我正在编写一个使用MediaCodec记录屏幕捕获和音频的应用程序.我使用MediaMuxer多媒体视频和音频来创建mp4文件.我成功地设法分别编写视频和音频,但是当我尝试将它们复制在一起时,结果是意想不到的.无论是音频播放还是视频播放,或者音频播放完毕.我的猜测是,我做错了时间戳,但我不知道究竟是什么.我已经看过这些例子： https://github.com/OnlyInAmerica/HWEncoderExperiments/tree/audiotest/HWEncoderExperiments/src/main/java/net/openwatch/hwencoderexperiments和bigflake.com上的那些,并没有找到答案.

以下是我的媒体格式配置：

mVideoFormat = createMediaFormat();

    private static MediaFormat createVideoFormat() {
    MediaFormat format = MediaFormat.createVideoFormat(
            Preferences.MIME_TYPE,mScreenWidth,mScreenHeight);
    format.setInteger(MediaFormat.KEY_COLOR_FORMAT,MediaCodecInfo.CodecCapabilities.COLOR_FormatSurface);
    format.setInteger(MediaFormat.KEY_BIT_RATE,Preferences.BIT_RATE);
    format.setInteger(MediaFormat.KEY_FRAME_RATE,Preferences.FRAME_RATE);
    format.setInteger(MediaFormat.KEY_I_FRAME_INTERVAL,Preferences.IFRAME_INTERVAL);
    return format;
}
    mAudioFormat = createAudioFormat();

    private static MediaFormat createAudioFormat() {
    MediaFormat format = new MediaFormat();
    format.setString(MediaFormat.KEY_MIME,"audio/mp4a-latm");
    format.setInteger(MediaFormat.KEY_AAC_PROFILE,MediaCodecInfo.CodecProfileLevel.AACObjectLC);
    format.setInteger(MediaFormat.KEY_SAMPLE_RATE,44100);
    format.setInteger(MediaFormat.KEY_CHANNEL_COUNT,1);
    format.setInteger(MediaFormat.KEY_BIT_RATE,64000);
    return format;
}

音视频编码器,复用器：

mVideoEncoder = MediaCodec.createEncoderByType(Preferences.MIME_TYPE);
    mVideoEncoder.configure(mVideoFormat,null,MediaCodec.CONFIGURE_FLAG_ENCODE);
    mInputSurface = new InputSurface(mVideoEncoder.createInputSurface(),mSavedEglContext);
    mVideoEncoder.start();
    if (recordAudio){
        audioBufferSize = AudioRecord.getMinBufferSize(44100,AudioFormat.CHANNEL_CONFIGURATION_MONO,AudioFormat.ENCODING_PCM_16BIT);
        mAudioRecorder = new AudioRecord(MediaRecorder.AudioSource.MIC,44100,AudioFormat.ENCODING_PCM_16BIT,audioBufferSize);
        mAudioRecorder.startRecording();

        mAudioEncoder = MediaCodec.createEncoderByType("audio/mp4a-latm");
        mAudioEncoder.configure(mAudioFormat,MediaCodec.CONFIGURE_FLAG_ENCODE);
        mAudioEncoder.start();
    }
    try {
        String fileId = String.valueOf(System.currentTimeMillis());
        mMuxer = new MediaMuxer(dir.getPath() + "/Video"
                + fileId + ".mp4",MediaMuxer.OutputFormat.MUXER_OUTPUT_MPEG_4);
    } catch (IOException ioe) {
        throw new RuntimeException("MediaMuxer creation Failed",ioe);
    }
    mVideoTrackIndex = -1;
    mAudioTrackIndex = -1;
    mMuxerStarted = false;

我用它设置视频时间戳：

mInputSurface.setPresentationTime(mSurfaceTexture.getTimestamp());
drainVideoEncoder(false);

并设置音频时间戳：

lastQueuedPresentationTimeStampUs = getNextQueuedPresentationTimeStampUs();

if(endOfStream)
    mAudioEncoder.queueInputBuffer(inputBufferIndex,audioBuffer.length,lastQueuedPresentationTimeStampUs,MediaCodec.BUFFER_FLAG_END_OF_STREAM);
 else
     mAudioEncoder.queueInputBuffer(inputBufferIndex,0);


  mAudioBufferInfo.presentationTimeUs = getNextDeQueuedPresentationTimeStampUs();
  mMuxer.writeSampleData(mAudioTrackIndex,encodedData,mAudioBufferInfo);
  lastDequeuedPresentationTimeStampUs = mAudioBufferInfo.presentationTimeUs;


  private static long getNextQueuedPresentationTimeStampUs(){
    long nextQueuedPresentationTimeStampUs = (lastQueuedPresentationTimeStampUs > lastDequeuedPresentationTimeStampUs) 
            ? (lastQueuedPresentationTimeStampUs + 1) : (lastDequeuedPresentationTimeStampUs + 1);
    Log.i(TAG,"nextQueuedPresentationTimeStampUs: " + nextQueuedPresentationTimeStampUs);
    return nextQueuedPresentationTimeStampUs;
}


private static long getNextDeQueuedPresentationTimeStampUs(){
    Log.i(TAG,"nextDequeuedPresentationTimeStampUs: " + (lastDequeuedPresentationTimeStampUs + 1));
    lastDequeuedPresentationTimeStampUs ++;
    return lastDequeuedPresentationTimeStampUs;
}

我从这个例子https://github.com/OnlyInAmerica/HWEncoderExperiments/blob/audiotest/HWEncoderExperiments/src/main/java/net/openwatch/hwencoderexperiments/AudioEncodingTest.java中拿出来,以避免“timestampUs XXX< lastTimestampUs XXX”错误 有人可以帮我弄清楚问题吗？