android 端音频采集与播放

AudioRecord(int audioSource, int sampleRateInHz, int channelConfig, int audioFormat, int bufferSizeInBytes)

 AudioRecord.getMinBufferSize(sampleRateInHz, channelConfig, audioFormat);

   if (mAudioRecord.getState() == AudioRecord.STATE_UNINITIALIZED) {            Log.e(TAG, "AudioRecord initialize fail !");            return false;        }

 mAudioRecord.startRecording();

    private class AudioCaptureRunnable implements Runnable {
        @Override        public void run() {            try {                while (!mIsLoopExit) {
                    byte[] buffer = new byte[mMinBufferSize];                     int ret = mAudioRecord.read(byte, 0, mMinBufferSize);                                 if (ret == AudioRecord.ERROR_INVALID_OPERATION) {                        Log.e(TAG, "Error ERROR_INVALID_OPERATION");                    } else if (ret == AudioRecord.ERROR_BAD_VALUE) {                        Log.e(TAG, "Error ERROR_BAD_VALUE");                    } else {                    }                }            }catch (Exception e){                e.printStackTrace();            }
        }    }

mIsLoopExit = true;if (mAudioRecord.getRecordingState() == AudioRecord.RECORDSTATE_RECORDING) {            mAudioRecord.stop();}mAudioRecord.release();

AudioTrack(int streamType, int sampleRateInHz, int channelConfig, int audioFormat, int bufferSizeInBytes, int mode)

AudioTrack.getMinBufferSize(sampleRateInHz,channelConfig,audioFormat);

 if (mAudioTrack.getState() == AudioTrack.STATE_UNINITIALIZED) {            Log.e(TAG, "AudioTrack initialize fail !");            return false;        }

    private class AudioPlayerRunnable implements Runnable {
        @RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)        @Override        public void run() {            try {                while (!mIsLoopExit) {                // mByteBuffer为要写入的数据                    mByteBuffer.rewind();                    int ret = mAudioTrack.write(mByteBuffer, num, AudioTrack.WRITE_BLOCKING);                    if ( ret < 0) {                        Log.e(TAG, "audiotrack write data fial %d :"+ ret);                        mIsLoopExit = true;                        continue;                    }                    mAudioTrack.play();                    Log.d(TAG , "OK, Played "+ret+" bytes !");                    mByteBuffer.clear();                }
            } catch (Exception e)            {                e.printStackTrace();            }        }    }

 mIsLoopExit = false; if (mAudioTrack.getPlayState() == AudioTrack.PLAYSTATE_PLAYING) { mAudioTrack.stop(); }
mAudioTrack.release();

static MediaCodec createDecoderByType (String type);static MediaCodec   createEncoderByType(String type);static MediaCodec   createByCodecName(String name);

//第二个参数是设置surface，用来在其上绘制解码器解码出的数据；第三个参数于数据加密有关；第四个参数上1表示编码器，0是否表示解码器呢void    configure(MediaFormat format, Surface surface, MediaCrypto crypto, int flags);

void    start()

int dequeueInputBuffer(long timeoutUs);

void    queueInputBuffer(int index, int offset, int size, long presentationTimeUs, int flags)

MediaCodec.BufferInfo audioBufferInfo = new MediaCodec.BufferInfo();

int dequeueOutputBuffer(MediaCodec.BufferInfo info, long timeoutUs)

ByteBuffer  getOutputBuffer(int index);int dequeueOutputBuffer(MediaCodec.BufferInfo info, long timeoutUs)

void    releaseOutputBuffer(int index, boolean render)

void    flush();void    stop();void    release();

MediaCodecList list = new MediaCodecList(MediaCodecList.REGULAR_CODECS);//REGULAR_CODECS参考api说明MediaCodecInfo[] codecs = list.getCodecInfos();Log.d(TAG, "Decoders: ");for (MediaCodecInfo codec : codecs) {    if (codec.isEncoder())        continue;    Log.d(TAG, codec.getName());}Log.d(TAG, "Encoders: ");for (MediaCodecInfo codec : codecs) {    if (codec.isEncoder())        Log.d(TAG, codec.getName());}

setDataSource(String path)：即可以设置本地文件又可以设置网络文件getTrackCount()：得到源文件通道数getTrackFormat(int index)：获取指定（index）的通道格式//选定特定的轨道，会影响 readSampleData(ByteBuffer, int), getSampleTrackIndex() and getSampleTime()的输出，这三个函数输出的是选定轨道的信息selectTrack(int index)unselectTrack(int index)getSampleTime()：返回当前的时间戳readSampleData(ByteBuffer byteBuf, int offset)：把指定通道中的数据按偏移量读取到ByteBuffer中；advance()：读取下一帧数据release(): 读取结束后释放资源seekTo(long timeUs, int mode): seek到指定位置

 MediaExtractor extractor = new MediaExtractor(); extractor.setDataSource(...); //设置源 int numTracks = extractor.getTrackCount();  //获取track个数 for (int i = 0; i < numTracks; ++i) {   MediaFormat format = extractor.getTrackFormat(i); //得到track格式   String mime = format.getString(MediaFormat.KEY_MIME);   if (weAreInterestedInThisTrack) {     extractor.selectTrack(i);  //选取感兴趣的track   } } ByteBuffer inputBuffer = ByteBuffer.allocate(...) while (extractor.readSampleData(inputBuffer, ...) >= 0) { //读取数据   int trackIndex = extractor.getSampleTrackIndex();     long presentationTimeUs = extractor.getSampleTime();   ...   extractor.advance(); //读取下一帧 }
 extractor.release(); //释放 extractor = null;

AudioManager audioManager = (AudioManager) mContext.getSystemService(Context.AUDIO_SERVICE); 

    public static final int STATE_DISCONNECTED  = 0;    /** The profile is in connecting state */    public static final int STATE_CONNECTING    = 1;    /** The profile is in connected state */    public static final int STATE_CONNECTED     = 2;    /** The profile is in disconnecting state */    public static final int STATE_DISCONNECTING = 3;

 /**     * Indicates the local Bluetooth adapter is off.     */    public static final int STATE_OFF = 10;    /**     * Indicates the local Bluetooth adapter is turning on. However local     * clients should wait for {@link #STATE_ON} before attempting to     * use the adapter.     */    public static final int STATE_TURNING_ON = 11;    /**     * Indicates the local Bluetooth adapter is on, and ready for use.     */    public static final int STATE_ON = 12;    /**     * Indicates the local Bluetooth adapter is turning off. Local clients     * should immediately attempt graceful disconnection of any remote links.     */

  /**     * Value for extra EXTRA_SCO_AUDIO_STATE or EXTRA_SCO_AUDIO_PREVIOUS_STATE     * indicating that the SCO audio channel is not established     */    public static final int SCO_AUDIO_STATE_DISCONNECTED = 0;    /**     * Value for extra {@link #EXTRA_SCO_AUDIO_STATE} or {@link #EXTRA_SCO_AUDIO_PREVIOUS_STATE}     * indicating that the SCO audio channel is established     */    public static final int SCO_AUDIO_STATE_CONNECTED = 1;    /**     * Value for extra EXTRA_SCO_AUDIO_STATE or EXTRA_SCO_AUDIO_PREVIOUS_STATE     * indicating that the SCO audio channel is being established     */    public static final int SCO_AUDIO_STATE_CONNECTING = 2;    /**     * Value for extra EXTRA_SCO_AUDIO_STATE indicating that     * there was an error trying to obtain the state     */    public static final int SCO_AUDIO_STATE_ERROR = -1;