TarsosDSP

README.md

For API level < 23, don't forget to add the correct permissions to the manifest:

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

For API level > 23, the check needs to be done at runtime (see Activity.java)

Good introduction to sound analysis with TarsosDSP

Activity.java

package com.example.admin.sound;

import android.Manifest;
import android.content.pm.PackageManager;
import android.os.Build;
import android.support.v4.app.ActivityCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.widget.TextView;

import be.tarsos.dsp.AudioDispatcher;
import be.tarsos.dsp.AudioEvent;
import be.tarsos.dsp.AudioProcessor;
import be.tarsos.dsp.io.android.AudioDispatcherFactory;
import be.tarsos.dsp.pitch.PitchDetectionHandler;
import be.tarsos.dsp.pitch.PitchDetectionResult;
import be.tarsos.dsp.pitch.PitchProcessor;

public class Activity extends AppCompatActivity {

    private final static String TAG = "SOUND";

    private AudioDispatcher dispatcher;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        requestRecordAudioPermission();

        dispatcher = AudioDispatcherFactory.fromDefaultMicrophone(22050, 1024, 0);

        AudioProcessor soundPressureProcessor = new AudioProcessor() {
            @Override
            public boolean process(AudioEvent audioEvent) {
                float[] buffer = audioEvent.getFloatBuffer();

                double power = 0.0;

                for (float el : buffer) {
                    power += el * el;
                }

                double value = Math.pow(power, 0.5) / buffer.length;

                final double pressure = 20.0 * Math.log10(value);

                runOnUiThread(new Runnable() {
                    @Override
                    public void run() {
                        TextView text = (TextView) findViewById(R.id.pressure);
                        text.setText(String.valueOf(pressure) + "Db");
                    }
                });

                return true;
            }

            @Override
            public void processingFinished() {

            }
        };

        dispatcher.addAudioProcessor(soundPressureProcessor);

        PitchDetectionHandler pitchDetection = new PitchDetectionHandler() {
            @Override
            public void handlePitch(PitchDetectionResult pitchDetectionResult, AudioEvent audioEvent) {
                final float pitch = pitchDetectionResult.getPitch();
                runOnUiThread(new Runnable() {
                    @Override
                    public void run() {
                        TextView text = (TextView) findViewById(R.id.pitch);
                        text.setText(String.valueOf(pitch) + "Hz");
                    }
                });
            }
        };

        AudioProcessor pitchProcessor = new PitchProcessor(PitchProcessor.PitchEstimationAlgorithm.FFT_YIN, 22050, 1024, pitchDetection);

        dispatcher.addAudioProcessor(pitchProcessor);

        new Thread(dispatcher, "Dispatcher").start();
    }

    // see https://developer.android.com/training/permissions/requesting.html
    private void requestRecordAudioPermission() {
        int apiVersion = Build.VERSION.SDK_INT;

        if (apiVersion > Build.VERSION_CODES.LOLLIPOP) {
            ActivityCompat.requestPermissions(this, new String[] {Manifest.permission.RECORD_AUDIO}, 1);
        }
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, String permissions[], int[] grantResults) {
        switch (requestCode) {
            case 1: {
                if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                    Log.d(TAG, "Permission granted");
                }
                else {
                    Log.d(TAG, "Permission denied");
                    finish();
                }
            }
        }
    }
}