Problem beim Ausschneiden mehrerer Clips aus einem Film mit mp4parser-Bibliothek

Question

Ich benutze mp4parser Library zum Ausschneiden mehrerer Clips aus einem aufgenommenen Video. Es funktioniert gut, wenn ich einen Teil aus dem Video schneiden. Aber wenn ich versuche, mehrere Clips vom Video zu schneiden, wird der erste Clip richtig geschnitten. Andere sind nur 0 oder 1 Sekunde. Im Folgenden ist der My-Code:

import android.app.ProgressDialog; 
import android.content.Context; 
import android.os.Handler; 
import android.os.Message; 
import android.util.Log; 
import android.widget.Toast; 

import com.coremedia.iso.IsoFile; 
import com.coremedia.iso.boxes.TimeToSampleBox; 
import com.googlecode.mp4parser.authoring.Movie; 
import com.googlecode.mp4parser.authoring.Track; 
import com.googlecode.mp4parser.authoring.builder.DefaultMp4Builder; 
import com.googlecode.mp4parser.authoring.container.mp4.MovieCreator; 
import com.googlecode.mp4parser.authoring.tracks.CroppedTrack; 

import java.io.File; 
import java.io.FileInputStream; 
import java.io.FileNotFoundException; 
import java.io.FileOutputStream; 
import java.io.IOException; 
import java.nio.channels.FileChannel; 
import java.text.SimpleDateFormat; 
import java.util.ArrayList; 
import java.util.Arrays; 
import java.util.Date; 
import java.util.LinkedList; 
import java.util.List; 
import java.util.concurrent.ExecutorService; 
import java.util.concurrent.Executors; 

import uk.org.humanfocus.hfi.Beans.TrimPoint; 
import uk.org.humanfocus.hfi.Utils.Constants; 
import uk.org.humanfocus.hfi.Utils.SimpleThreadFactory; 
import uk.org.humanfocus.hfi.Utils.Ut; 

/** 
* Shortens/Crops a track 
*/ 
public class ShortenExample { 

    private static final String TAG = "ShortenExample"; 
    private final Context mCxt; 
    private ExecutorService mThreadExecutor = null; 
    private SimpleInvalidationHandler mHandler; 
    private ProgressDialog mProgressDialog; 
    String filePath; 
    ArrayList<TrimPoint> mTrimPoints; 
    int videoLength; 
    ArrayList<String> trimVideos; 
    private class SimpleInvalidationHandler extends Handler { 

     @Override 
     public void handleMessage(final Message msg) { 
      switch (msg.what) { 
      case R.id.shorten: 
       mProgressDialog.dismiss(); 

       if (msg.arg1 == 0) 
        Toast.makeText(mCxt, 
          mCxt.getString(R.string.message_error) + " " + (String) msg.obj, 
          Toast.LENGTH_LONG).show(); 
       else 
        Toast.makeText(mCxt, 
          mCxt.getString(R.string.message_shortened) + " " + (String) msg.obj, 
          Toast.LENGTH_LONG).show(); 
       break; 
      } 
     } 
    } 

    public ShortenExample(Context context) { 
     mCxt = context; 
     mHandler = new SimpleInvalidationHandler(); 
     //mProgressDialog = new ProgressDialog(mCxt); 
     //mProgressDialog.setMessage("Wait Saving.."); 
     //mProgressDialog.setCancelable(false); 
    } 

    public void shorten(String filePath,ArrayList<TrimPoint> trimPoints, int endTime) { 
     trimVideos = new ArrayList<String>(); 
     this.filePath = filePath; 
     this.videoLength = endTime; 
     this.mTrimPoints = trimPoints; 
     Log.d(Constants.TAG,"End Time: "+endTime+" Trim Points: "+mTrimPoints.size()); 
     for (int i=0;i<trimPoints.size();i++){ 
      TrimPoint point = trimPoints.get(i); 
      int start=0; 
      int end = 0; 
      if(point.getTime()-5<0){ 
       start = 0; 
      }else{ 
       start = point.getTime()-5; 
      } 

      if(point.getTime()+5>videoLength){ 
       end = videoLength-1; 
      }else { 
       end = point.getTime() + 5; 
      } 
      Log.d(Constants.TAG,"Clip: "+start+" : "+end); 
      doShorten(start,end); 
     } 
     Log.d(Constants.TAG,"Done: "+trimVideos.size()); 
    } 

    private void doShorten(final int _startTime, final int _endTime) { 
     //mProgressDialog = Ut.ShowWaitDialog(mCxt, 0); 

     //mProgressDialog.show(); 


     if(mThreadExecutor == null) 
      mThreadExecutor = Executors.newSingleThreadExecutor(new SimpleThreadFactory("doShorten")); 

     //this.mThreadExecutor.execute(new Runnable() { 
     // public void run() { 
       try { 
        File folder = Ut.getTestMp4ParserVideosDir(mCxt); 
        //File folder = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM),"HFVideos"+File.separator+"TEMP"); 
        //Log.d(Constants.TAG, folder.toString()); 
        if (!folder.exists()) { 
         Log.d(TAG, "failed to create directory"); 
        } 

        //Movie movie = new MovieCreator().build(new RandomAccessFile("/home/sannies/suckerpunch-distantplanet_h1080p/suckerpunch-distantplanet_h1080p.mov", "r").getChannel()); 
//     Movie movie = MovieCreator.build(new FileInputStream("/home/sannies/CSI.S13E02.HDTV.x264-LOL.mp4").getChannel()); 
        Movie movie = MovieCreator.build(new FileInputStream(new File(filePath)).getChannel()); 
        //Log.d(Constants.TAG,"Movie: "+movie.toString()); 
        List<Track> tracks = movie.getTracks(); 
        movie.setTracks(new LinkedList<Track>()); 
        // remove all tracks we will create new tracks from the old 

        double startTime = _startTime; 
        double endTime = _endTime;//(double) getDuration(tracks.get(0))/tracks.get(0).getTrackMetaData().getTimescale(); 

        boolean timeCorrected = false; 

        // Here we try to find a track that has sync samples. Since we can only start decoding 
        // at such a sample we SHOULD make sure that the start of the new fragment is exactly 
        // such a frame 
        for (Track track : tracks) { 
         if (track.getSyncSamples() != null && track.getSyncSamples().length > 0) { 
          if (timeCorrected) { 
           // This exception here could be a false positive in case we have multiple tracks 
           // with sync samples at exactly the same positions. E.g. a single movie containing 
           // multiple qualities of the same video (Microsoft Smooth Streaming file) 

           throw new RuntimeException("The startTime has already been corrected by another track with SyncSample. Not Supported."); 
          } 
          startTime = correctTimeToSyncSample(track, startTime, false); 
          endTime = correctTimeToSyncSample(track, endTime, true); 
          timeCorrected = true; 
         } 
        } 

        for (Track track : tracks) { 
         long currentSample = 0; 
         double currentTime = 0; 
         long startSample = -1; 
         long endSample = -1; 

         for (int i = 0; i < track.getDecodingTimeEntries().size(); i++) { 
          TimeToSampleBox.Entry entry = track.getDecodingTimeEntries().get(i); 
          for (int j = 0; j < entry.getCount(); j++) { 
           // entry.getDelta() is the amount of time the current sample covers. 

           if (currentTime <= startTime) { 
            // current sample is still before the new starttime 
            startSample = currentSample; 
           } 
           if (currentTime <= endTime) { 
            // current sample is after the new start time and still before the new endtime 
            endSample = currentSample; 
           } else { 
            // current sample is after the end of the cropped video 
            break; 
           } 
           currentTime += (double) entry.getDelta()/(double) track.getTrackMetaData().getTimescale(); 
           currentSample++; 
          } 
         } 
         movie.addTrack(new CroppedTrack(track, startSample, endSample)); 
        } 
        long start1 = System.currentTimeMillis(); 
        IsoFile out = new DefaultMp4Builder().build(movie); 
        long start2 = System.currentTimeMillis(); 

//     FileOutputStream fos = new FileOutputStream(String.format("output-%f-%f.mp4", startTime, endTime)); 
        String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date()); 
        String filename = folder.getPath() + File.separator + String.format("TMP4_APP_OUT-%f-%f", startTime, endTime) + "_" + timeStamp + ".mp4"; 
        trimVideos.add(filename); 
        FileOutputStream fos = new FileOutputStream(filename); 

        FileChannel fc = fos.getChannel(); 
        out.getBox(fc); 
        fc.close(); 
        fos.close(); 
        long start3 = System.currentTimeMillis(); 
        System.err.println("Building IsoFile took : " + (start2 - start1) + "ms"); 
        System.err.println("Writing IsoFile took : " + (start3 - start2) + "ms"); 
        System.err.println("Writing IsoFile speed : " + (new File(String.format("TMP4_APP_OUT-%f-%f", startTime, endTime)).length()/(start3 - start2)/1000) + "MB/s"); 

        Message.obtain(mHandler, R.id.shorten, 1, 0, filename).sendToTarget(); 
       } catch (FileNotFoundException e) { 
        Message.obtain(mHandler, R.id.shorten, 0, 0, e.getMessage()).sendToTarget(); 
        e.printStackTrace(); 
       } catch (IOException e) { 
        Message.obtain(mHandler, R.id.shorten, 0, 0, e.getMessage()).sendToTarget(); 
        e.printStackTrace(); 
       } 
       //mProgressDialog.dismiss(); 
     // } 
     //}); 

    } 

    protected static long getDuration(Track track) { 
     long duration = 0; 
     for (TimeToSampleBox.Entry entry : track.getDecodingTimeEntries()) { 
      duration += entry.getCount() * entry.getDelta(); 
     } 
     return duration; 
    } 

    private static double correctTimeToSyncSample(Track track, double cutHere, boolean next) { 
     double[] timeOfSyncSamples = new double[track.getSyncSamples().length]; 
     long currentSample = 0; 
     double currentTime = 0; 
     for (int i = 0; i < track.getDecodingTimeEntries().size(); i++) { 
      TimeToSampleBox.Entry entry = track.getDecodingTimeEntries().get(i); 
      for (int j = 0; j < entry.getCount(); j++) { 
       if (Arrays.binarySearch(track.getSyncSamples(), currentSample + 1) >= 0) { 
        // samples always start with 1 but we start with zero therefore +1 
        timeOfSyncSamples[Arrays.binarySearch(track.getSyncSamples(), currentSample + 1)] = currentTime; 
       } 
       currentTime += (double) entry.getDelta()/(double) track.getTrackMetaData().getTimescale(); 
       currentSample++; 
      } 
     } 
     double previous = 0; 
     for (double timeOfSyncSample : timeOfSyncSamples) { 
      if (timeOfSyncSample > cutHere) { 
       if (next) { 
        return timeOfSyncSample; 
       } else { 
        return previous; 
       } 
      } 
      previous = timeOfSyncSample; 
     } 
     return timeOfSyncSamples[timeOfSyncSamples.length - 1]; 
    } 


} 

Answer 1

Das Problem war nur in Emulator. Wenn wir Video im Emulator aufnehmen, werden weniger Sekunden als die tatsächliche Zeit aufgezeichnet. Der Code arbeitet mit dem tatsächlichen Gerät in Ordnung.

Answer 2

BTW, für die Dauer in Sekunden müssen Sie durch die Zeitskala dividieren. Ich finde, dass die Anzahl der Einträge (oder Stichproben) zwischen Audio- und Videospuren gleicher Dauer variiert. Aber ich bin ein totaler Noob, hör mir nicht zu.

protected static double getDuration(Track track) { 
    double duration = 0; 
    for (TimeToSampleBox.Entry entry : track.getDecodingTimeEntries()) { 
     duration += entry.getCount() * entry.getDelta()/(double) track.getTrackMetaData().getTimescale(); 
    } 
    return duration; 
}