
    samplerate = sd.query_devices(args.device, 'input')['default_samplerate']

    delta_f = (high - low) / (args.columns - 1)
    fftsize = math.ceil(samplerate / delta_f)
    low_bin = math.floor(low / delta_f)

    def callback(indata, frames, time, status):
        if status:
            text = ' ' + str(status) + ' '
            print('\x1b[34;40m', text.center(args.columns, '#'),
                  '\x1b[0m', sep='')
        if any(indata):
            magnitude = np.abs(np.fft.rfft(indata[:, 0], n=fftsize))
            magnitude *= args.gain / fftsize
            # set new brightness for the LEDs
            leds.value = np.clip(magnitude[low_bin:low_bin + args.columns], 0, 1)
        else:
            print('no input')

    with sd.InputStream(device=args.device, channels=1, callback=callback,
                        blocksize=int(samplerate * args.block_duration / 1000),
                        samplerate=samplerate):
        while True:
            response = input()
            if response in ('', 'q', 'Q'):
                break
            for ch in response:
                if ch == '+':
                    args.gain *= 2
                elif ch == '-':
                    args.gain /= 2
                else:
                    print('\x1b[31;40m', usage_line.center(args.columns, '#'),
                          '\x1b[0m', sep='')
                    break

except KeyboardInterrupt:
    parser.exit('Interrupted by user')
except Exception as e:
    parser.exit(type(e).__name__ + ': ' + str(e))