问题与视频

Question

我想在视频中添加图像添加水印。一切工作正常，除了一两件事，图像变形：

下面是代码：

//Capture the image 
UIGraphicsBeginImageContextWithOptions(self.captureView.bounds.size, false, UIScreen.main.scale) 
self.captureView.layer.render(in: UIGraphicsGetCurrentContext()!) 
let image = UIGraphicsGetImageFromCurrentImageContext() 
UIGraphicsEndImageContext() 

let watermarkVideo = WatermakVideo() 

//video file 
let videoFile = Bundle.main.path(forResource: "videoTrim", ofType: "mp4") 
let videoURL = URL(fileURLWithPath: videoFile!) 

let imageFrame = captureView.frame 
watermarkVideo.createWatermark(image, frame: imageFrame, video: videoURL) 

这里是类WatermakVideo： https://www.dropbox.com/s/0d6i7ap9qu4klp5/WatermakVideo.zip

我是，如果感激你可以帮我解决这个问题。

Answer 1

复制以下到您的文件。我有同样的问题，两周前解决了这个问题：

-(void)forStackOverflow:(NSURL*)url{ 
AVURLAsset* videoAsset = [[AVURLAsset alloc]initWithURL:url options:nil]; 
    AVMutableComposition* mixComposition = [AVMutableComposition composition]; 

    AVMutableCompositionTrack *compositionVideoTrack = [mixComposition addMutableTrackWithMediaType:AVMediaTypeVideo preferredTrackID:kCMPersistentTrackID_Invalid]; 
    AVAssetTrack *clipVideoTrack = [[videoAsset tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0]; 
    AVMutableCompositionTrack *compositionAudioTrack = [mixComposition addMutableTrackWithMediaType:AVMediaTypeAudio preferredTrackID:kCMPersistentTrackID_Invalid]; 
    AVAssetTrack *clipAudioTrack = [[videoAsset tracksWithMediaType:AVMediaTypeAudio] objectAtIndex:0]; 
    //If you need audio as well add the Asset Track for audio here 

    [compositionVideoTrack insertTimeRange:CMTimeRangeMake(kCMTimeZero, videoAsset.duration) ofTrack:clipVideoTrack atTime:kCMTimeZero error:nil]; 
    [compositionAudioTrack insertTimeRange:CMTimeRangeMake(kCMTimeZero, videoAsset.duration) ofTrack:clipAudioTrack atTime:kCMTimeZero error:nil]; 

    [compositionVideoTrack setPreferredTransform:[[[videoAsset tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0] preferredTransform]]; 



    CGSize sizeOfVideo=compositionVideoTrack.naturalSize; 

    CGFloat scaleWidth = sizeOfVideo.height/self.view.frame.size.width; 
    CGFloat scaleHeight = sizeOfVideo.width/self.view.frame.size.height; 

    // add image 
    UIImage *myImage=[UIImage imageNamed:@"YOUR IMAGE PATH"]; 
    CALayer *layerCa = [CALayer layer]; 
    layerCa.contents = (id)myImage.CGImage; 
    layerCa.frame = CGRectMake(5*scaleWidth, 0, self.birdSize.width*scaleWidth, self.birdSize.height*scaleWidth); 
    layerCa.opacity = 1.0; 

    // add Text on image 
    CATextLayer *textOfvideo=[[CATextLayer alloc] init]; 
    textOfvideo.alignmentMode = kCAAlignmentLeft; 
    [textOfvideo setFont:(__bridge CFTypeRef)([UIFont fontWithName:@"Arial" size:64.00])];//fontUsed is the name of font 
    [textOfvideo setFrame:CGRectMake(layerCa.frame.size.width/6, layerCa.frame.size.height/8*7-layerCa.frame.size.height/3, layerCa.frame.size.width/1.5, layerCa.frame.size.height/3)]; 
    [textOfvideo setAlignmentMode:kCAAlignmentCenter]; 
    [textOfvideo setForegroundColor:[[UIColor redColor] CGColor]]; 

    UILabel*label = [[UILabel alloc]init]; 
    [label setText:self.questionString]; 
    label.textAlignment = NSTextAlignmentCenter; 
    label.numberOfLines = 4; 
    label.adjustsFontSizeToFitWidth = YES; 
    [label setFont:[UIFont fontWithName:@"Arial" size:64.00]]; 
    //[label.layer setBackgroundColor:[[UIColor blackColor] CGColor]]; 
    [label.layer setFrame:CGRectMake(0, 0, textOfvideo.frame.size.width, textOfvideo.frame.size.height)]; 
    [textOfvideo addSublayer:label.layer]; 


    [layerCa addSublayer:textOfvideo]; 



    CALayer *parentLayer=[CALayer layer]; 
    CALayer *videoLayer=[CALayer layer]; 
    parentLayer.frame=CGRectMake(0, 0, sizeOfVideo.width, sizeOfVideo.height); 
    videoLayer.frame=CGRectMake(0, 0, sizeOfVideo.height,sizeOfVideo.width); 
    [parentLayer addSublayer:videoLayer]; 
    //[parentLayer addSublayer:optionalLayer]; 
    [parentLayer addSublayer:layerCa]; 

    [parentLayer setBackgroundColor:[UIColor blueColor].CGColor]; 



    AVMutableVideoComposition *videoComposition=[AVMutableVideoComposition videoComposition] ; 
    videoComposition.frameDuration=CMTimeMake(1, 30); 
    videoComposition.animationTool=[AVVideoCompositionCoreAnimationTool videoCompositionCoreAnimationToolWithPostProcessingAsVideoLayer:videoLayer inLayer:parentLayer]; 

    //AVMutableVideoCompositionInstruction *instruction = [AVMutableVideoCompositionInstruction videoCompositionInstruction]; 
    AVMutableVideoCompositionInstruction *instruction = [AVMutableVideoCompositionInstruction videoCompositionInstruction]; 
    instruction.timeRange = CMTimeRangeMake(kCMTimeZero, [mixComposition duration]); 
    AVAssetTrack *videoTrack = [[mixComposition tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0]; 
    AVMutableVideoCompositionLayerInstruction* layerInstruction = [AVMutableVideoCompositionLayerInstruction videoCompositionLayerInstructionWithAssetTrack:videoTrack]; 

    UIImageOrientation videoAssetOrientation_ = UIImageOrientationUp; 
    BOOL isVideoAssetPortrait_ = NO; 
    [layerInstruction setTransform:videoTrack.preferredTransform atTime:kCMTimeZero]; 


    CGSize naturalSize; 
    naturalSize = videoTrack.naturalSize; 


    float renderWidth, renderHeight; 
    renderWidth = naturalSize.width; 
    renderHeight = naturalSize.height; 
    videoComposition.renderSize = naturalSize = CGSizeMake(videoTrack.naturalSize.height, videoTrack.naturalSize.width); 


    instruction.layerInstructions = [NSArray arrayWithObject:layerInstruction]; 
    videoComposition.instructions = [NSArray arrayWithObject: instruction]; 

    NSString *documentsDirectory = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)objectAtIndex:0]; 
    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init]; 
    [dateFormatter setDateFormat:@"yyyy-MM-dd_HH-mm-ss"]; 
    NSString *destinationPath = [documentsDirectory stringByAppendingFormat:@"/utput_%@.mov", [dateFormatter stringFromDate:[NSDate date]]]; 

    AVAssetExportSession *exportSession = [[AVAssetExportSession alloc] initWithAsset:mixComposition presetName:AVAssetExportPresetHighestQuality]; 
    exportSession.videoComposition=videoComposition; 

    exportSession.outputURL = [NSURL fileURLWithPath:destinationPath]; 
    exportSession.outputFileType = AVFileTypeQuickTimeMovie; 
    [exportSession exportAsynchronouslyWithCompletionHandler:^{ 
     switch (exportSession.status) 
     { 
      case AVAssetExportSessionStatusCompleted: 
       NSLog(@"Export OK"); 
       if (UIVideoAtPathIsCompatibleWithSavedPhotosAlbum(destinationPath)) { 
        UISaveVideoAtPathToSavedPhotosAlbum(destinationPath, self, @selector(video:didFinishSavingWithError:contextInfo:), nil); 
       } 
       break; 
      case AVAssetExportSessionStatusFailed: 
       NSLog (@"AVAssetExportSessionStatusFailed: %@", exportSession.error); 
       break; 
      case AVAssetExportSessionStatusCancelled: 
       NSLog(@"Export Cancelled"); 
       break; 
     } 
     self.currentUrl = exportSession.outputURL; 
     dispatch_async(dispatch_get_main_queue(), ^{ 

     }); 


    }]; 
}