mp4解析时间拍帧速率

我正在尝试摄取一个mp4文件并使其成为延时摄影。它适用于下面附带的代码。但是，输出文件的帧速率为 。由于我不打算将其作为视频播放，因此我宁愿删除这些冗余帧以使输出文件变小。16*originalFrameRateslow motion

Movie inputMovie = MovieCreator.build(fileUri);

List<Track> videoTracks = new LinkedList<>();

for (Track track : inputMovie.getTracks()) {
    if (track.getHandler().equals("vide")) {
        videoTracks.add(track);
    }
}

final int speedByFactorOf = 16;

Movie outputMovie = new Movie();

AppendTrack appendedTracks = new AppendTrack(videoTracks.toArray(new Track[videoTracks.size()]));
outputMovie.addTrack(new WrappingTrack(appendedTracks) {
    @Override
    public long[] getSampleDurations() {
        long[] l = super.getSampleDurations();
        for (int i = 0; i < l.length; i++) {
            l[i] /= speedByFactorOf;
        }
        return l;
    }
});

BasicContainer out = (BasicContainer) new DefaultMp4Builder().build(outputMovie);

FileChannel fc = new RandomAccessFile("timelapse.mp4", "rw").getChannel();
out.writeContainer(fc);
fc.close();
out.close();

我无法找到任何如何更改输出帧速率的示例。