我尝试通过moviemaker合并多个MP4文件，就像我在一个帖子中看到的：

public class Main {

    public static void main(String[] args) throws IOException {
        MovieCreator mc = new MovieCreator();
        Movie movie1 = mc.build("./test1.mp4");
        Movie movie2 = mc.build("./test2.mp4");

        //Fetching the video tracks from the movies and storing them into an array
        Track[] vetTrackVideo = new Track[0];
        vetTrackVideo = Stream.of(movie1, movie2)
                .flatMap(movie -> movie.getTracks().stream())
                .filter(movie -> movie.getHandler().equals("vide"))
                .collect(Collectors.toList())
                .toArray(vetTrackVideo);

        //Fetching the audio tracks from the movies and storing them into an array
        Track[] vetTrackAudio = new Track[0];
        vetTrackAudio = Stream.of(movie1, movie2)
                .flatMap(movie -> movie.getTracks().stream())
                .filter(movie -> movie.getHandler().equals("soun"))
                .collect(Collectors.toList())
                .toArray(vetTrackAudio);

        //Creating the output movie by setting a list with both video and audio tracks
        Movie movieOutput = new Movie();
        List<Track> listTracks = new ArrayList<>(List.of(new AppendTrack(vetTrackVideo), new AppendTrack(vetTrackAudio)));
        movieOutput.setTracks(listTracks);

        //Building the output movie and storing it into a Container
        DefaultMp4Builder mp4Builder = new DefaultMp4Builder();
        Container c = mp4Builder.build(movieOutput);

        //Writing the output file
        FileOutputStream fos = new FileOutputStream("output.mp4");
        c.writeContainer(fos.getChannel());
        fos.close();
    }
}

对于两个文件，这完全可以正常工作。但我有两个以上的文件要合并。所以我开始添加一个合并两个文件的循环，并使用合并的文件与另一个合并。理论上它的工作，我看到他们合并的时间戳。但我不能打开文件，因为它是一个带有avc1声音的mp4a ...有没有人知道如何解决它？下面的代码是我的尝试：只要选择一个包含一些mp4文件的目录，合并后的文件命名为output0，output1，2，...最大的数字是最终文件。但是当output0工作正常时，output1已经不工作了...

public void Merge(File folder){
      
        File[] liste = folder.listFiles();
        String path = jTextField1.getText();
        for(int i = 0; i < liste.length-2; i++){
            
      MovieCreator mc = new MovieCreator();
      try{
        Movie movie1 = mc.build(liste[i].toString());
          System.out.println("Film 1: " + liste[i]);
        Movie movie2 = mc.build(liste[i+1].toString());
          System.out.println("Film 2: " + liste[i+1]);
          
        //Fetching the video tracks from the movies and storing them into an array
        Track[] vetTrackVideo = new Track[0];
        vetTrackVideo = Stream.of(movie1, movie2)
                .flatMap(movie -> movie.getTracks().stream())
                .filter(movie -> movie.getHandler().equals("vide"))
                .collect(Collectors.toList())
                .toArray(vetTrackVideo);

        //Fetching the audio tracks from the movies and storing them into an array
        Track[] vetTrackAudio = new Track[0];
        vetTrackAudio = Stream.of(movie1, movie2)
                .flatMap(movie -> movie.getTracks().stream())
                .filter(movie -> movie.getHandler().equals("soun"))
                .collect(Collectors.toList())
                .toArray(vetTrackAudio);

        //Creating the output movie by setting a list with both video and audio tracks
        Movie movieOutput = new Movie();
        List<Track> listTracks = new ArrayList<>(List.of(new AppendTrack(vetTrackVideo), new AppendTrack(vetTrackAudio)));
        movieOutput.setTracks(listTracks);

        //Building the output movie and storing it into a Container
        DefaultMp4Builder mp4Builder = new DefaultMp4Builder();
        Container c = (Container) mp4Builder.build(movieOutput);

        //Writing the output file
        FileOutputStream fos = new FileOutputStream(path + "\\output" + i + ".mp4");
        c.writeContainer(fos.getChannel());
        fos.close();
        File f = new File(path + "\\output" + i + ".mp4");
        liste[i+1] = f;
              }catch(Exception e2){
          e2.printStackTrace();
      }
    }
  }