本文來自http://blog.csdn.net/hellogv/
，引用必須註明出處！
Android可以通過MediaRecorder和AudioRecord這兩個工具來實現錄音，MediaRecorder直接把麥克風的數據存到文件，並且能夠直接進行編碼(如AMR,MP3等)，而AudioRecord則是讀取麥克風的音頻流。本文使用AudioRecord讀取音頻流，使用AudioTrack播放音頻流，通過“邊讀邊播放”以及增大音量的方式來實現一個簡單的助聽器程序。
PS：由於目前的Android模擬器還不支持AudioRecord，因此本程序需要編譯之後放到真機運行。
先貼出本文程序運行截圖：
PS：程序音量調節只是程序內部調節音量而已，要調到最大音量還需要手動設置系統音量。
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使用AudioRecord必須要申請許可，在AndroidManifest.xml裏面添加這句：
- <uses-permission android:name=\"android.permission.RECORD_AUDIO\"></uses-permission>
<uses-permission android:name=\"android.permission.RECORD_AUDIO\"></uses-permission>
main.xml的源碼如下：
- <?xml version=\"1.0\" encoding=\"utf-8\"?>
- <LinearLayout xmlns:android=\"http://schemas.android.com/apk/res/android\"
android:orientation=\"vertical\" android:layout_width=\"fill_parent\"
android:layout_height=\"fill_parent\">
<Button android:layout_height=\"wrap_content\" android:id=\"@+id/btnRecord\"
android:layout_width=\"fill_parent\" android:text=\"開始邊錄邊放\"></Button>
<Button android:layout_height=\"wrap_content\"
android:layout_width=\"fill_parent\" android:text=\"停止\" android:id=\"@+id/btnStop\"></Button>
<Button android:layout_height=\"wrap_content\" android:id=\"@+id/btnExit\"
android:layout_width=\"fill_parent\" android:text=\"退出\"></Button>
<TextView android:id=\"@+id/TextView01\" android:layout_height=\"wrap_content\"
android:text=\"程序音量調節\" android:layout_width=\"fill_parent\"></TextView>
<SeekBar android:layout_height=\"wrap_content\" android:id=\"@+id/skbVolume\"
android:layout_width=\"fill_parent\"></SeekBar>
</LinearLayout> <?xml version=\"1.0\" encoding=\"utf-8\"?> <LinearLayout xmlns:android=\"http://schemas.android.com/apk/res/android\" android:orientation=\"vertical\"
android:layout_width=\"fill_parent\" android:layout_height=\"fill_parent\"> <Button android:layout_height=\"wrap_content\" android:id=\"@+id/btnRecord\" android:layout_width=\"fill_parent\" android:text=\"開始邊錄邊放\"></Button> <Button android:layout_height=\"wrap_content\"
android:layout_width=\"fill_parent\" android:text=\"停止\" android:id=\"@+id/btnStop\"></Button> <Button android:layout_height=\"wrap_content\" android:id=\"@+id/btnExit\" android:layout_width=\"fill_parent\" android:text=\"退出\"></Button> <TextView android:id=\"@+id/TextView01\"
android:layout_height=\"wrap_content\" android:text=\"程序音量調節\" android:layout_width=\"fill_parent\"></TextView> <SeekBar android:layout_height=\"wrap_content\" android:id=\"@+id/skbVolume\" android:layout_width=\"fill_parent\"></SeekBar> </LinearLayout>
testRecord.java的源碼如下：
- package com.testRecord;
-
- import android.app.Activity;
import android.media.AudioFormat;
import android.media.AudioManager;
import android.media.AudioRecord;
import android.media.AudioTrack;
import android.media.MediaRecorder;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.SeekBar;
import android.widget.Toast;
public class testRecord extends Activity {
/** Called when the activity is first created. */
Button btnRecord, btnStop, btnExit; SeekBar skbVolume;//調節音量
boolean isRecording = false;//是否錄放的標記
static final int frequency = 44100;
static final int channelConfiguration = AudioFormat.CHANNEL_CONFIGURATION_MONO;
static final int audioEncoding = AudioFormat.ENCODING_PCM_16BIT;
int recBufSize,playBufSize;
AudioRecord audioRecord; AudioTrack audioTrack; @Override public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main); setTitle(\"助聽器\");
recBufSize = AudioRecord.getMinBufferSize(frequency, channelConfiguration, audioEncoding); playBufSize=AudioTrack.getMinBufferSize(frequency, channelConfiguration, audioEncoding); // -----------------------------------------
audioRecord = new AudioRecord(MediaRecorder.AudioSource.MIC, frequency,
channelConfiguration, audioEncoding, recBufSize);
audioTrack = new AudioTrack(AudioManager.STREAM_MUSIC, frequency,
channelConfiguration, audioEncoding, playBufSize, AudioTrack.MODE_STREAM); //------------------------------------------
btnRecord = (Button) this.findViewById(R.id.btnRecord);
btnRecord.setOnClickListener(new ClickEvent());
btnStop = (Button) this.findViewById(R.id.btnStop);
btnStop.setOnClickListener(new ClickEvent());
btnExit = (Button) this.findViewById(R.id.btnExit);
btnExit.setOnClickListener(new ClickEvent());
skbVolume=(SeekBar)this.findViewById(R.id.skbVolume);
skbVolume.setMax(100);//音量調節的極限
skbVolume.setProgress(70);//設置seekbar的位置值
audioTrack.setStereoVolume(0.7f, 0.7f);//設置當前音量大小
skbVolume.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
float vol=(float)(seekBar.getProgress())/(float)(seekBar.getMax());
audioTrack.setStereoVolume(vol, vol);//設置音量
} @Override
public void onStartTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
} @Override
public void onProgressChanged(SeekBar seekBar, int progress,
boolean fromUser) {
// TODO Auto-generated method stub
} }); } @Override protected void onDestroy() {
super.onDestroy();
android.os.Process.killProcess(android.os.Process.myPid());
} class ClickEvent implements View.OnClickListener {
@Override
public void onClick(View v) {
if (v == btnRecord) {
isRecording = true;
new RecordPlayThread().start();// 開一條線程邊錄邊放
} else if (v == btnStop) {
isRecording = false;
} else if (v == btnExit) {
isRecording = false;
testRecord.this.finish();
} } } class RecordPlayThread extends Thread {
public void run() {
try {
byte[] buffer = new byte[recBufSize];
audioRecord.startRecording();//開始錄製
audioTrack.play();//開始播放
while (isRecording) {
//從MIC保存數據到緩衝區
int bufferReadResult = audioRecord.read(buffer, 0,
recBufSize); byte[] tmpBuf = new byte[bufferReadResult];
System.arraycopy(buffer, 0, tmpBuf, 0, bufferReadResult);
//寫入數據即播放
audioTrack.write(tmpBuf, 0, tmpBuf.length);
} audioTrack.stop(); audioRecord.stop(); } catch (Throwable t) {
Toast.makeText(testRecord.this, t.getMessage(), 1000);
} } }; }
