audio: handle looping and large file playback better.

[Gadgetoid]

• Stops large files from crashing my Pico, since anything >10k would fail to write audio data on callback
• Special case looped playback to fill a whole buffer with copies of the wav file, ensures a gapless loop (in theory)
• Implement a WavReader class to abstract away the nuances of offset and data length (avoid playing metadata as audio)
• Add a deinit() method to WavPlayer which MUST be called to avoid hard crashes on soft resets

Examples:

import os
import time
from tiny_fx import TinyFX
from audio_new import WavPlayer
import random

wav = WavPlayer(0, TinyFX.I2S_BCLK, TinyFX.I2S_LRCLK, TinyFX.I2S_DATA, amp_enable=TinyFX.AMP_EN_PIN, root="/")

wav.play_wav("440Hz_44100Hz_16bit_05sec.wav", loop=True)

try:
    while True:
        time.sleep(1.0)
        print(wav._loop_count)
finally:
    wav.deinit()

Single shot playback:

import os
import time
from tiny_fx import TinyFX
from audio_new import WavPlayer
import random

wav = WavPlayer(0, TinyFX.I2S_BCLK, TinyFX.I2S_LRCLK, TinyFX.I2S_DATA, amp_enable=TinyFX.AMP_EN_PIN, root="/sounds")

files = os.listdir("/sounds")

try:
    while True:
        file = random.choice(files)
        wav.play_wav(file)
        print(f"Playing: {file}")
        while wav.is_playing():
            time.sleep(0.1)
        print("done!")
        time.sleep(0.5)
except KeyboardInterrupt:
    pass
finally:
    wav.deinit()

[Gadgetoid]

Demo for wave shapes:

import os
import time
from tiny_fx import TinyFX
from audio import WavPlayer
import random

wav = WavPlayer(0, TinyFX.I2S_BCLK, TinyFX.I2S_LRCLK, TinyFX.I2S_DATA, amp_enable=TinyFX.AMP_EN_PIN)
tinyfx = TinyFX()

tones = [440, 440, 440, 0]
durations = [1.0, 1.0, 1.0, 2.0]
shapes = [wav.TONE_SINE, wav.TONE_SQUARE, wav.TONE_TRIANGLE, 0]
leds = [1, 2, 3, 0]

n = 0

try:
    while True:
        tone = tones[n]
        duration = durations[n]
        shape = shapes[n]
        led = leds[n]
        if tone:
            wav.play_tone(tone, 1.0, shape)
        tinyfx.clear()
        if led:
            tinyfx.outputs[led - 1].on()
        time.sleep(duration)
        wav.stop()
        time.sleep(0.1)
        n += 1
        n %= len(tones)
except KeyboardInterrupt:
    pass
finally:
    wav.deinit()