spectroshaker/code.py

"""
Spectroshaker by The Dod:
Adafruit CircuitPlayground Bluefruit dual-mode "bling"
(selectable via the slider switch).
The RGB levels of neopixels around the circuit indicate:
- Low/Mid/High sound levels (spectrogram mode)
- X/Y/Z acceleration (shaker mode)
TO BE CONTINUED ...
"""
import math
import time
from adafruit_circuitplayground import cp
from teaandtechtime_fft import spectrogram

NUM_PIXELS = 10
# Like a clock, with connectors at 12 (USB) and 6 (power)
LED_ANGLES = [
    i*math.pi/6.0
    for i in [11, 10, 9, 8, 7, 5, 4, 3, 2, 1]]

minx = miny = minz = -5.0
maxx = maxy = maxz = 5.0

fft_size = 8 # power of 2
samples = [0.0+0.0j]*fft_size
MAX_2FREQ = 10.0 # After testing this a bit in the wild

cp.pixels.brightness = 0.1

def angles2level(led, val):
    led_angle = LED_ANGLES[led]
    val_angle = val * 2.0 * math.pi
    angle = led_angle - val_angle
    while angle>2*math.pi:
        angle -= 2*math.pi
    # the pow() makes sin() values sharper
    return int(255*pow(math.sin(angle/2), 4))

while True:
    if cp.button_a:
        cp.pixels.brightness = max(0.05, cp.pixels.brightness*0.9)
    elif cp.button_b:
        cp.pixels.brightness = min(0.95, 1.0-(1.0-cp.pixels.brightness)*0.9)

    samples.pop(0)
    samples.append(cp.sound_level+0.0j)
    x, y, z = cp.acceleration
    if x<minx: minx = x
    if y<miny: miny = y
    if z<minz: minz = z
    if x>maxx: maxx = x
    if y>maxy: maxy = y
    if z>maxx: maxz = z
    if cp.switch: # accelerometer mode
        vals = (
            (x-minx)/(maxx-minx),
            (y-miny)/(maxy-miny),
            (z-minz)/(maxz-minz))
    else: # spectrogram mode
        raw_freqs = spectrogram(samples)
        pairs = [raw_freqs[i]+raw_freqs[i+1] for i in range(fft_size//2)]
        vals = [min(1.0, abs(x/MAX_2FREQ)) for x in pairs[:3]]
    for i in range(NUM_PIXELS):
        cp.pixels[i] = (
            angles2level(i, vals[0]),
            angles2level(i, vals[1]),
            angles2level(i, vals[2]))
    time.sleep(0.01)