AVVideoComposition не работает в iOS 8

Question

Я работаю над приложением, в котором я сочиняю видео и экспортирую в каталог. Он отлично работает в прошивке 7, но не в прошивке 8.

Ниже мой код:

AVAsset *pVideoTrack = [AVAsset assetWithURL:[NSURL fileURLWithPath:assetPath]]; 
AVVideoComposition *origionalComposition = [AVVideoComposition videoCompositionWithPropertiesOfAsset:pVideoTrack]; 

AVAssetTrack *clipVideoTrack = [[pVideoTrack tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0]; 

AVMutableComposition* mixComposition = [AVMutableComposition composition]; 
AVMutableCompositionTrack *compositionVideoTrack = [mixComposition addMutableTrackWithMediaType:AVMediaTypeVideo preferredTrackID:kCMPersistentTrackID_Invalid]; 
[compositionVideoTrack insertTimeRange:CMTimeRangeMake(kCMTimeZero, pVideoTrack.duration) 
           ofTrack:clipVideoTrack 
           atTime:kCMTimeZero error:nil]; 
[compositionVideoTrack setPreferredTransform:[[[pVideoTrack tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0] preferredTransform]]; 

BOOL bIsPotrait = [self checkVideoOrientationProperty:[[pVideoTrack tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0]]; 

CGSize videoSize = CGSizeMake(0, 0); 
if(bIsPotrait) 
    videoSize = CGSizeMake([[[pVideoTrack tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0] naturalSize].height, [[[pVideoTrack tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0] naturalSize].width); 

else 
    videoSize = [[[pVideoTrack tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0] naturalSize]; 

AVMutableVideoComposition* videoComp = [AVMutableVideoComposition videoComposition]; 
videoComp.renderSize = videoSize; 

AVAssetTrack *videoTrack = [[mixComposition tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0]; 
AVMutableVideoCompositionLayerInstruction* layerInstruction = [AVMutableVideoCompositionLayerInstruction videoCompositionLayerInstructionWithAssetTrack:videoTrack]; 

[layerInstruction setTransform:clipVideoTrack.preferredTransform atTime:kCMTimeZero]; 

AVMutableVideoCompositionInstruction *instruction = [AVMutableVideoCompositionInstruction videoCompositionInstruction]; 
instruction.layerInstructions = [NSArray arrayWithObject:layerInstruction]; 
instruction.timeRange = CMTimeRangeMake(kCMTimeZero, [mixComposition duration]); 

videoComp.instructions = [NSArray arrayWithObject: instruction]; 

videoComp.frameDuration = origionalComposition.frameDuration; 
videoComp.animationTool = [AVVideoCompositionCoreAnimationTool videoCompositionCoreAnimationToolWithPostProcessingAsVideoLayer:videoLayer inLayer:animatedWaterMarkLayer]; 

_assetExport = [[AVAssetExportSession alloc] initWithAsset:mixComposition presetName:AVAssetExportPresetMediumQuality]; 
    _assetExport.videoComposition = videoComp; 

NSString *CasheDirectory = [UICommonMethods GetLibraryCacheDirectoryPath]; 
NSString *outputPath = [CasheDirectory stringByAppendingPathComponent:kWatermarkVideoName]; 
NSURL *exportUrl = [NSURL fileURLWithPath:outputPath]; 

if ([[NSFileManager defaultManager] fileExistsAtPath:outputPath]) 
    [[NSFileManager defaultManager] removeItemAtPath:outputPath error:nil]; 

_assetExport.outputFileType = AVFileTypeQuickTimeMovie; 
_assetExport.outputURL = exportUrl; 
_assetExport.shouldOptimizeForNetworkUse = NO; 

[_assetExport exportAsynchronouslyWithCompletionHandler:^ 
{ 
    dispatch_async(dispatch_get_main_queue(), ^{ 

     switch ([_assetExport status]) { 
      case AVAssetExportSessionStatusExporting: 
       NSLog(@"Export in progress "); 
      case AVAssetExportSessionStatusFailed: 
       NSLog(@"Export failed (%d): %@", [[_assetExport error] code], [[_assetExport error] localizedFailureReason]); 
       [_assetExport cancelExport]; 
       break; 
      case AVAssetExportSessionStatusCancelled: 
       NSLog(@"Export canceled"); 
       break; 
      case AVAssetExportSessionStatusCompleted: 
       NSLog(@"Export done"); 
       NSLog (@"finished writing %f", [dtStartDate timeIntervalSinceNow]); 
       break; 
      case AVAssetExportSessionStatusWaiting: 
       NSLog (@"AVAssetExportSessionStatusWaiting"); 
       break; 
      case AVAssetExportSessionStatusUnknown: 
       NSLog (@"AVAssetExportSessionStatusUnknown"); 
       break; 
     } 

    }); 


}]; 

Это дает «Данные средства массовой информации не может быть расшифровано Это может быть повреждено.». Ошибка во время работы на прошивке 8.

Answer 1

Попробуйте это:

AVAssetExportSession* _assetExport = [[AVAssetExportSession alloc] initWithAsset:mixComposition 
                     presetName:AVAssetExportPresetPassthrough];