title: Not able to save .mp4 video to camera roll
body: <p>I have am iOS DVR application where i record and save video in .mp4 format in the document directory. 
  I am trying to move that video to camera roll but i am not able to move it. 
  I think it might be because of video format. Below is format of the video
  H264 - MPEG-4 AVC
  Resolution: 352 x 258
  Frame rate: 15 </p>
  
  <p>I tried UISaveVideoAtPathToSavedPhotosAlbum but no luck. </p>
  
  <p>I also tried to convert the video to another .mp4 using asset library using following code but status is always Failed. </p>
  
  <pre><code> [self convertVideoToLowQuailtyWithInputURL:localUrl outputURL:outputURL handler:^(AVAssetExportSession *exportSession)
  {
      if (exportSession.status == AVAssetExportSessionStatusCompleted) {
          // Video conversation completed
      }          
  }];
  
  - (void)convertVideoToLowQuailtyWithInputURL:(NSURL*)inputURL outputURL:(NSURL*)outputURL handler:(void (^)(AVAssetExportSession*))handler {
      [[NSFileManager defaultManager] removeItemAtURL:outputURL error:nil];
      AVURLAsset *asset = [AVURLAsset URLAssetWithURL:inputURL options:nil];
      AVAssetExportSession *exportSession = [[AVAssetExportSession alloc] initWithAsset:asset presetName:AVAssetExportPresetPassthrough];
      exportSession.outputURL = outputURL;
      exportSession.outputFileType = AVFileTypeMPEG4;
      [exportSession exportAsynchronouslyWithCompletionHandler:^(void) {
           handler(exportSession);
       }];
  }
  </code></pre>
  
  <p>How can I save recorded video file to camera roll ? </p>