文章目录
AudioTrack，MediaPlayer，SoundPool的区别
- mediaplayer适合长时间播放音乐
- soundpool适合短时间的音频片段，如游戏声音，按键声音
- audiotrack更接近底层，更灵活，播放的是pcm音频数据
AudioTrack的使用
public AudioTrack(int streamType, int sampleRateInHz, int channelConfig, int audioFormat,
int bufferSizeInBytes, int mode)
- streamType
音频管理策略，如我们在小米手机调节音量时，会出现3种声音调节的类型，音乐，铃声，闹钟 该参数的可选值在AudioManager类中，如：
STREAM_MUSCI：音乐声 STREAM_RING：铃声 STREAM_NOTIFICATION：通知声
- sampleRateInHz
采样率，看源码知道，范围在4000~192000
public static final int SAMPLE_RATE_HZ_MIN = 4000; public static final int SAMPLE_RATE_HZ_MAX = 192000;
- channelConfig
通道数的配置，可选值在AudioFormat中以常量值定义，常用的如下
public static final int CHANNEL_IN_LEFT = 0x4; public static final int CHANNEL_IN_RIGHT = 0x8; public static final int CHANNEL_IN_FRONT = 0x10; //单通道 public static final int CHANNEL_IN_MONO = CHANNEL_IN_FRONT; //双通道 public static final int CHANNEL_IN_STEREO = (CHANNEL_IN_LEFT | CHANNEL_IN_RIGHT);
- audioFormat
用来配置数据位宽，可选值在可选值在AudioFormat中以常量值定义，常用的如下
public static final int ENCODING_PCM_16BIT = 2; public static final int ENCODING_PCM_8BIT = 3;
- bufferSizeInBytes
配置的是AudioTrack内部音频缓冲区的大小，同样AudioTrack提供了获取缓冲区大小的方法
AudioTrack.getMinBufferSize(sampleRateInHz, channelConfig, audioFormat);
- mode
AudioTrack有两种播放方式 MODE_STATIC和MODE_STREAM前者是一次性将所有数据写入播放缓冲区，然后播放 后者是一边写入一边播放
音频播放方法
mAudioTrack.play(); //开始播放 mAudioTrack.stop(); //停止播放 mAudioTrack.write(audioData,offsetInBytes,sizeInBytes);//将pcm数据写入缓冲区
示例代码
public class AudioPlayer {
private static final String TAG = "AudioPlayer";
private final int DEFAULT_STREAM_TYPE = AudioManager.STREAM_MUSIC; //流音乐
private final int DEFAULT_RATE = 44100; //采样率
private final int DEFAULT_CHANNEL = AudioFormat.CHANNEL_IN_STEREO; //双通道(左右声道)
private final int DEFAULT_FORMAT = AudioFormat.ENCODING_PCM_16BIT; //数据位宽16位
private static final int DEFAULT_PLAY_MODE = AudioTrack.MODE_STREAM;
private AudioTrack mAudioTrack;
private int mMinBufferSize;
private boolean isPlaying=false;
public void startPlay(){
startPlay(DEFAULT_STREAM_TYPE,DEFAULT_RATE,DEFAULT_CHANNEL,DEFAULT_FORMAT);
}
public void startPlay(int streamType, int sampleRateInHz, int channelConfig, int audioFormat){
if(isPlaying){
Log.d(TAG,"AudioPlayer has played");
return;
}
mMinBufferSize = AudioTrack.getMinBufferSize(sampleRateInHz, channelConfig, audioFormat);
if (mMinBufferSize == AudioRecord.ERROR_BAD_VALUE) {
Log.d(TAG, "Invalid parameter");
return;
}
mAudioTrack=new AudioTrack(streamType,sampleRateInHz,channelConfig,audioFormat,
mMinBufferSize,DEFAULT_PLAY_MODE);
if(mAudioTrack.getState()==AudioTrack.STATE_UNINITIALIZED){
Log.d(TAG, "AudioTrack initialize fail");
return;
}
isPlaying=true;
}
public void stopPlay(){
if(!isPlaying){
Log.d(TAG, "AudioTrack is not playing");
return;
}
if(mAudioTrack.getPlayState()==AudioTrack.PLAYSTATE_PLAYING){
mAudioTrack.stop();
}
mAudioTrack.release();
isPlaying=false;
}
private void play(byte[] audioData,int offsetInBytes, int sizeInBytes){
if(!isPlaying){
Log.d(TAG, "AudioTrack not start");
return;
}
if(sizeInBytes<mMinBufferSize){
Log.d(TAG, "audio data not enough");
//return;
}
if(mAudioTrack.write(audioData,offsetInBytes,sizeInBytes)!=mMinBufferSize){
Log.d(TAG, "AudioTrack can not write all the data");
}
mAudioTrack.play();
Log.d(TAG, "played "+sizeInBytes+" bytes");
}
}
测试
//原始音频的录入和播放
public class AudioPCMActivity extends DemoActivity {
private Button btn_audio_record;
private Button btn_audio_record_play;
private AudioCapture audioCapture;
private AudioPlayer audioPlayer;
private PcmFileWriter pcmFileWriter;
private PcmFileReader pcmFileReader;
private boolean isReading;
private String path="";
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
setContentView(R.layout.activity_media_audio);
super.onCreate(savedInstanceState);
}
@Override
public void initHead() {
}
@Override
public void initView() {
btn_audio_record=findViewById(R.id.btn_audio_record);
btn_audio_record_play=findViewById(R.id.btn_audio_record_play);
}
@Override
public void initData() {
path=FileUtil.getAudioDir(this)+"/audioTest.pcm";
audioCapture=new AudioCapture();
audioPlayer=new AudioPlayer();
pcmFileReader=new PcmFileReader();
pcmFileWriter=new PcmFileWriter();
String des = "录音权限被禁止，我们需要打开录音权限";
String[] permissions = new String[]{Manifest.permission.RECORD_AUDIO};
baseAt.requestPermissions(des, permissions, 100, new PermissionsResultListener() {
@Override
public void onPermissionGranted() {
}
@Override
public void onPermissionDenied() {
finish();
}
});
}
@Override
public void initEvent() {
btn_audio_record.setOnTouchListener(new View.OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
if(event.getAction()==MotionEvent.ACTION_DOWN){
Log.d("TAG","按住");
start();
}else if(event.getAction()==MotionEvent.ACTION_UP){
Log.d("TAG","松开");
stop();
}
return false;
}
});
btn_audio_record_play.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
play();
}
});
}
//播放录音
private void play(){
isReading=true;
pcmFileReader.openFile(path);
audioPlayer.startPlay();
new AudioTrackThread().start();
}
private class AudioTrackThread extends Thread{
@Override
public void run() {
byte[] buffer = new byte[1024];
while (isReading && pcmFileReader.read(buffer,0,buffer.length)>0){
audioPlayer.play(buffer,0,buffer.length);
}
audioPlayer.stopPlay();
pcmFileReader.closeFile();
}
}
//开始录音
private void start(){
pcmFileWriter.openFile(path);
btn_audio_record.setText("松开 结束");
audioCapture.startRecord();
audioCapture.setOnAudioFrameCaptureListener(new AudioCapture.onAudioFrameCaptureListener() {
@Override
public void onAudioFrameCapture(byte[] audioData) {
pcmFileWriter.write(audioData,0,audioData.length);
}
});
}
//结束录音
private void stop(){
btn_audio_record.setText("按住 录音");
audioCapture.stopRecord();
pcmFileWriter.closeFile();
}
}
