Develop Reference

How to record audio with different frequency?

I am trying to record audio with different frequency. Though I have been trying to implement it by the following code but its not working (app unexpectedly stopped).
//importing packages
import android.app.Activity;
import android.media.AudioFormat;
import android.media.AudioRecord;
import android.media.MediaRecorder;
import android.os.Bundle;
import android.os.Environment;
import android.view.KeyEvent;
import android.view.View;
import android.widget.Button;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
public class MainActivity extends Activity {
private static final int RECORDER_SAMPLERATE = 44100;
private static final int RECORDER_CHANNELS = AudioFormat.CHANNEL_IN_MONO;
private static final int RECORDER_AUDIO_ENCODING = AudioFormat.ENCODING_PCM_16BIT;
private AudioRecord recorder = null;
private Thread recordingThread = null;
private boolean isRecording = false;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
setButtonHandlers();//handling buttons
enableButtons(false);
int bufferSize = AudioRecord.getMinBufferSize(RECORDER_SAMPLERATE,
RECORDER_CHANNELS, RECORDER_AUDIO_ENCODING);
}
private void setButtonHandlers() {
((Button) findViewById(R.id.Start)).setOnClickListener(btnClick);
((Button) findViewById(R.id.Stop)).setOnClickListener(btnClick);
}
private void enableButton(int id, boolean isEnable) {
((Button) findViewById(id)).setEnabled(isEnable);
}
private void enableButtons(boolean isRecording) {
enableButton(R.id.Start, !isRecording);
enableButton(R.id.Stop, isRecording);
}
int BufferElements2Rec = 1024; // want to play 2048 (2K) since 2 bytes we use only 1024
int BytesPerElement = 2; // 2 bytes in 16bit format
public void Record()
{
recorder = new AudioRecord(MediaRecorder.AudioSource.MIC,
RECORDER_SAMPLERATE, RECORDER_CHANNELS,
RECORDER_AUDIO_ENCODING, BufferElements2Rec * BytesPerElement);
recorder.startRecording();
isRecording = true;
recordingThread = new Thread(new Runnable() {
public void run() {
writeAudioDataToFile();
}
}, "AudioRecorder Thread");
recordingThread.start();
}
private byte[] short2byte(short[] sData) {
int shortArrsize = sData.length;
byte[] bytes = new byte[shortArrsize * 2];
for (int i = 0; i < shortArrsize; i++) {
bytes[i * 2] = (byte) (sData[i] & 0x00FF);
bytes[(i * 2) + 1] = (byte) (sData[i] >> 8);
sData[i] = 0;
}
return bytes;
}
private void writeAudioDataToFile() {
// Write the output audio in byte
String filePath = Environment.getExternalStorageDirectory().getAbsolutePath()+"/myrec.pcm";
short sData[] = new short[BufferElements2Rec];
FileOutputStream os = null;
try {
os = new FileOutputStream(filePath);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
while (isRecording) {
// gets the voice output from microphone to byte format
recorder.read(sData, 0, BufferElements2Rec);
System.out.println("Short wirting to file" + sData.toString());
try {
// // writes the data to file from buffer
// // stores the voice buffer
byte bData[] = short2byte(sData);
os.write(bData, 0, BufferElements2Rec * BytesPerElement);
} catch (IOException e) {
e.printStackTrace();
}
}
try {
os.close();
} catch (IOException e) {
e.printStackTrace();
}
}
public void Record_Stop()
{
if (null != recorder) {
isRecording = false;
recorder.stop();
recorder.release();
recorder = null;
recordingThread = null;
}
}
private View.OnClickListener btnClick = new View.OnClickListener() {
public void onClick(View v) {
switch (v.getId()) {
case R.id.Start: {
enableButtons(true);
Record();
break;
}
case R.id.Stop: {
enableButtons(false);
Record_Stop();
break;
}
}
}
};
#Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_BACK) {
finish();
}
return super.onKeyDown(keyCode, event);
}
}
As soon as I press the start button the app gets unexpectedly stopped.
com.example.kaushal.learningfft E/AndroidRuntime: FATAL EXCEPTION:
main Process: com.example.kaushal.learningfft, PID: 4705
java.lang.IllegalStateException: startRecording() called on an
uninitialized AudioRecord. at
android.media.AudioRecord.startRecording(AudioRecord.java:97‌​6) at
com.example.kaushal.learningfft.MainActivity.Record(MainActi‌​vity.java:57)
at
com.example.kaushal.learningfft.MainActivity$2.onClick(MainA‌​ctivity.java:126)
at android.view.View.performClick(View.java:5610) at
android.view.View$PerformClick.run(View.java:22265) at
android.os.Handler.handleCallback(Handler.java:751) at
android.os.Handler.dispatchMessage(Handler.java:95) at
android.os.Looper.loop(Looper.java:154)
android.app.ActivityThread.main(ActivityThread.java:6077) at
java.lang.reflect.Method.invoke(Native Method) at
com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(Z‌​ygoteInit.java:865)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:755)

How to save recorded sound to file by using AudioRecord in android?

I'm developing an android (compileSdkVersion 23) app to record audio by using AudioRecord and the reason of using it is to get frequency after FFT in real time.
Not only this work, I need to save the recorded sound to check the sound(In this process, tracking the frequency is unnecessary.)
How to save recorded sound to file by using the AudioRecord in android?
Thus, am I using the AudioRecord correctly?
Here is code:
public class MainActivity extends Activity {
int frequency = 8000;
int channelConfiguration = AudioFormat.CHANNEL_CONFIGURATION_MONO;
int audioEncoding = AudioFormat.ENCODING_PCM_16BIT;
AudioRecord audioRecord;
RecordAudio recordTask;
int blockSize;// = 256;
boolean started = false;
boolean CANCELLED_FLAG = false;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
blockSize = 256;
final Button btRec = (Button) findViewById(R.id.btRec);
btRec.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (started == true) {
//started = false;
CANCELLED_FLAG = true;
//recordTask.cancel(true);
try{
audioRecord.stop();
}
catch(IllegalStateException e){
Log.e("Stop failed", e.toString());
}
btRec.setText("Start");
// canvasDisplaySpectrum.drawColor(Color.BLACK);
}
else {
started = true;
CANCELLED_FLAG = false;
btRec.setText("Stop");
recordTask = new RecordAudio();
recordTask.execute();
}
}
});
}
private class RecordAudio extends AsyncTask<Void, double[], Boolean> {
#Override
protected Boolean doInBackground(Void... params) {
int bufferSize = AudioRecord.getMinBufferSize(frequency,
channelConfiguration, audioEncoding);
audioRecord = new AudioRecord(
MediaRecorder.AudioSource.DEFAULT, frequency,
channelConfiguration, audioEncoding, bufferSize);
int bufferReadResult;
short[] buffer = new short[blockSize];
double[] toTransform = new double[blockSize];
try {
audioRecord.startRecording();
} catch (IllegalStateException e) {
Log.e("Recording failed", e.toString());
}
while (started) {
if (isCancelled() || (CANCELLED_FLAG == true)) {
started = false;
//publishProgress(cancelledResult);
Log.d("doInBackground", "Cancelling the RecordTask");
break;
} else {
bufferReadResult = audioRecord.read(buffer, 0, blockSize);
for (int i = 0; i < blockSize && i < bufferReadResult; i++) {
toTransform[i] = (double) buffer[i] / 32768.0; // signed 16 bit
}
//transformer.ft(toTransform);
//publishProgress(toTransform);
}
}
return true;
}
}
}

You have to download your file and save in cache, than for any request you have to check for cahce file if it is available use otherwise request new file
For complete help look into one of my answer Download and cache media files

AudioRecorder not recording right

I am trying to use AudioRecorder to record a wav file for a certain interval of time (corresponding to a certain number of samples). to stop the recording i used Timer().schedule(delay) to stop after a while. but no matter what is the value of that delay the file is always the same size, and not readble.
public class Record extends Activity {
private static final int RECORDER_SAMPLERATE = 44100;
int compt=0;
int duration=1;
//int numSample= duration*RECORDER_SAMPLERATE;
private static final int RECORDER_CHANNELS = AudioFormat.CHANNEL_IN_MONO;
private static final int RECORDER_AUDIO_ENCODING = AudioFormat.ENCODING_PCM_16BIT;
private AudioRecord recorder = null;
private volatile Thread recordingThread=null;
private volatile boolean isRecording = false;
int bufferSize = AudioRecord.getMinBufferSize(RECORDER_SAMPLERATE,RECORDER_CHANNELS, RECORDER_AUDIO_ENCODING);
long mySubChunk1Size = 16;
short myBitsPerSample= 16;
int myFormat = 1;
int myChannels = 1;
long myByteRate =RECORDER_SAMPLERATE* myChannels * myBitsPerSample/8;
int myBlockAlign = myChannels * myBitsPerSample/8;
Handler handler;
String filePath = Environment.getExternalStorageDirectory().getAbsolutePath()+"/recordedSound"+compt+".wav";
DataOutputStream dd;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_raw_rec);
try
{
try {
startRec();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
new Timer().schedule(new TimerTask()
{
#Override
public void run()
{
recordingThread.interrupt();
recordingThread=null;
isRecording=false;
recorder.stop();
recorder.release();
recorder = null;
}
}
,5000); //execute after 5 seconds of recording
}//end try
catch(IllegalStateException e) {
e.printStackTrace();
}
}
private void startRec() throws IOException{
recorder = new AudioRecord(MediaRecorder.AudioSource.MIC,RECORDER_SAMPLERATE, RECORDER_CHANNELS,RECORDER_AUDIO_ENCODING, bufferSize);
recorder.startRecording();
isRecording = true;
recordingThread = new Thread(new Runnable() {
public void run() {
writeToFile();
}
}, "AudioRecorder Thread");
recordingThread.start();
}
private void writeToFile() {
// Write the output audio in byte
byte[] data= new byte[bufferSize];
while (isRecording) {
try{
recorder.read(data, 0, bufferSize);
Log.d("recorder value", "value"+recorder);
}
catch (NullPointerException e)
{
e.printStackTrace();
}
try {
// // writes the data to file from buffer
// // stores the voice buffer
dd=new DataOutputStream( new FileOutputStream(filePath));
dd.writeBytes("RIFF");
dd.writeInt(0); // Final file size not known yet, write 0
dd.writeBytes("WAVE");
dd.writeBytes("fmt ");
dd.writeInt(Integer.reverseBytes(16)); // Sub-chunk size, 16 for PCM
dd.writeShort(Short.reverseBytes((short) 1)); // AudioFormat, 1 for PCM
dd.writeShort(Short.reverseBytes( (short) myChannels));// Number of channels, 1 for mono, 2 for stereo
dd.writeInt(Integer.reverseBytes(RECORDER_SAMPLERATE)); // Sample rate
dd.writeInt(Integer.reverseBytes( (RECORDER_SAMPLERATE*myBitsPerSample*myChannels/8))); // Byte rate, SampleRate*NumberOfChannels*BitsPerSample/8
dd.writeShort(Short.reverseBytes((short) (myChannels*myBitsPerSample/8))); // Block align, NumberOfChannels*BitsPerSample/8
dd.writeShort(Short.reverseBytes( myBitsPerSample)); // Bits per sample
dd.writeBytes("data");
dd.write(data);
//dd.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
what am i doing wrong?

You're creating a new WAV file during every iteration of the while loop in writeToFile.
A better approach would be to write just the PCM data buffers (without any header) to a temporary file. And make sure you only create the FileOutputStream once.Then, when the recording has ended, generate the RIFF header and write it to the destination WAV file followed by the contents of your temporary file.

How to record audio using AudioRecorder in Android

I want to capture audio from an Android device. My code below seems to successfully make a wav file on the SD card but it cannot be played. I tried to play it using different media players but none work. There is an issue in my code that is causing this problem.
code
public class MainActivity extends ActionBarActivity {
private static final String LOG_TAG = "AudioRecordTest";
static final int AUDIO_PORT = 2048;
static final int SAMPLE_RATE = 8000;
static final int SAMPLE_INTERVAL = 20; // milliseconds
static final int SAMPLE_SIZE = 2; // bytes per sample
static final int BUF_SIZE = SAMPLE_INTERVAL * SAMPLE_INTERVAL * SAMPLE_SIZE * 2;
private static int[] mSampleRates = new int[]{44100, 44056, 47250, 48000, 22050, 16000, 11025, 8000};
private Thread recordingThread = null;
private boolean isRecording = false;
int BufferElements2Rec = 1024; // want to play 2048 (2K) since 2 bytes we
// use only 1024
int BytesPerElement = 2; // 2 bytes in 16bit format
private int bufferSize;
private AudioRecord recorder;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
startRecording();
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
private void startRecording() {
recorder = findAudioRecord();
recorder.startRecording();
isRecording = true;
recordingThread = new Thread(new Runnable() {
public void run() {
writeAudioDataToFile();
}
}, "AudioRecorder Thread");
recordingThread.start();
}
// convert short to byte
private byte[] short2byte(short[] sData) {
int shortArrsize = sData.length;
byte[] bytes = new byte[shortArrsize * 2];
for (int i = 0; i < shortArrsize; i++) {
bytes[i * 2] = (byte) (sData[i] & 0x00FF);
bytes[(i * 2) + 1] = (byte) (sData[i] >> 8);
sData[i] = 0;
}
return bytes;
}
public AudioRecord findAudioRecord() {
for (int rate : mSampleRates) {
for (short audioFormat : new short[]{AudioFormat.ENCODING_PCM_8BIT, AudioFormat.ENCODING_PCM_16BIT}) {
for (short channelConfig : new short[]{AudioFormat.CHANNEL_IN_MONO, AudioFormat.CHANNEL_IN_STEREO}) {
try {
Log.d(LOG_TAG, "Attempting rate " + rate + "Hz, bits: " + audioFormat + ", channel: "
+ channelConfig);
bufferSize = AudioRecord.getMinBufferSize(rate, channelConfig, audioFormat);
if (bufferSize != AudioRecord.ERROR_BAD_VALUE) {
// check if we can instantiate and have a success
recorder = new AudioRecord(MediaRecorder.AudioSource.DEFAULT, rate, channelConfig, audioFormat, bufferSize);
if (recorder.getState() == AudioRecord.STATE_INITIALIZED)
return recorder;
}
} catch (Exception e) {
Log.e(LOG_TAG, rate + "Exception, keep trying.", e);
}
}
}
}
return null;
}
private void writeAudioDataToFile() {
/*// Write the output audio in byte
short sData[] = new short[BufferElements2Rec];
while (isRecording) {
// gets the voice output from microphone to byte format
recorder.read(sData, 0, BufferElements2Rec);
System.out.println("Short wirting to file" + sData.toString());
// // stores the voice buffer
byte bData[] = short2byte(sData);
sendLiveAudio(bData);
}*/
String filePath = "/sdcard/test.wav";
short sData[] = new short[bufferSize / 2];
FileOutputStream os = null;
try {
os = new FileOutputStream(filePath);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
while (isRecording) {
// gets the voice output from microphone to byte format
recorder.read(sData, 0, bufferSize / 2);
Log.d("eray", "Short wirting to file" + sData.toString());
try {
// // writes the data to file from buffer
// // stores the voice buffer
byte bData[] = short2byte(sData);
os.write(bData, 0, bufferSize);
} catch (IOException e) {
e.printStackTrace();
}
}
try {
os.close();
} catch (IOException e) {
e.printStackTrace();
}
}
private void stopRecording() {
// stops the recording activity
if (null != recorder) {
isRecording = false;
recorder.stop();
recorder.release();
recorder = null;
recordingThread = null;
}
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
#Override
public void onBackPressed() {
super.onBackPressed();
stopRecording();
}
}

Try This.....
public class Audio_Record extends Activity {
private static final int RECORDER_SAMPLERATE = 8000;
private static final int RECORDER_CHANNELS = AudioFormat.CHANNEL_IN_MONO;
private static final int RECORDER_AUDIO_ENCODING = AudioFormat.ENCODING_PCM_16BIT;
private AudioRecord recorder = null;
private Thread recordingThread = null;
private boolean isRecording = false;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
setButtonHandlers();
enableButtons(false);
int bufferSize = AudioRecord.getMinBufferSize(RECORDER_SAMPLERATE,
RECORDER_CHANNELS, RECORDER_AUDIO_ENCODING);
}
private void setButtonHandlers() {
((Button) findViewById(R.id.btnStart)).setOnClickListener(btnClick);
((Button) findViewById(R.id.btnStop)).setOnClickListener(btnClick);
}
private void enableButton(int id, boolean isEnable) {
((Button) findViewById(id)).setEnabled(isEnable);
}
private void enableButtons(boolean isRecording) {
enableButton(R.id.btnStart, !isRecording);
enableButton(R.id.btnStop, isRecording);
}
int BufferElements2Rec = 1024; // want to play 2048 (2K) since 2 bytes we use only 1024
int BytesPerElement = 2; // 2 bytes in 16bit format
private void startRecording() {
recorder = new AudioRecord(MediaRecorder.AudioSource.MIC,
RECORDER_SAMPLERATE, RECORDER_CHANNELS,
RECORDER_AUDIO_ENCODING, BufferElements2Rec * BytesPerElement);
recorder.startRecording();
isRecording = true;
recordingThread = new Thread(new Runnable() {
public void run() {
writeAudioDataToFile();
}
}, "AudioRecorder Thread");
recordingThread.start();
}
//convert short to byte
private byte[] short2byte(short[] sData) {
int shortArrsize = sData.length;
byte[] bytes = new byte[shortArrsize * 2];
for (int i = 0; i < shortArrsize; i++) {
bytes[i * 2] = (byte) (sData[i] & 0x00FF);
bytes[(i * 2) + 1] = (byte) (sData[i] >> 8);
sData[i] = 0;
}
return bytes;
}
private void writeAudioDataToFile() {
// Write the output audio in byte
String filePath = "/sdcard/voice8K16bitmono.pcm";
short sData[] = new short[BufferElements2Rec];
FileOutputStream os = null;
try {
os = new FileOutputStream(filePath);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
while (isRecording) {
// gets the voice output from microphone to byte format
recorder.read(sData, 0, BufferElements2Rec);
System.out.println("Short wirting to file" + sData.toString());
try {
// // writes the data to file from buffer
// // stores the voice buffer
byte bData[] = short2byte(sData);
os.write(bData, 0, BufferElements2Rec * BytesPerElement);
} catch (IOException e) {
e.printStackTrace();
}
}
try {
os.close();
} catch (IOException e) {
e.printStackTrace();
}
}
private void stopRecording() {
// stops the recording activity
if (null != recorder) {
isRecording = false;
recorder.stop();
recorder.release();
recorder = null;
recordingThread = null;
}
}
private View.OnClickListener btnClick = new View.OnClickListener() {
public void onClick(View v) {
switch (v.getId()) {
case R.id.btnStart: {
enableButtons(true);
startRecording();
break;
}
case R.id.btnStop: {
enableButtons(false);
stopRecording();
break;
}
}
}
};
#Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_BACK) {
finish();
}
return super.onKeyDown(keyCode, event);
}
}

Reading data from a microphone in android to process it online

I have a problem reading audiodata from microphone in android. My app must change lightness of a logo picture depending on volume of a sound, which I read from microphone. I use AudioRecord class to get audiodata. Depending on sample rate and buffer size, every 2nd/4th/8th read operation goes with latency of 100-200 ms. So my app can't react on volume changes properly. I tried to reduce buffer size, and to execute data processing in other thread (using AudioRecord.setPositionNotificationPeriod() and callback) but those not make much sense - latency just becomes a little shorter. Here is my code:
package com.mikesoft.Clown;
import android.app.Activity;
import android.media.AudioFormat;
import android.media.AudioRecord.OnRecordPositionUpdateListener;
import android.media.AudioRecord;
import android.media.MediaRecorder.AudioSource;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import java.lang.Math;
public class TestActivity extends Activity implements OnClickListener, OnRecordPositionUpdateListener {
private static final String LOG_TAG = TestActivity.class.getSimpleName();
//arrays for selecting usable audioformat
private static int[] mSampleRates = new int[] {8000, 11025, 22050, 44100};
private static short[] audioFormat = new short[] {AudioFormat.ENCODING_PCM_8BIT, AudioFormat.ENCODING_PCM_16BIT};
private static short[] channelConfig = new short[] {AudioFormat.CHANNEL_CONFIGURATION_MONO, AudioFormat.CHANNEL_CONFIGURATION_STEREO};
private short[][] buffers;
private int ix;
private AudioRecord recorder = null;
private int bufferSize = 0;
private AudioThread recordingThread = null;
private boolean isRecording = false;
/** The OpenGL View */
private LogoView glSurface;
//markers
private short[] buffer;
private long read_time;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.layout_test);
findViewById(R.id.btnStart).setOnClickListener(this);
findViewById(R.id.btnStop).setOnClickListener(this);
mVolumeText = (TextView)findViewById(R.id.volume);
setRecordMode();
glSurface = (LogoView)findViewById(R.id.glSurface);
}
private void setRecordMode() {
((Button) findViewById(R.id.btnStop)).setClickable(isRecording);
((Button) findViewById(R.id.btnStart)).setClickable(!isRecording);
}
public void startRecording() {
if (null == recorder) {
recorder = findAudioRecord();
recorder.setRecordPositionUpdateListener(this);
recorder.startRecording();
isRecording = true;
recordingThread = new AudioThread();
}
Log.d(LOG_TAG, "Audio recording started");
}
//thread for executing audio recorder
private class AudioThread extends Thread {
private AudioThread() {
start();
}
#Override
public void run() {
android.os.Process.setThreadPriority(android.os.Process.THREAD_PRIORITY_URGENT_AUDIO);
recordAudio();
}
}
private void recordAudio() {
ix = 0;
int read = 0;
recorder.setPositionNotificationPeriod(bufferSize);
while (isRecording) {
//long t1 = System.currentTimeMillis();
buffer = buffers[ix++ % buffers.length];
read = recorder.read(buffer, 0, buffer.length);
//time after reading
//read_time = System.currentTimeMillis();
//Log.d(LOG_TAG, "read bytes: " + read);
//Log.d(LOG_TAG, "read_time=" + (read_time - t1));
//int vol = 0;
//for (int i=0;i<buffer.length;i++)
// vol = Math.max(vol, Math.abs(buffer[i]));
//float norm = (float)vol/(float)Short.MAX_VALUE;
//glSurface.setLightness(norm);
}
}
//initialize AudioRecord with suitable format
public AudioRecord findAudioRecord() {
//for (int rate : mSampleRates) {
int rate = 22050;
for (short format : audioFormat) {
for (short channel : channelConfig) {
try {
Log.d(LOG_TAG, "Attempting rate " + rate + "Hz, bits: " + audioFormat + ", channel: "
+ channelConfig);
bufferSize = AudioRecord.getMinBufferSize(rate, channel, format);
if (bufferSize != AudioRecord.ERROR_BAD_VALUE) {
// check if we can instantiate and have a success
AudioRecord recorder = new AudioRecord(AudioSource.MIC, rate, channel, format, bufferSize);
//bufferSize/=8;
if (recorder.getState() == AudioRecord.STATE_INITIALIZED) {
buffers = new short[256][bufferSize];
return recorder;
}
}
} catch (Exception e) {
Log.e(LOG_TAG, rate + "Exception, keep trying.",e);
}
}
}
//}
return null;
}
public void stopRecording() {
if (null != recorder) {
isRecording = false;
recorder.stop();
recorder.release();
recorder = null;
recordingThread = null;
}
Log.d(LOG_TAG, "Audio recording stopped");
}
#Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.btnStart:
startRecording();
setRecordMode();
break;
case R.id.btnStop:
stopRecording();
setRecordMode();
break;
default:
break;
}
}
#Override
public void onMarkerReached(AudioRecord arg0) {
// TODO Auto-generated method stub
}
#Override
public void onPeriodicNotification(AudioRecord arg0) {
float norm;
short[] buf = buffers[ix % buffers.length];
int vol = 0;
for (int i = 0; i < buf.length; i++)
vol = Math.max(vol, Math.abs(buf[i]));
norm = (float) vol / (float) Short.MAX_VALUE;
glSurface.setLightness(norm);
}
}
I tried devices&emulators with Android 1.6-3.2 but it's the same thing everywhere. Is there a solution for my problem in Java? Or I should use NDK approaches?
Will appreciate any help.