Android Flashlight blinking at rythm of the (output) music

Implementing the Android class Visualizer to synchronize the flashlight with the output music is definitely doable. Here is a high-level overview of the steps you can take to implement this feature:

1:Request Audio Permission: To use the Visualizer class, you need to request permission from the user to access the microphone. Add the following line to your AndroidManifest.xml file:

<uses-permission android:name="android.permission.RECORD_AUDIO" />

 

2:Create an instance of the Visualizer class: In your activity's onCreate method, create an instance of the Visualizer class and set its capture size and the listener for the waveform:

int captureSize = Visualizer.getCaptureSizeRange()[1];
Visualizer visualizer = new Visualizer(0);
visualizer.setCaptureSize(captureSize);
visualizer.setDataCaptureListener(new Visualizer.OnDataCaptureListener() {
    @Override
    public void onWaveFormDataCapture(Visualizer visualizer, byte[] waveform, int samplingRate) {
        // This method will be called periodically with the waveform data.
        // You can use this data to synchronize the flashlight with the output music.
    }

    @Override
    public void onFftDataCapture(Visualizer visualizer, byte[] fft, int samplingRate) {
        // This method will be called periodically with the FFT data.
        // You can use this data to synchronize the flashlight with the output music.
    }
}, Visualizer.getMaxCaptureRate() / 2, true, false);
visualizer.setEnabled(true);
 

3:Synchronize the flashlight with the music: In the onWaveFormDataCapture or onFftDataCapture methods, you can use the waveform or FFT data to synchronize the flashlight with the output music. You can use the same approach as in your existing code to turn the flashlight on and off at a regular interval, but adjust the interval based on the music data to synchronize the flashing with the beat of the music.

// Example implementation in onWaveFormDataCapture method
for (int i = 0; i < waveform.length; i++) {
    if (waveform[i] < 0) {
        setFlashOn(true);
    } else {
        setFlashOn(false);
    }
    try {
        Thread.sleep(interval);
    } catch (InterruptedException e) {
        e.printStackTrace();
    }
}

Clean up: In your activity's onDestroy method, release the Visualizer instance:

visualizer.setEnabled(false);
visualizer.release();
 

Note that the above implementation is just an example, and there are many ways to synchronize the flashlight with the music. You can experiment with different approaches to find the one that works best for your app.