Android MediaCodec解码aac,播放.

public class AudioDecoder {

private static final String TAG = "AudioDecoder";
public static final int KEY_CHANNEL_COUNT = 0;
private Worker mWorker;
private String path;//aac文件的路径。

public AudioDecoder(String filename) {
this.path = filename;
}

public void start() {
if (mWorker == null) {
mWorker = new Worker();
mWorker.setRunning(true);
mWorker.start();
}
}

public void stop() {
if (mWorker != null) {
mWorker.setRunning(false);
mWorker = null;
}

}

private class Worker extends Thread {
private static final int KEY_SAMPLE_RATE = 0;
private boolean isRunning = false;
private AudioTrack mPlayer;
private MediaCodec mDecoder;
private MediaExtractor extractor;

public void setRunning(boolean run) {
isRunning = run;
}

@Override
public void run() {
super.run();
if (!prepare()) {
isRunning = false;
Log.d(TAG, "音频解码器初始化失败");
}
while (isRunning) {
decode();
}
release();
}

/**
* 等待客户端连接，初始化解码器
*
* @return 初始化失败返回false，成功返回true
*/
public boolean prepare() {
// 等待客户端
mPlayer = new AudioTrack(AudioManager.STREAM_MUSIC, 8000, AudioFormat.CHANNEL_OUT_STEREO,
AudioFormat.ENCODING_PCM_16BIT, 2048, AudioTrack.MODE_STREAM);//
mPlayer.play();
try {
mDecoder = MediaCodec.createDecoderByType("audio/mp4a-latm");

final String encodeFile = path;
extractor = new MediaExtractor();
extractor.setDataSource(encodeFile);

MediaFormat mediaFormat = null;
for (int i = 0; i < extractor.getTrackCount(); i++) {
MediaFormat format = extractor.getTrackFormat(i);
String mime = format.getString(MediaFormat.KEY_MIME);
if (mime.startsWith("audio/")) {
extractor.selectTrack(i);
mediaFormat = format;
break;
}
}
mediaFormat.setString(MediaFormat.KEY_MIME, "audio/mp4a-latm");
mediaFormat.setInteger(MediaFormat.KEY_CHANNEL_COUNT, KEY_CHANNEL_COUNT);
mediaFormat.setInteger(MediaFormat.KEY_SAMPLE_RATE, KEY_SAMPLE_RATE);
mediaFormat.setInteger(MediaFormat.KEY_BIT_RATE, 24000);
mediaFormat.setInteger(MediaFormat.KEY_IS_ADTS, 1);
mediaFormat.setInteger(MediaFormat.KEY_AAC_PROFILE, 0);
mDecoder.configure(mediaFormat, null, null, 0);
} catch (IOException e) {
e.printStackTrace();
return false;
}
if (mDecoder == null) {
Log.e(TAG, "create mediaDecode failed");
return false;
}
mDecoder.start();
return true;
}

/**
* aac解码+播放
*/
public void decode() {
ByteBuffer[] codecInputBuffers = mDecoder.getInputBuffers();
ByteBuffer[] codecOutputBuffers = mDecoder.getOutputBuffers();

final long kTimeOutUs = 5000;
MediaCodec.BufferInfo info = new MediaCodec.BufferInfo();
boolean sawInputEOS = false;
boolean sawOutputEOS = false;
int totalRawSize = 0;
try {
while (!sawOutputEOS) {
if (!sawInputEOS) {
int inputBufIndex = mDecoder.dequeueInputBuffer(kTimeOutUs);
if (inputBufIndex >= 0) {
ByteBuffer dstBuf = codecInputBuffers[inputBufIndex];
int sampleSize = extractor.readSampleData(dstBuf, 0);
if (sampleSize < 0) {
Log.i("TAG", "saw input EOS.");
sawInputEOS = true;
mDecoder.queueInputBuffer(inputBufIndex, 0, 0, 0, MediaCodec.BUFFER_FLAG_END_OF_STREAM);
} else {
long presentationTimeUs = extractor.getSampleTime();
mDecoder.queueInputBuffer(inputBufIndex, 0, sampleSize, presentationTimeUs, 0);
extractor.advance();
}
}
}
int res = mDecoder.dequeueOutputBuffer(info, kTimeOutUs);
if (res >= 0) {

int outputBufIndex = res;
// Simply ignore codec config buffers.
if ((info.flags & MediaCodec.BUFFER_FLAG_CODEC_CONFIG) != 0) {
Log.i("TAG", "audio encoder: codec config buffer");
mDecoder.releaseOutputBuffer(outputBufIndex, false);
continue;
}

if (info.size != 0) {

ByteBuffer outBuf = codecOutputBuffers[outputBufIndex];

outBuf.position(info.offset);
outBuf.limit(info.offset + info.size);
byte[] data = new byte[info.size];
outBuf.get(data);
totalRawSize += data.length;
// fosDecoder.write(data);
// 播放音乐
mPlayer.write(data, 0, info.size);

}

mDecoder.releaseOutputBuffer(outputBufIndex, false);

if ((info.flags & MediaCodec.BUFFER_FLAG_END_OF_STREAM) != 0) {
Log.i("TAG", "saw output EOS.");
sawOutputEOS = true;
}

} else if (res == MediaCodec.INFO_OUTPUT_BUFFERS_CHANGED) {
codecOutputBuffers = mDecoder.getOutputBuffers();
Log.i("TAG", "output buffers have changed.");
} else if (res == MediaCodec.INFO_OUTPUT_FORMAT_CHANGED) {
MediaFormat oformat = mDecoder.getOutputFormat();
Log.i("TAG", "output format has changed to " + oformat);
}
}
} finally {
// fosDecoder.close();
extractor.release();
}
}

/**
* 释放资源
*/
private void release() {
if (mDecoder != null) {
mDecoder.stop();
mDecoder.release();

}
if (mPlayer != null) {
mPlayer.stop();
mPlayer.release();
mPlayer = null;
}
if (extractor != null) {
extractor.release();
extractor = null;
}
}
}
}

String fielPath = (Environment.getExternalStorageDirectory().getPath() + "/audio.aac");
AudioDecoder audioDecoder = new AudioDecoder(fielPath);
audioDecoder.start();