Adafruit_CircuitPython_Circ.../examples/circuitplayground_sound_meter.py
2019-06-07 14:45:09 -04:00

56 lines
1.8 KiB
Python

"""This example uses the sound sensor, located next to the picture of the ear on your board, to
light up the NeoPixels as a sound meter. Try talking to your CPX or clapping, etc, to see the
NeoPixels light up!"""
import array
import math
import audiobusio
import board
from adafruit_circuitplayground.express import cpx
def constrain(value, floor, ceiling):
return max(floor, min(value, ceiling))
def log_scale(input_value, input_min, input_max, output_min, output_max):
normalized_input_value = (input_value - input_min) / (input_max - input_min)
return output_min + math.pow(normalized_input_value, 0.630957) * (output_max - output_min)
def normalized_rms(values):
minbuf = int(sum(values) / len(values))
return math.sqrt(sum(float(sample - minbuf) *
(sample - minbuf) for sample in values) / len(values))
mic = audiobusio.PDMIn(board.MICROPHONE_CLOCK, board.MICROPHONE_DATA,
sample_rate=16000, bit_depth=16)
samples = array.array('H', [0] * 160)
mic.record(samples, len(samples))
input_floor = normalized_rms(samples) + 10
# Lower number means more sensitive - more LEDs will light up with less sound.
sensitivity = 500
input_ceiling = input_floor + sensitivity
peak = 0
while True:
mic.record(samples, len(samples))
magnitude = normalized_rms(samples)
print((magnitude,))
c = log_scale(constrain(magnitude, input_floor, input_ceiling),
input_floor, input_ceiling, 0, 10)
cpx.pixels.fill((0, 0, 0))
for i in range(10):
if i < c:
cpx.pixels[i] = (i * (255 // 10), 50, 0)
if c >= peak:
peak = min(c, 10 - 1)
elif peak > 0:
peak = peak - 1
if peak > 0:
cpx.pixels[int(peak)] = (80, 0, 255)
cpx.pixels.show()