I want to check the volume of voice in android

Question

I am developing an application where I have to detect voice volume. Means some of the screams on a mobile phone and it will show the volume level on the screen.

What API can be used for this?

Answer 1

Take a look at http://developer.android.com/reference/android/media/AudioRecord.html

When you read the buffer, byte values ​​will represent the amplitude. The higher the byte value, the louder the sound.

Here is a smaller version of what I used in an application that I wrote some time ago:

Add this to your mainifest.xml
<uses-permission android:name="android.permission.RECORD_AUDIO" />

soundlevel.xml

 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent" android:orientation="vertical" > <ToggleButton android:id="@+id/togglebutton_record" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="ToggleButton" /> <ProgressBar android:id="@+id/progressbar_level" style="?android:attr/progressBarStyleHorizontal" android:layout_width="match_parent" android:layout_height="wrap_content" /> </LinearLayout> 

SoundLevel.java

 import android.app.Activity; import android.media.AudioFormat; import android.media.AudioRecord; import android.media.MediaRecorder; import android.os.Bundle; import android.os.Handler; import android.os.SystemClock; import android.widget.CompoundButton; import android.widget.ProgressBar; import android.widget.ToggleButton; public class SoundLevel extends Activity { private static final int sampleRate = 11025; private static final int bufferSizeFactor = 10; private AudioRecord audio; private int bufferSize; private ProgressBar level; private Handler handler = new Handler(); private int lastLevel = 0; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.soundlevel); level = (ProgressBar) findViewById(R.id.progressbar_level); level.setMax(32676); ToggleButton record = (ToggleButton) findViewById(R.id.togglebutton_record); record.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() { public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) { // TODO Auto-generated method stub if (isChecked) { bufferSize = AudioRecord.getMinBufferSize(sampleRate, AudioFormat.CHANNEL_CONFIGURATION_MONO, AudioFormat.ENCODING_PCM_16BIT) * bufferSizeFactor; audio = new AudioRecord(MediaRecorder.AudioSource.MIC, sampleRate, AudioFormat.CHANNEL_CONFIGURATION_MONO, AudioFormat.ENCODING_PCM_16BIT, bufferSize); audio.startRecording(); Thread thread = new Thread(new Runnable() { public void run() { readAudioBuffer(); } }); thread.setPriority(Thread.currentThread().getThreadGroup().getMaxPriority()); thread.start(); handler.removeCallbacks(update); handler.postDelayed(update, 25); } else if (audio != null) { audio.stop(); audio.release(); audio = null; handler.removeCallbacks(update); } } }); } private void readAudioBuffer() { try { short[] buffer = new short[bufferSize]; int bufferReadResult; do { bufferReadResult = audio.read(buffer, 0, bufferSize); for (int i = 0; i < bufferReadResult; i++){ if (buffer[i] > lastLevel) { lastLevel = buffer[i]; } } } while (bufferReadResult > 0 && audio.getRecordingState() == AudioRecord.RECORDSTATE_RECORDING); if (audio != null) { audio.release(); audio = null; handler.removeCallbacks(update); } } catch (Exception e) { e.printStackTrace(); } } private Runnable update = new Runnable() { public void run() { SoundLevel.this.level.setProgress(lastLevel); lastLevel *= .5; handler.postAtTime(this, SystemClock.uptimeMillis() + 500); } }; }