Question

我正致力于合并视频功能。

在我的应用程序中，我有一个带有多个轨道的视频（总共10个轨道9个视频轨道和一个音轨很常见）。现在我想从这个多轨道获得3个视频。第一个视频与1,4,7轨道相结合第二个视频与2,5,8轨道和第三个视频与3,6,9轨道相结合音频轨道对于这三个视频很常见。

我想使用以下代码执行此操作。

 AVPlayerItem* playerItem = [AVPlayerItem playerItemWithURL:[NSURL fileURLWithPath:urlSubItem.path]];
 NSLog(@"%@",playerItem);
 NSArray* arrTracks = [playerItem.asset tracksWithMediaType:AVMediaTypeVideo];

 NSLog(@"%@",arrTracks);
 NSArray* arrTracksText = [playerItem.asset tracksWithMediaType:AVMediaTypeText];
 NSArray* arrTracksAudio = [playerItem.asset tracksWithMediaType:AVMediaTypeAudio];
 NSLog(@"%@:%@",arrTracks,arrTracksAudio);
 for (int i=0; i<3; i++) {
     AVMutableComposition* mixComposition = [AVMutableComposition composition];
     AVMutableCompositionTrack *compositionCommentaryTrack = [mixComposition addMutableTrackWithMediaType:AVMediaTypeAudio                                                         preferredTrackID:kCMPersistentTrackID_Invalid];
     [compositionCommentaryTrack insertTimeRange:CMTimeRangeMake(kCMTimeZero, playerItem.asset.duration) ofTrack:[[playerItem.asset tracksWithMediaType:AVMediaTypeAudio] objectAtIndex:0] atTime:kCMTimeZero error:nil];

     CMTime currentTime = kCMTimeZero;
     for (int k=0;k<[arrTracks count];k++) {
          NSLog(@"%d",k%3);
          if(k%3==i){
              AVAssetTrack* trackCombineVideo = [arrTracks objectAtIndex:k];    
              AVMutableCompositionTrack *compositionVideoTrack = [mixComposition addMutableTrackWithMediaType:AVMediaTypeVideo                                                                              preferredTrackID:kCMPersistentTrackID_Invalid];
              NSError* errors;
              [compositionVideoTrack insertTimeRange:CMTimeRangeMake(currentTime, trackCombineVideo.timeRange.duration)  ofTrack:[arrTracks objectAtIndex:k] atTime:currentTime error:&errors];
               if (errors) {
                   NSLog(@"wait error:%@",errors);
               }
               currentTime = trackCombineVideo.timeRange.duration;
            }
        }

         AVAssetExportSession* _assetExport = [[AVAssetExportSession alloc] initWithAsset:mixComposition presetName:AVAssetExportPresetPassthrough];
        _assetExport.outputFileType = @"com.apple.quicktime-movie";
        NSLog(@"file type %@",_assetExport.outputFileType);
        _assetExport.outputURL = exportUrl // Document Directory Path;
       _assetExport.shouldOptimizeForNetworkUse = YES;

使用此代码创建3个单独的视频，但每个视频都有3个不同的曲目。现在，我的问题是如何只用一个曲目创建视频？

Answer 1

 AVMutableCompositionTrack *compositionVideoTrack = [mixComposition
 addMutableTrackWithMediaType:AVMediaTypeVideo preferredTrackID:kCMPersistentTrackID_Invalid];

 for (int k=0;k<[arrTracks count];k++) {
      NSLog(@"%d",k%3);
      if(k%3==i){
          AVAssetTrack* trackCombineVideo = [arrTracks objectAtIndex:k];    

          [compositionVideoTrack insertTimeRange:CMTimeRangeMake(currentTime, trackCombineVideo.timeRange.duration)  ofTrack:[arrTracks objectAtIndex:k] atTime:currentTime error:&errors];
           if (errors) {
               NSLog(@"wait error:%@",errors);
           }
           currentTime = trackCombineVideo.timeRange.duration;
        }
    }

     AVAssetExportSession* _assetExport = [[AVAssetExportSession alloc] initWithAsset:mixComposition presetName:AVAssetExportPreset1280x720];
    _assetExport.outputFileType = @"com.apple.quicktime-movie";
    NSLog(@"file type %@",_assetExport.outputFileType);
    _assetExport.outputURL = exportUrl // Document Directory Path;
   _assetExport.shouldOptimizeForNetworkUse = YES;
   _assetExport.timeRange = CMTimeRangeMake(kCMTimeZero, playerItem.asset.duration);

合并视频无法在iOS应用中使用

1 个答案: