AVMutableComposition - 导出错误的视频转换

时间:2017-07-16 10:19:58

标签: objective-c avmutablecomposition avurlasset

导出VideoAsset后:

问题:

  1. 视频方向不是原始转换
  2. 导出的视频图层似乎始终是风景
  3. 试图:

    1. 转换视频图层方向 - 旋转至原始方向
    2. 视频图层尺寸 - 使其全屏尺寸(按原始方向)
    3. 一些注意事项:

      • videoAsset的CGRect从一开始就相反。
      导出后

      after export, video transform is wrong,视频转换错误

      tried to rotate with no success for full size layer尝试旋转但没有成功完整尺寸图层

                  AVURLAsset*videoAsset = [[AVURLAsset alloc]initWithURL:url options:nil];
      
                  AVMutableComposition* mixComposition = [AVMixerBase compositionVideoTrackAssetUrl:videoAsset];
      
                  AVMutableVideoComposition *videoComposition=[AVMutableVideoComposition videoComposition];
                  videoComposition.frameDuration=CMTimeMake(1, 30); //frames per seconds
                  videoComposition.renderSize = videoAsset.naturalSize;
                  //videoComposition.renderScale = 1.0;
      
                  videoComposition.animationTool = [AVVideoCompositionCoreAnimationTool videoCompositionCoreAnimationToolWithPostProcessingAsVideoLayer:videoLayer inLayer:parentLayer];
      
      
        AVMutableCompositionTrack *videoTrack = [[mixComposition tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0]; //was AVAssetTrack *videoTrack
          AVMutableVideoCompositionLayerInstruction *layerInstruction = [self layerInstructionAfterFixingOrientationForAsset:videoAsset
                                                                                                                    forTrack:videoTrack   atTime:videoAsset.duration];
      
      
      
       AVMutableVideoCompositionLayerInstruction *layerInstruction =  [AVMutableVideoCompositionLayerInstruction  videoCompositionLayerInstructionWithAssetTrack:videoTrack];
          [layerInstruction setTransform:videoTrack.preferredTransform atTime:kCMTimeZero];
          [layerInstruction setOpacity:0.0 atTime:videoAsset.duration];
      
      
      
      
                   AVMutableVideoCompositionInstruction *instruction = [AVMutableVideoCompositionInstruction videoCompositionInstruction];
                      instruction.timeRange = CMTimeRangeMake(kCMTimeZero, [videoAsset duration]);
                      instruction.layerInstructions = [NSArray arrayWithObject:layerInstruction];
                      videoComposition.instructions = [NSArray arrayWithObject:instruction];
      

      设置曲目

                  +(AVMutableComposition *)compositionVideoTrackAssetUrl:(AVURLAsset*)assetUrl{
      
                      AVMutableComposition* mixComposition = [AVMutableComposition composition];
                      AVMutableCompositionTrack *compositionVideoTrack = [mixComposition addMutableTrackWithMediaType:AVMediaTypeVideo preferredTrackID:kCMPersistentTrackID_Invalid];
                      AVMutableCompositionTrack *compositionAudioTrack = [mixComposition addMutableTrackWithMediaType:AVMediaTypeAudio preferredTrackID:kCMPersistentTrackID_Invalid];
      
      
                      AVAssetTrack *clipVideoTrack = [[assetUrl tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0];
                      AVAssetTrack *clipAudioTrack = [[assetUrl tracksWithMediaType:AVMediaTypeAudio] objectAtIndex:0];
                      [compositionVideoTrack insertTimeRange:CMTimeRangeMake(kCMTimeZero, assetUrl.duration) ofTrack:clipVideoTrack atTime:kCMTimeZero error:nil];
                      [compositionAudioTrack insertTimeRange:CMTimeRangeMake(kCMTimeZero, assetUrl.duration) ofTrack:clipAudioTrack atTime:kCMTimeZero error:nil];
                      [compositionVideoTrack setPreferredTransform:[[[assetUrl tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0] preferredTransform]];
                      return mixComposition;
                  }
      
      
      so after researching all stack overflow discussions about export rotation,
      I'm still having video rotation to size issue...
      

1 个答案:

答案 0 :(得分:1)

好的,我的答案代码没有组织,但是可以完成这项工作:

  

注意:当您使用"导出会话"时,请将渲染大小设置为以下代码: -

"[AVMixerBase shared].renderSize"

AVURLAsset*videoAsset = [[AVURLAsset alloc]initWithURL:url options:nil];
AVAssetTrack*videoAssetTrack = [[videoAsset tracksWithMediaType:AVMediaTypeVideo] firstObject];
[[AVMixerBase shared]setVideoAsset:videoAsset];

AVMutableComposition *mixComposition = [AVMixerBase compositionVideoTrackAssetUrl:videoAsset]; /* audio + video */
AVMutableCompositionTrack *compositionVideoTrack = [[mixComposition tracksWithMediaType:AVMediaTypeVideo] firstObject];
AVMutableVideoComposition *videoComposition = [AVMutableVideoComposition videoComposition];
AVMutableVideoCompositionLayerInstruction *layerInstruction = [AVMutableVideoCompositionLayerInstruction videoCompositionLayerInstructionWithAssetTrack:compositionVideoTrack];

CALayer *videoLayer = [self videoLayerAssetUrl:videoAsset];
CALayer *parentLayer = [CALayer layer];
CGSize videoSize = [videoAssetTrack naturalSize];
_segments = file.prefferedTranslation.customSegments;
NSLog(@"_segments %@",_segments);


//set render sizes:
//3.0_______COMBINE ALL
UIImageOrientation orientation = [self videoOrientation:videoAsset];
switch (orientation) {
    case UIImageOrientationUp:{ NSLog(@"Up"); //camera - lansdscape right
        [AVMixerBase shared].renderSize = CGSizeMake(videoSize.width, videoSize.height);
        break;
    }
    case UIImageOrientationDown:{ NSLog(@"Down"); //camera = lansdscape left
        [AVMixerBase shared].renderSize = CGSizeMake(videoSize.width, videoSize.height);
        videoLayer.affineTransform = CGAffineTransformMakeRotation(M_PI);
        break;
    }
    case UIImageOrientationLeft:{ NSLog(@"Left");

        break;
    }
    case UIImageOrientationRight:{ NSLog(@"Right");
        //camera = up
        CGAffineTransform t1 = CGAffineTransformMakeTranslation(videoSize.height, 0);
        CGAffineTransform t2 = CGAffineTransformRotate(t1, DEGREES_TO_RADIANS(90.0));
        [layerInstruction setTransform:t2 atTime:kCMTimeZero];
        [AVMixerBase shared].renderSize = CGSizeMake(videoSize.height, videoSize.width);
        break;
    }

    default:
        break;
}


  +(AVMutableComposition *)compositionVideoTrackAssetUrl:(AVURLAsset*)assetUrl{
AVMutableComposition* mixComposition = [AVMutableComposition composition];
mixComposition = [AVMixerBase addVideoTrackAssetUrl:assetUrl mixComposition:mixComposition];
return mixComposition;
}


   +(AVMutableComposition *)addVideoTrackAssetUrl:(AVURLAsset*)assetUrl mixComposition:(AVMutableComposition*)mixComposition{

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

AVAssetTrack *clipVideoTrack = [[assetUrl tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0];
AVAssetTrack *clipAudioTrack = [[assetUrl tracksWithMediaType:AVMediaTypeAudio] objectAtIndex:0];
[compositionVideoTrack insertTimeRange:CMTimeRangeMake(kCMTimeZero, assetUrl.duration) ofTrack:clipVideoTrack atTime:kCMTimeZero error:nil];
[compositionAudioTrack insertTimeRange:CMTimeRangeMake(kCMTimeZero, assetUrl.duration) ofTrack:clipAudioTrack atTime:kCMTimeZero error:nil];
[compositionVideoTrack setPreferredTransform:[[[assetUrl tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0] preferredTransform]];

return mixComposition;
}


-(CALayer*)videoLayerAssetUrl:(AVURLAsset*)assetUrl{
CGSize sizeOfVideo = [[[assetUrl tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0] naturalSize];
CALayer *videoLayer = [CALayer layer];
videoLayer.frame = CGRectMake(0, 0, sizeOfVideo.width, sizeOfVideo.height);
//    videoLayer.frame = CGRectMake(0, 0, sizeOfVideo.height, sizeOfVideo.width);
//    [videoLayer setAffineTransform:assetUrl.preferredTransform];


return videoLayer;
}