Raspberry Pi Bluetooth Audio LED (with ws281x)

aled.py

#!/usr/bin/python3

import colorsys
import subprocess
import traceback
import math

import numpy as np
from rpi_ws281x import Color, PixelStrip

# LED Configuration
LED_COUNT = 60
GPIO_PIN = 18

# LED2_COUNT = 15
# GPIO_PIN2 = 13

LOOP_PERIOD = 4500
HUE_DIVISION = 50 * 60

# Start the audio process
ffmpeg = subprocess.Popen(
    'ffmpeg -loglevel warning -f alsa -i bluealsa -f s16le -ac 1 -ar 16000 - -f alsa default',
    stdout=subprocess.PIPE,
    shell=True)

# LED initialization
strip = PixelStrip(LED_COUNT, GPIO_PIN, 800000, 10, False, 255, 0)
# strip2 = PixelStrip(LED2_COUNT, GPIO_PIN2, 800000, 11, False, 255, 1)

strip.begin()
# strip2.begin()

# Set up variables
ratio = 0
zero = Color(0, 0, 0)

print('init')
try:
    while True:

        # Get samples
        buffer = ffmpeg.stdout.read(160 * 2)
        wave = np.abs(np.frombuffer(buffer, dtype=np.int16))
        ratio = max((np.max(wave) / 32768)**0.5,
                    ratio - 0.02)  # Normalize to [0,1]

        # Get color
        colorarr = colorsys.hsv_to_rgb(max(0.9 - ratio, 0), 1, 1)
        color = Color(int(colorarr[0] * 255), int(colorarr[1] * 255),
                      int(colorarr[2] * 255))

        # Flip
        for j in range(LED_COUNT):
            if j < LED_COUNT * ratio:
                strip.setPixelColor(j, color)
            else:
                strip.setPixelColor(j, zero)

        strip.show()
except:
    traceback.print_exc()
    print(ratio, color)
finally:

    # Turn off the LED
    for i in range(LED_COUNT):
        strip.setPixelColor(i, zero)
    strip.show()