Send real-time PCM audio (16-bit integer) to your device speakers, from your Flutter app!

No Dependencies

FlutterPcmSound has zero dependencies besides Flutter, Android, iOS, 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.

You can also manually feed whenever you like.

ignore feed threshold

To monitor remaining samples in real-time, you can use setFeedThreshold(-1).

We will invoke your callback 30-100 times per second regardless of how many samples remain.

iOS is a stable ~100htz.

Android is less predictable. Figure around ~30-60htz.

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: 100);
    await FlutterPcmSound.feed(PcmArrayInt16.fromList(frame));
}

await FlutterPcmSound.setup(sampleRate: 44100, channelCount: 1);
await FlutterPcmSound.setFeedThreshold(8000); // feed when below 8000 queued frames
await FlutterPcmSound.setFeedCallback(onFeed);
await FlutterPcmSound.play();

Other Functions

// clears all queued samples
await FlutterPcmSound.clear();

// suspend playback & clear queued samples
await FlutterPcmSound.stop(clear: true);

// get the current number of queued frames
int samples = await FlutterPcmSound.remainingFrames();

⭐ Stars ⭐

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

Example App

Enable the platforms you need.

cd ./example                      
flutter config --enable-macos-desktop                                                      
flutter config --enable-android 
flutter config --enable-ios 
flutter create .
flutter run