ambient noise generator

code.py

# SPDX-FileCopyrightText: 2023 John Park
#
# SPDX-License-Identifier: MIT
# Ambient Machine inspired by Yuri Suzuki https://www.yurisuzuki.com/projects/the-ambient-machine
import os
import gc
import board
import audiocore
import audiobusio
import audiomixer
from digitalio import Pull
import audiopwmio
import time
from random import randint

wav_files = []

num_samples = 0
for filename in os.listdir('/samples/'):  # on board flash
    if filename.lower().endswith('.wav') and not filename.startswith('.'):
        wav_files.append("/samples/"+filename)
        print(filename)
        num_samples += 1

wav_files.sort()  # put in alphabetical/numberical order
gc.collect()

#audio = audiobusio.I2SOut(bit_clock=bck_pin, word_select=lck_pin, data=dat_pin)
audio = audiopwmio.PWMAudioOut(board.A1)

mixer = audiomixer.Mixer(voice_count=len(wav_files), sample_rate=22050, channel_count=1,
                         bits_per_sample=16, samples_signed=True, buffer_size=2048)
                         
audio.play(mixer)

for i in range(num_samples):  # start playing all wavs on loop w levels down
    wave = audiocore.WaveFile(wav_files[i], bytearray(1024))
    mixer.voice[i].play(wave, loop=True)
    mixer.voice[i].level = 0.0

LOW_VOL = 0.2
HIGH_VOL = 0.5

mixer.voice[2].level = 0.2

MIXER_MAX_LEVEL=0.1

size_lfo_1 = 100
size_lfo_2 = 250
size_lfo_3 = 450

wave_table_1 = []
wave_table_2 = []
wave_table_3 = []

def fill_wave_table(wave_table, size):
    wave_table[:] = []
    for i in range(size/2):
        wave_table.append(1/(size/2)*i)
        
        
    for i in range(size/2):
        wave_table.append(1-(1/(size/2)*i))

        
fill_wave_table(wave_table_1, size_lfo_1)
fill_wave_table(wave_table_2, size_lfo_2)
fill_wave_table(wave_table_3, size_lfo_3)

print(wave_table_1)

counter_vol_1 = 0
counter_vol_2 = 0
counter_vol_3 = 0

lfo_1_voice = 1
lfo_2_voice = 2
lfo_3_voice = 3

while True:
    time.sleep(0.1)
    mixer.voice[lfo_1_voice].level = wave_table_1[counter_vol_1]* MIXER_MAX_LEVEL
    counter_vol_1 += 1
    if counter_vol_1 == size_lfo_1:
        counter_vol_1 = 0
        lfo_1_voice = randint(0,num_samples-1)
        print("new voice: ", lfo_1_voice)
    mixer.voice[lfo_2_voice].level = wave_table_2[counter_vol_2]* MIXER_MAX_LEVEL
    counter_vol_2 += 1
    if counter_vol_2 == size_lfo_2:
        counter_vol_2 = 0
        lfo_2_voice = randint(0,num_samples-1)
    mixer.voice[lfo_3_voice].level = wave_table_3[counter_vol_3]* MIXER_MAX_LEVEL
    counter_vol_3 += 1
    if counter_vol_3 == size_lfo_3:
        counter_vol_3 = 0
        lfo_3_voice = randint(0,num_samples-1)