Develop Reference

How to record audio file using timer

Hi i am new for android and in my app i have to record audio using timer as like my below image, Using my below i can able record audio but how can do this scenario with help of timer please help me some
My code:-
#Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.record_button:
startRecording()
break;
case R.id.stop_button:
break;
}
}
private void startRecording() {
try {
mRecorder = new MediaRecorder();
mRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
mRecorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
mRecorder.setOutputFile(mFileName);
mRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
mRecorder.prepare();
mRecorder.start();
} catch (Throwable t) {
t.printStackTrace();
}
}
private void stopRecording() {
mRecorder.stop();
mRecorder.release();
mRecorder = null;
}

Just start a timer in startRecording and stop it in stopRecording. See: https://stackoverflow.com/a/3734070/2324204

You can use a Chronometer which already exists in Android.
Note: Chronometer is a widget that extends TextView so replace your current TextView with the Chronometer.
Example with your code would be:
//....
Chronometer simpleChronometer = (Chronometer) findViewById(R.id.simpleChronometer);
//...
private void startRecording() {
try {
mRecorder = new MediaRecorder();
mRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
mRecorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
mRecorder.setOutputFile(mFileName);
mRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
mRecorder.prepare();
mRecorder.start();
simpleChronometer.start(); // start a chronometer
//simpleChronometer.setFormat("Time Running - %s"); // set the format for a chronometer
} catch (Throwable t) {
t.printStackTrace();
}
}
private void stopRecording() {
mRecorder.stop();
mRecorder.release();
mRecorder = null;
simpleChronometer.stop();
}
In case you want to do things manually you can use the Stopwatch class.

android - How to know when user speaks into mic during a phone call

My goal is to be able to get a callback/hook when a user speaks into the mic during a phone call. I cant use RecognizerIntent.ACTION_RECOGNIZE_SPEECH because during a phone call this gets queued until the call ends then the prompt appears. I need something that while the user is on the phone i can determine if they speak into the mic. If there is no native way to do this, can you recommend a 3rd party ?
Right now im using android noiseAlert sample code and it looks like this:
public class SoundMeter {
static final private double EMA_FILTER = 0.6;
private MediaRecorder mRecorder = null;
private double mEMA = 0.0;
public void start() {
if (mRecorder == null) {
mRecorder = new MediaRecorder();
mRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
mRecorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
mRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
mRecorder.setOutputFile("/dev/null");
try {
mRecorder.prepare();
} catch (IOException e) {
e.printStackTrace();
}
mRecorder.start();
mEMA = 0.0;
}
}
public void stop() {
if (mRecorder != null) {
mRecorder.stop();
mRecorder.release();
mRecorder = null;
}
}
public double getAmplitude() {
if (mRecorder != null)
return (mRecorder.getMaxAmplitude()/2700.0);
else
return 0;
}
public double getAmplitudeEMA() {
double amp = getAmplitude();
mEMA = EMA_FILTER * amp + (1.0 - EMA_FILTER) * mEMA;
return mEMA;
}
}
What is a good measurement i can use to know that the user is speaking into the mic using this approach ? for Example can i do the following:
SoundMeter soundMeter = new SoundMeter();
soundMeter.start();
if(soundMeter.getAmplitude>1.0)
//users is talking into the mic

MediaPlayer get max aplitude

I want to implement a VU meter in my recording app when recording AND playing. I know how to do it when recording, but the problem appears when playing. How can I grab the max amplitude at a given point in time from android MediaPlayer? I know there is a way because I saw some widget that do the same when playing some music on my device. I don't want to use android Visualizer for rendering, I want to make my own VU meter to work for devices with OS 2.3+. Basically, I need getMaxAmplitude for MediaPlayer.

//first of all import this library
import android.media.MediaRecorder;
private MediaRecorder mRecorder = null;
public double getAmplitude() {
if (mRecorder != null)
return (mRecorder.getMaxAmplitude()/2700.0);
else
return 0;
}
//if you need further detail here is my class which is doing same thing
package com.spaidevelopers.noisealert;
import java.io.IOException;
import android.media.MediaRecorder;
public class SoundMeter {
// This file is used to record voice
static final private double EMA_FILTER = 0.6;
private MediaRecorder mRecorder = null;
private double mEMA = 0.0;
public void start() {
if (mRecorder == null) {
mRecorder = new MediaRecorder();
mRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
mRecorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
mRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
mRecorder.setOutputFile("/dev/null");
try {
mRecorder.prepare();
} catch (IllegalStateException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
mRecorder.start();
mEMA = 0.0;
}
}
public void stop() {
if (mRecorder != null) {
mRecorder.stop();
mRecorder.release();
mRecorder = null;
}
}
public double getAmplitude() {
if (mRecorder != null)
return (mRecorder.getMaxAmplitude()/2700.0);
else
return 0;
}
public double getAmplitudeEMA() {
double amp = getAmplitude();
mEMA = EMA_FILTER * amp + (1.0 - EMA_FILTER) * mEMA;
return mEMA;
}
}

How to change frequency of audio file and save it as mp4 file on sdcard?

I m trying to make an app where user can record his voice and can play the voice in funny tone. Like talking tom application but not just that..He shd be able to share that recorded sound file.
I m able to record the sound but not able to save the file in funny tone..its getting saved in original tone.
any suggestions?
private void startRecording() {
mFileName = Environment.getExternalStorageDirectory().getAbsolutePath();
mFileName += "/audiorecordtest.mp4";
mRecorder = new MediaRecorder();
mRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
mRecorder.setOutputFormat(MediaRecorder.OutputFormat.MPEG_4);
mRecorder.setOutputFile(mFileName);
mRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
try {
mRecorder.prepare();
} catch (IOException e) {
Log.e(LOG_TAG, "prepare() failed");
}
mRecorder.start();
}
private void stopRecording() {
mRecorder.stop();
mRecorder.release();
mRecorder = null;
}

Get microphone soundlevel in android

Im trying to get the sound level by getting live-input from the microphone.
As apps such as ,Sound meter and deciBel. I found this sample code from the link:
http://code.google.com/p/android-labs/source/browse/trunk/NoiseAlert/src/com/google/android/noisealert/SoundMeter.java
I'm also pasting it here.
package com.google.android.noisealert;
import android.media.MediaRecorder;
public class SoundMeter {
static final private double EMA_FILTER = 0.6;
private MediaRecorder mRecorder = null;
private double mEMA = 0.0;
public void start() {
if (mRecorder == null) {
mRecorder = new MediaRecorder();
mRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
mRecorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
mRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
mRecorder.setOutputFile("/dev/null");
mRecorder.prepare();
mRecorder.start();
mEMA = 0.0;
}
}
public void stop() {
if (mRecorder != null) {
mRecorder.stop();
mRecorder.release();
mRecorder = null;
}
}
public double getAmplitude() {
if (mRecorder != null)
return (mRecorder.getMaxAmplitude()/2700.0);
else
return 0;
}
public double getAmplitudeEMA() {
double amp = getAmplitude();
mEMA = EMA_FILTER * amp + (1.0 - EMA_FILTER) * mEMA;
return mEMA;
}
}
Does this code do what im trying to do?
Thanks!

it will once you:
instantiate the class
call its start() method
poll its getAmplitude() function from your main class (just as they did it in that sample code). Be aware that you need to do the polling in a Runnable() so that the UI is not affected. (Call the getAmplitude function every 100ms to detect a change in the input volume)
I have used it for that too and the code does the job.