AudioFileSourceSD playback buffering and crashing #642
Description
Hello, I am using the ESP32 to play some sounds from an SD card.
When the files are smaller that the buffer size, the playback is fine, but if a file is longer that the buffer size, there is stuttering for loading the next buffer and crashes after a bit. I have tried to:
- up the buffer size, but there is a limit to RAM and I don't want to go to the external RAM route
- up the read speed of the SD card, this helped but it was not enough to completely remove the stuttering
- use the AudioFIleSourceBuffer class with double the buffer size, with no changes to performance
Is there a better way to avoid the problem without adding external RAM to my project?
Here is part of the code that handles audio playback:
#define SD_CARD_PIN 26
#define AUDIO_BUFFER_SIZE 48000
AudioGeneratorWAV *wav = nullptr;
AudioFileSourceSD *file = nullptr;
AudioFileSourceBuffer *fileBuffer = nullptr;
AudioOutputI2S *out = nullptr;
void beginFile(char * targetPath)
{
if (!SD.exists(targetPath))
{
Serial.printf("File does not exist: %s\n", targetPath);
return;
}
file->open(targetPath);
wav->begin(fileBuffer, out);
}
void setup()
{
Serial.begin(115200);
audioLogger = &Serial;
delay(1000);
if (!SD.begin(SD_CARD_PIN, SPI, 0x0fffffff))
logAndAbort("Failed to initialize SD card");
SD.open("/");
out = new AudioOutputI2S(0, 1);
wav = new AudioGeneratorWAV();
wav->SetBufferSize(AUDIO_BUFFER_SIZE);
file = new AudioFileSourceSD();
fileBuffer = new AudioFileSourceBuffer(file, 2 * AUDIO_BUFFER_SIZE);
}
void loop()
{
if (wav->isRunning() && !wav->loop())
stopCurrentFile();
if (digitalRead(BUTTON) == 0)
beginFile("/myfile.wav");
}