Send real-time PCM audio (16-bit integer) to your device speakers, from your Flutter app! Note: This is a fork of flutter_pcm_sound with the following changes:

• Added support for Web
• Support for clearing buffer (to remove pending audio from the playback buffer)
• Fade out support (to stop audio playback smoothly)
• Clear buffer support (to remove pending audio from the playback buffer)

No Dependencies

FlutterPcmSound has zero dependencies besides Flutter, Android, iOS, Web, and MacOS themselves.

Not for Audio Files

Unlike other plugins, flutter_pcm_sound does not use audio files (For example: sound_pool).

Instead, flutter_pcm_sound is for apps that generate audio in realtime a few milliseconds before you hear it. For example, using dart_melty_soundfont.

Callback Based, For Real-Time Audio

In contrast to raw_sound, FlutterPcmSound uses a callback setFeedCallback to signal when to feed more samples.

You can lower the feed threshold using setFeedThreshold to achieve real time audio, or increase it to have a cushy buffer.

One-Pedal Driving

To play audio, just keep calling feed.

To stop audio, just stop calling feed.

Clearing Buffer

To clear the buffer, call clearBuffer.

Usage

// for testing purposes, a C-Major scale
MajorScale scale = MajorScale(sampleRate: 44100, noteDuration: 0.25);

// invoked whenever we need to feed more samples to the platform
void onFeed(int remainingFrames) async {
    // you could use 'remainingFrames' to feed very precisely.
    // But here we just load a few thousand samples everytime we run low.
    List<int> frame = scale.generate(periods: 20);
    await FlutterPcmSound.feed(PcmArrayInt16.fromList(frame));
}

await FlutterPcmSound.setup(sampleRate: 44100, channelCount: 1);
await FlutterPcmSound.setFeedThreshold(8000);
FlutterPcmSound.setFeedCallback(onFeed);
FlutterPcmSound.start(); // for convenience. Equivalent to calling onFeed(0);
await FlutterPcmSound.clearBuffer();

⭐ Stars ⭐

Please star this repo & on pub.dev. We all benefit from having a larger community.

Acknowledgments

Thanks to chipweinberger for the original flutter_pcm_sound package.