camera2 opengl实现滤镜效果录制视频 三 录音

本来是想用MediaRecorder直接录像的，可是好像参数设置错误总是报错就改用MediaCodec了

MediaCodec配合MediaMuxer进行录音，以后可以直接用来录像

public class AudioEncoder {    private static final int CHANNEL_CONFIG = AudioFormat.CHANNEL_IN_MONO; //音频通道(单声道)    private static final int AUDIO_FORMAT = AudioFormat.ENCODING_PCM_16BIT; //音频格式    private static final int AUDIO_SOURCE = MediaRecorder.AudioSource.MIC; //音频源（麦克风）    private static final String AUDIO_MIME_TYPE = "audio/mp4a-latm"; //音频类型    private static final int SAMPLE_RATE = 44100; //采样率(CD音质)    private static final int BIT_RATE = 128000; //比特率    private static final int CHANNEL_COUNT = 1;//声道    private MediaCodec mAudioCodec; //音频编解码器    private MediaMuxer mMediaMuxer;    //初始化    public void initAudio() {        String path = "/storage/emulated/0/360/" + System.currentTimeMillis() + ".mp4";        MediaFormat mAudioFormat = new MediaFormat();        mAudioFormat.setString(MediaFormat.KEY_MIME, AUDIO_MIME_TYPE);        mAudioFormat.setInteger(MediaFormat.KEY_AAC_PROFILE, MediaCodecInfo.CodecProfileLevel.AACObjectLC);        mAudioFormat.setInteger(MediaFormat.KEY_SAMPLE_RATE, SAMPLE_RATE);        mAudioFormat.setInteger(MediaFormat.KEY_BIT_RATE, BIT_RATE);        mAudioFormat.setInteger(MediaFormat.KEY_CHANNEL_COUNT, CHANNEL_COUNT);        try {            mAudioCodec = MediaCodec.createEncoderByType(AUDIO_MIME_TYPE);            mAudioCodec.configure(mAudioFormat, null, null, MediaCodec.CONFIGURE_FLAG_ENCODE);            mAudioCodec.start();            mMediaMuxer = new MediaMuxer(path, MediaMuxer.OutputFormat.MUXER_OUTPUT_MPEG_4);        } catch (IOException e) {            e.printStackTrace();        }    }    private long audioStartTime;    //开始    public void start() {        //麦克风采集线程        Thread thread = new Thread() {            @Override            public void run() {                super.run();                int bufferSizeInBytes = AudioRecord.getMinBufferSize(SAMPLE_RATE, CHANNEL_CONFIG, AUDIO_FORMAT);                AudioRecord audioRecord = new AudioRecord(                        AUDIO_SOURCE,//音频源                        SAMPLE_RATE,//采样率                        CHANNEL_CONFIG,//音频通道                        AUDIO_FORMAT,//音频格式                        bufferSizeInBytes//缓冲区                );                if (audioRecord.getState() != AudioRecord.STATE_INITIALIZED) {                    //麦克风被占用                    return;                }                audioRecord.startRecording();                byte[] buffer = new byte[bufferSizeInBytes];                audioStartTime = System.nanoTime();                while (stop) {                    long audioPresentationTimeNs = System.nanoTime();                    int bufferReadResult = audioRecord.read(buffer, 0, bufferSizeInBytes);                    if (bufferReadResult == AudioRecord.ERROR_BAD_VALUE || bufferReadResult == AudioRecord.ERROR_INVALID_OPERATION) {                    }                    //向MediaCodec传数据                    audioInputBuffer(buffer, audioPresentationTimeNs, false);                }                long audioPresentationTimeNs = System.nanoTime();                int bufferReadResult = audioRecord.read(buffer, 0, bufferSizeInBytes);                if (bufferReadResult == AudioRecord.ERROR_BAD_VALUE || bufferReadResult == AudioRecord.ERROR_INVALID_OPERATION) {                }                audioInputBuffer(buffer, audioPresentationTimeNs, true);                audioRecord.stop();                audioRecord.release();            }        };        //编码线程        Thread t = new Thread() {            @Override            public void run() {                super.run();                offerAudioEncoder();            }        };        //相互独立的线程        t.start();        thread.start();    }    public void audioInputBuffer(byte[] buffer, long pts, boolean audioEnd) {        int inputBufferIndex = mAudioCodec.dequeueInputBuffer(-1);        if (inputBufferIndex >= 0) {            ByteBuffer inputBuffer = mAudioCodec.getInputBuffer(inputBufferIndex);            inputBuffer.clear();            inputBuffer.put(buffer);            long presentationTimeUs = (pts - audioStartTime) / 1000;            //MediaCodec接收数据            if (audioEnd) {                mAudioCodec.queueInputBuffer(inputBufferIndex, 0, buffer.length, presentationTimeUs, MediaCodec.BUFFER_FLAG_END_OF_STREAM);            } else {                mAudioCodec.queueInputBuffer(inputBufferIndex, 0, buffer.length, presentationTimeUs, 0);            }        }    }    private void offerAudioEncoder() {        int mTrackIndex = -1;        MediaCodec.BufferInfo mBufferInfo = new MediaCodec.BufferInfo();        while (true) {            //阻塞线程等待数据，时间100毫秒            int encoderIndex = mAudioCodec.dequeueOutputBuffer(mBufferInfo, 100);            if (encoderIndex == MediaCodec.INFO_TRY_AGAIN_LATER) {            } else if (encoderIndex == MediaCodec.INFO_OUTPUT_FORMAT_CHANGED) {                //开启MediaMuxer，因为只有录音所以只调用一次                MediaFormat mediaFormat = mAudioCodec.getOutputFormat();                mTrackIndex = mMediaMuxer.addTrack(mediaFormat);                mMediaMuxer.start();            } else if (encoderIndex < 0) {            } else {                //有数据时进入这里取当前数据                ByteBuffer encodedData = mAudioCodec.getOutputBuffer(encoderIndex);                if ((mBufferInfo.flags & MediaCodec.BUFFER_FLAG_CODEC_CONFIG) != 0) {                    mBufferInfo.size = 0;                }                //将数据写入mMediaMuxer，结束写入开始下次循环                if (mBufferInfo.size != 0) {                    encodedData.position(mBufferInfo.offset);                    encodedData.limit(mBufferInfo.offset + mBufferInfo.size);                    mMediaMuxer.writeSampleData(mTrackIndex, encodedData, mBufferInfo);                    mAudioCodec.releaseOutputBuffer(encoderIndex, false);                }                //判断是否是关闭录音                if ((mBufferInfo.flags & MediaCodec.BUFFER_FLAG_END_OF_STREAM) != 0) {                    break;      // out of while                }            }        }        //释放        release();    }    public void release() {        if (mAudioCodec != null) {            mAudioCodec.stop();            mAudioCodec.release();            mAudioCodec = null;        }        if (mMediaMuxer != null) {            mMediaMuxer.release();            mMediaMuxer = null;        }    }    private boolean stop = true;    //结束    public void stop() {        stop = false;    }}