AudioRecord实现"助听器" ,录制和播放功能

转载自:http://blog.youkuaiyun.com/hellogv/

 

Android可以通过MediaRecorder和AudioRecord这两个工具来实现录音，MediaRecorder直接把麦克风的数据存到文件，并且能够直接进行编码(如AMR,MP3等)，而AudioRecord则是读取麦克风的音频流。本文使用AudioRecord读取音频流，使用AudioTrack播放音频流，通过“边读边播放”以及增大音量的方式来实现一个简单的助听器程序。

PS：由于目前的Android模拟器还不支持AudioRecord，因此本程序需要编译之后放到真机运行。

先贴出本文程序运行截图：

PS：程序音量调节只是程序内部调节音量而已，要调到最大音量还需要手动设置系统音量。

 

 

使用AudioRecord必须要申请许可，在AndroidManifest.xml里面添加这句：

 

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

main.xml的源码如下：

01.<?xml version="1.0" encoding="utf-8"?>  
02.<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"  
03.    android:orientation="vertical" android:layout_width="fill_parent"  
04.    android:layout_height="fill_parent">  
05.  
06.    <Button android:layout_height="wrap_content" android:id="@+id/btnRecord"  
07.        android:layout_width="fill_parent" android:text="开始边录边放"></Button>  
08.    <Button android:layout_height="wrap_content"  
09.        android:layout_width="fill_parent" android:text="停止" android:id="@+id/btnStop"></Button>  
10.    <Button android:layout_height="wrap_content" android:id="@+id/btnExit"  
11.        android:layout_width="fill_parent" android:text="退出"></Button>  
12.    <TextView android:id="@+id/TextView01" android:layout_height="wrap_content"  
13.        android:text="程序音量调节" android:layout_width="fill_parent"></TextView>  
14.    <SeekBar android:layout_height="wrap_content" android:id="@+id/skbVolume"  
15.        android:layout_width="fill_parent"></SeekBar>  
16.  
17.</LinearLayout>  

testRecord.java的源码如下：

01.package com.testRecord;  
02.  
03.import android.app.Activity;  
04.import android.media.AudioFormat;  
05.import android.media.AudioManager;  
06.import android.media.AudioRecord;  
07.import android.media.AudioTrack;  
08.import android.media.MediaRecorder;  
09.import android.os.Bundle;  
10.import android.view.View;  
11.import android.widget.Button;  
12.import android.widget.SeekBar;  
13.import android.widget.Toast;  
14.  
15.public class testRecord extends Activity {  
16.    /** Called when the activity is first created. */  
17.    Button btnRecord, btnStop, btnExit;  
18.    SeekBar skbVolume;//调节音量   
19.    boolean isRecording = false;//是否录放的标记   
20.    static final int frequency = 44100;  
21.    static final int channelConfiguration = AudioFormat.CHANNEL_CONFIGURATION_MONO;  
22.    static final int audioEncoding = AudioFormat.ENCODING_PCM_16BIT;  
23.    int recBufSize,playBufSize;  
24.    AudioRecord audioRecord;  
25.    AudioTrack audioTrack;  
26.  
27.    @Override  
28.    public void onCreate(Bundle savedInstanceState) {  
29.        super.onCreate(savedInstanceState);  
30.        setContentView(R.layout.main);  
31.        setTitle("助听器");  
32.        recBufSize = AudioRecord.getMinBufferSize(frequency,  
33.                channelConfiguration, audioEncoding);  
34.  
35.        playBufSize=AudioTrack.getMinBufferSize(frequency,  
36.                channelConfiguration, audioEncoding);  
37.        // -----------------------------------------   
38.        audioRecord = new AudioRecord(MediaRecorder.AudioSource.MIC, frequency,  
39.                channelConfiguration, audioEncoding, recBufSize);  
40.  
41.        audioTrack = new AudioTrack(AudioManager.STREAM_MUSIC, frequency,  
42.                channelConfiguration, audioEncoding,  
43.                playBufSize, AudioTrack.MODE_STREAM);  
44.        //------------------------------------------   
45.        btnRecord = (Button) this.findViewById(R.id.btnRecord);  
46.        btnRecord.setOnClickListener(new ClickEvent());  
47.        btnStop = (Button) this.findViewById(R.id.btnStop);  
48.        btnStop.setOnClickListener(new ClickEvent());  
49.        btnExit = (Button) this.findViewById(R.id.btnExit);  
50.        btnExit.setOnClickListener(new ClickEvent());  
51.        skbVolume=(SeekBar)this.findViewById(R.id.skbVolume);  
52.        skbVolume.setMax(100);//音量调节的极限   
53.        skbVolume.setProgress(70);//设置seekbar的位置值   
54.        audioTrack.setStereoVolume(0.7f, 0.7f);//设置当前音量大小   
55.        skbVolume.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {  
56.              
57.            @Override  
58.            public void onStopTrackingTouch(SeekBar seekBar) {  
59.                float vol=(float)(seekBar.getProgress())/(float)(seekBar.getMax());  
60.                audioTrack.setStereoVolume(vol, vol);//设置音量   
61.            }  
62.              
63.            @Override  
64.            public void onStartTrackingTouch(SeekBar seekBar) {  
65.                // TODO Auto-generated method stub   
66.            }  
67.              
68.            @Override  
69.            public void onProgressChanged(SeekBar seekBar, int progress,  
70.                    boolean fromUser) {  
71.                // TODO Auto-generated method stub   
72.            }  
73.        });  
74.    }  
75.  
76.    @Override  
77.    protected void onDestroy() {  
78.        super.onDestroy();  
79.        android.os.Process.killProcess(android.os.Process.myPid());  
80.    }  
81.  
82.    class ClickEvent implements View.OnClickListener {  
83.  
84.        @Override  
85.        public void onClick(View v) {  
86.            if (v == btnRecord) {  
87.                isRecording = true;  
88.                new RecordPlayThread().start();// 开一条线程边录边放   
89.            } else if (v == btnStop) {  
90.                isRecording = false;  
91.            } else if (v == btnExit) {  
92.                isRecording = false;  
93.                testRecord.this.finish();  
94.            }  
95.        }  
96.    }  
97.  
98.    class RecordPlayThread extends Thread {  
99.        public void run() {  
100.            try {  
101.                byte[] buffer = new byte[recBufSize];  
102.                audioRecord.startRecording();//开始录制   
103.                audioTrack.play();//开始播放   
104.                  
105.                while (isRecording) {  
106.                    //从MIC保存数据到缓冲区   
107.                    int bufferReadResult = audioRecord.read(buffer, 0,  
108.                            recBufSize);  
109.  
110.                    byte[] tmpBuf = new byte[bufferReadResult];  
111.                    System.arraycopy(buffer, 0, tmpBuf, 0, bufferReadResult);  
112.                    //写入数据即播放   
113.                    audioTrack.write(tmpBuf, 0, tmpBuf.length);  
114.                }  
115.                audioTrack.stop();  
116.                audioRecord.stop();  
117.            } catch (Throwable t) {  
118.                Toast.makeText(testRecord.this, t.getMessage(), 1000);  
119.            }  
120.        }  
121.    };  
122.}