Comment ajouter un filigrane de texte à la vidéo qui change chaque seconde dans Swift 3?

Question

J'ai créé un filigrane qui affiche l'heure actuelle, mais il ne change pas à chaque seconde. Comment ferais-je en sorte que le texte change chaque seconde? Je veux passer du temps sur des vidéos comme des images de sécurité. Voici un code qui fonctionne bien pour ajouter du texte sur une vidéo.

func waterMark(){ 
     let filePath: String = Bundle.main.path(forResource: "Zombie", ofType: "mp4")! 
     let videoAsset = AVURLAsset(url: URL(fileURLWithPath: filePath), options: nil) 
     let mixComposition = AVMutableComposition() 
     let compositionVideoTrack: AVMutableCompositionTrack? = mixComposition.addMutableTrack(withMediaType: AVMediaTypeVideo, preferredTrackID: kCMPersistentTrackID_Invalid) 

     let clipVideoTrack = videoAsset.tracks(withMediaType: AVMediaTypeVideo)[0] 
     try? compositionVideoTrack?.insertTimeRange(CMTimeRangeMake(kCMTimeZero, videoAsset.duration), of: clipVideoTrack, at: kCMTimeZero) 
     compositionVideoTrack?.preferredTransform = videoAsset.tracks(withMediaType: AVMediaTypeVideo)[0].preferredTransform 
     let videoSize: CGSize = clipVideoTrack.naturalSize 
     let aLayer = CALayer() 
     aLayer.contents = (Any).self 

     aLayer.frame = CGRect(x: videoSize.width - 65, y: videoSize.height - 75, width: 57, height: 57) 
     aLayer.opacity = 0.65 
     let parentLayer = CALayer() 
     let videoLayer = CALayer() 
     parentLayer.frame = CGRect(x: 0, y: 0, width: videoSize.width, height: videoSize.height) 
     videoLayer.frame = CGRect(x: 0, y: 0, width: videoSize.width, height: videoSize.height) 
     parentLayer.addSublayer(videoLayer) 
     parentLayer.addSublayer(aLayer) 
     let titleLayer = CATextLayer() 



     let dateFormatter = DateFormatter() 
    dateFormatter.timeStyle = .medium 

    // titleLayer.backgroundColor = UIColor.black.cgColor 
    titleLayer.string = String((dateFormatter.string(from: Date() as Date))) 

     titleLayer.font = UIFont.systemFont(ofSize: 100) 
     titleLayer.shadowOpacity = 0.5 
     titleLayer.frame = parentLayer.frame 
     titleLayer.display() 
     //You may need to adjust this for proper display 
     parentLayer.addSublayer(titleLayer as? CALayer ?? CALayer()) 
     let videoComp = AVMutableVideoComposition() 
     videoComp.renderSize = videoSize 
     videoComp.frameDuration = CMTimeMake(1, 30) 
     videoComp.animationTool = AVVideoCompositionCoreAnimationTool(postProcessingAsVideoLayer: videoLayer, in: parentLayer) 
     let instruction = AVMutableVideoCompositionInstruction() 
     instruction.timeRange = CMTimeRangeMake(kCMTimeZero, mixComposition.duration) 
     let videoTrack = mixComposition.tracks(withMediaType: AVMediaTypeVideo)[0] 
     let layerInstruction = AVMutableVideoCompositionLayerInstruction(assetTrack: videoTrack) 
     instruction.layerInstructions = [layerInstruction] 
     videoComp.instructions = [instruction] 
     let assetExport = AVAssetExportSession(asset: mixComposition, presetName: AVAssetExportPresetHighestQuality) 
     //AVAssetExportPresetPassthrough 
     assetExport?.videoComposition = videoComp 
     var paths: [Any] = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true) 

     let documentsDirectory: String = paths[0] as? String ?? "" 
     let VideoName: String = "\(documentsDirectory)/mynewwatermarkedvideo.mp4" 

     let exportUrl = URL(fileURLWithPath: VideoName) 
     if FileManager.default.fileExists(atPath: VideoName) { 
      print(VideoName) 
      try? FileManager.default.removeItem(atPath: VideoName) 
      print("file found again") 
     } 
     assetExport?.outputFileType = AVFileTypeQuickTimeMovie 
     assetExport?.outputURL = exportUrl 
     assetExport?.shouldOptimizeForNetworkUse = true 
     //[strRecordedFilename setString: exportPath]; 
     assetExport?.exportAsynchronously(completionHandler: {() -> Void in 
      DispatchQueue.main.async(execute: {() -> Void in 
      }) 
     }) 
     print("Completed") 

    } 



///call 
waterMark() 

Answer 1

Vous devez ajouter un temporisateur pour mettre à jour le calque de titre.

var timer: NSTimer? 

override func viewDidLoad() { 
    super.viewDidLoad() 

    timer = Timer.scheduledTimer(timeInterval: 60, target: self, selector: #selector(self.getTimeOfDate), userInfo: nil, repeats: true) 
} 

func getTimeOfDate() { 
    var curDate = Date() 

    timeLabel.text = formatter.string(from: curDate) 

}