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MediaExtractor ? MediaMuxer ?????

MediaExtractor ?????

MediaExtractor ???????????????????????????????????????

MediaMuxer ?????

MediaMuxer ??????????????????????????????

????

????????????????

???? PTS

???? PTS ??????????????

????

???????????

?? 1??????

@TargetApi(Build.VERSION_CODES.JELLY_BEAN_MR2)public static void trackExtractor(String inPath, String outPath, boolean isVideo) {    MediaExtractor mediaExtractor = new MediaExtractor();    try {        mediaExtractor.setDataSource(inPath);    } catch (IOException e) {        e.printStackTrace();    }    MediaMuxer mediaMuxer = null;    try {        mediaMuxer = new MediaMuxer(outPath, MediaMuxer.OutputFormat.MUXER_OUTPUT_MPEG_4);    } catch (IOException e) {        e.printStackTrace();    }    int trackIndex = 0;    int trackCount = mediaExtractor.getTrackCount();    for (int i = 0; i < trackCount; i++) {        MediaFormat trackFormat = mediaExtractor.getTrackFormat(i);        String mime = trackFormat.getString(MediaFormat.KEY_MIME);        if (mime.startsWith("video/") && isVideo) {            trackIndex = mediaMuxer.addTrack(trackFormat);            mediaExtractor.selectTrack(i);            break;        } else if (mime.startsWith("audio/") && !isVideo) {            trackIndex = mediaMuxer.addTrack(trackFormat);            mediaExtractor.selectTrack(i);            break;        }    }    mediaMuxer.start();    ByteBuffer buffer = ByteBuffer.allocate(1024 * 1000);    MediaCodec.BufferInfo bufferInfo = new MediaCodec.BufferInfo();    long videoSampleTime = getSampleTime(mediaExtractor, buffer);    while (true) {        int readSampleDataSize = mediaExtractor.readSampleData(buffer, 0);        if (readSampleDataSize < 0) {            break;        }        bufferInfo.size = readSampleDataSize;        bufferInfo.offset = 0;        bufferInfo.flags = mediaExtractor.getSampleFlags();        bufferInfo.presentationTimeUs += videoSampleTime;        mediaMuxer.writeSampleData(trackIndex, buffer, bufferInfo);        mediaExtractor.advance();    }    mediaExtractor.release();    mediaMuxer.stop();    mediaMuxer.release();}

?? 2??????

@TargetApi(Build.VERSION_CODES.JELLY_BEAN_MR2)public static void trackMuxer(String videoPath, String audioPath, String outPath) {    MediaExtractor videoExtractor = new MediaExtractor();    try {        videoExtractor.setDataSource(videoPath);    } catch (IOException e) {        e.printStackTrace();    }    MediaExtractor audioExtractor = new MediaExtractor();    try {        audioExtractor.setDataSource(audioPath);    } catch (IOException e) {        e.printStackTrace();    }    MediaMuxer mediaMuxer = null;    try {        mediaMuxer = new MediaMuxer(outPath, MediaMuxer.OutputFormat.MUXER_OUTPUT_MPEG_4);    } catch (IOException e) {        e.printStackTrace();    }    int videoTrackIndex = -1;    int audioTrackIndex = -1;    MediaFormat videoFormat = null;    MediaFormat audioFormat = null;    int videoTrackCount = videoExtractor.getTrackCount();    for (int i = 0; i < videoTrackCount; i++) {        videoFormat = videoExtractor.getTrackFormat(i);        String mime = videoFormat.getString(MediaFormat.KEY_MIME);        if (mime.startsWith("video/")) {            videoTrackIndex = i;            break;        }    }    int audioTrackCount = audioExtractor.getTrackCount();    for (int i = 0; i < audioTrackCount; i++) {        audioFormat = audioExtractor.getTrackFormat(i);        String mime = audioFormat.getString(MediaFormat.KEY_MIME);        if (mime.startsWith("audio/")) {            audioTrackIndex = i;            break;        }    }    videoExtractor.selectTrack(videoTrackIndex);    audioExtractor.selectTrack(audioTrackIndex);    MediaCodec.BufferInfo videoBufferInfo = new MediaCodec.BufferInfo();    MediaCodec.BufferInfo audioBufferInfo = new MediaCodec.BufferInfo();    ByteBuffer byteBuffer = ByteBuffer.allocate(1024 * 1000);    long videoSampleTime = getSampleTime(videoExtractor, byteBuffer);    while (true) {        int readVideoSampleSize = videoExtractor.readSampleData(byteBuffer, 0);        if (readVideoSampleSize < 0) {            break;        }        videoBufferInfo.size = readVideoSampleSize;        videoBufferInfo.presentationTimeUs += videoSampleTime;        videoBufferInfo.offset = 0;        videoBufferInfo.flags = videoExtractor.getSampleFlags();        mediaMuxer.writeSampleData(videoTrackIndex, byteBuffer, videoBufferInfo);        videoExtractor.advance();    }    long audioSampleTime = getSampleTime(audioExtractor, byteBuffer);    while (true) {        int readAudioSampleSize = audioExtractor.readSampleData(byteBuffer, 0);        if (readAudioSampleSize < 0) {            break;        }        audioBufferInfo.size = readAudioSampleSize;        audioBufferInfo.presentationTimeUs += audioSampleTime;        audioBufferInfo.offset = 0;        audioBufferInfo.flags = audioExtractor.getSampleFlags();        mediaMuxer.writeSampleData(audioTrackIndex, byteBuffer, audioBufferInfo);        audioExtractor.advance();    }    mediaMuxer.stop();    mediaMuxer.release();    videoExtractor.release();    audioExtractor.release();}

PTS ????

??????? PTS ??????

private static long getSampleTime(MediaExtractor mediaExtractor, ByteBuffer buffer) {    long videoSampleTime;    mediaExtractor.readSampleData(buffer, 0);    long firstVideoPTS = mediaExtractor.getSampleTime();    mediaExtractor.advance();    mediaExtractor.readSampleData(buffer, 0);    long secondVideoPTS = mediaExtractor.getSampleTime();    videoSampleTime = Math.abs(secondVideoPTS - firstVideoPTS);    return videoSampleTime;}

????????????????? PTS??????????????

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