Swift 3：AVVideoCompositionを使用してテキストで動画を書き出す方法

Question

AVVideoCompositionを使用して動画の上にテキストを追加して動画を保存しようとしています。 これは私が使用するコードである：

IははAVMutableComposition and AVVideoComposition

var mutableComp =   AVMutableComposition() 
var mutableVidComp =  AVMutableVideoComposition() 
var compositionSize :  CGSize? 

func configureAsset(){ 

    let options =    [AVURLAssetPreferPreciseDurationAndTimingKey : "true"] 
    let videoAsset =    AVURLAsset(url: Bundle.main.url(forResource: "Car", withExtension: "mp4")! , options : options) 
    let videoAssetSourceTrack = videoAsset.tracks(withMediaType: AVMediaTypeVideo).first! as AVAssetTrack 

    compositionSize = videoAssetSourceTrack.naturalSize 

    let mutableVidTrack =  mutableComp.addMutableTrack(withMediaType: AVMediaTypeVideo, preferredTrackID: kCMPersistentTrackID_Invalid) 
    let trackRange =   CMTimeRangeMake(kCMTimeZero, videoAsset.duration) 

    do { 
     try mutableVidTrack.insertTimeRange(trackRange, of: videoAssetSourceTrack, at: kCMTimeZero) 

     mutableVidTrack.preferredTransform = videoAssetSourceTrack.preferredTransform 

    }catch { print(error) } 

    snapshot =  mutableComp 
    mutableVidComp = AVMutableVideoComposition(propertiesOf: videoAsset) 
} 

IIセットアップ層

func applyVideoEffectsToComposition() { 

    // 1 - Set up the text layer 
    let subTitle1Text =   CATextLayer() 
    subTitle1Text.font =   "Helvetica-Bold" as CFTypeRef 
    subTitle1Text.frame =   CGRect(x: self.view.frame.midX - 60 , y: self.view.frame.midY - 50, width: 120, height: 100) 
    subTitle1Text.string =   "Bench" 
    subTitle1Text.foregroundColor = UIColor.black.cgColor 
    subTitle1Text.alignmentMode = kCAAlignmentCenter 

    // 2 - The usual overlay 
    let overlayLayer = CALayer() 
    overlayLayer.addSublayer(subTitle1Text) 
    overlayLayer.frame = CGRect(x: 0, y: 0, width: compositionSize!.width, height: compositionSize!.height) 
    overlayLayer.masksToBounds = true 


    // 3 - set up the parent layer 
    let parentLayer = CALayer() 
    let videoLayer = CALayer() 
    parentLayer.frame = CGRect(x: 0, y: 0, width: compositionSize!.width, height: compositionSize!.height) 
    videoLayer.frame = CGRect(x: 0, y: 0, width: compositionSize!.width, height: compositionSize!.height) 

    parentLayer.addSublayer(videoLayer) 
    parentLayer.addSublayer(overlayLayer) 

    mutableVidComp.animationTool = AVVideoCompositionCoreAnimationTool(postProcessingAsVideoLayer: videoLayer, in: parentLayer) 

} 

IIIを作成します。その後、私は簡単なテストのためにviewDidLoad方法のすべての3つのメソッドを実行しAVMutbaleVideoComposition

func saveAsset(){ 

func deleteFile(_ filePath:URL) { 

guard FileManager.default.fileExists(atPath: filePath.path) else { return } 

do { 
try FileManager.default.removeItem(atPath: filePath.path) } 
catch {fatalError("Unable to delete file: \(error) : \(#function).")} } 


let documentsDirectory = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)[0] as URL 
let filePath =   documentsDirectory.appendingPathComponent("rendered-audio.mp4") 
deleteFile(filePath) 

if let exportSession = AVAssetExportSession(asset: mutableComp , presetName: AVAssetExportPresetHighestQuality){ 

    exportSession.videoComposition = mutableVidComp 

// exportSession.canPerformMultiplePassesOverSourceMediaData = true 
exportSession.outputURL =     filePath 
exportSession.shouldOptimizeForNetworkUse = true 
exportSession.timeRange =     CMTimeRangeMake(kCMTimeZero, mutableComp.duration) 
exportSession.outputFileType =    AVFileTypeQuickTimeMovie 



exportSession.exportAsynchronously { 
print("finished: \(filePath) : \(exportSession.status.rawValue) ") 

if exportSession.status.rawValue == 4 { 

print("Export failed -> Reason: \(exportSession.error!.localizedDescription))") 
print(exportSession.error!) }}}} 

で動画を保存します。問題は、私がアプリを実行すると、エクスポートの結果は、それにタイトルがない元のビデオです。私はここで何が欠けていますか？私はコードの 一部IIにsubTitle1Text.backgroundColorプロパティを追加することを確認

UPDATE

エクスポート場合subTitle1Text.frameに対応する着色CGRectがビデオの上に表示させます。 (See Image) AVSynchronizedLayerを使用して再生するためにこのコードを変更すると、テキストの上に目的のレイヤーが表示されます。 これはおそらくAVFoundationのバグです。

customVideoCompositorClassを使用するオプションが残っているとします。その問題は、ビデオのレンダリングに多くの時間がかかることです。ここでAVVideoCompositingを使用する例です： https://github.com/samsonjs/LayerVideoCompositor

Answer 1

ここで私は私のプロジェクトで使用される完全に動作するコードがあります。下部（0,0）にCATextLayerが表示されます。また、エクスポートセッションの終了時には、プレーヤーアイテムの新しいパスを置き換えます。私はObjective Cのコードから向きを取得するために1つのモデルを使用しました。デバイスでテストしてください。 AVPLayerはシミュレータにテキストレイヤーを正しく表示しません。以下は

let composition = AVMutableComposition.init() 

    let videoComposition = AVMutableVideoComposition() 
    videoComposition.frameDuration = CMTimeMake(1, 30) 
    videoComposition.renderScale = 1.0 

    let compositionCommentaryTrack: AVMutableCompositionTrack? = composition.addMutableTrack(withMediaType: AVMediaTypeAudio, preferredTrackID: kCMPersistentTrackID_Invalid) 


    let compositionVideoTrack: AVMutableCompositionTrack? = composition.addMutableTrack(withMediaType: AVMediaTypeVideo, preferredTrackID: kCMPersistentTrackID_Invalid) 


    let clipVideoTrack:AVAssetTrack = self.currentAsset.tracks(withMediaType: AVMediaTypeVideo)[0] 

    let audioTrack: AVAssetTrack? = self.currentAsset.tracks(withMediaType: AVMediaTypeAudio)[0] 

    try? compositionCommentaryTrack?.insertTimeRange(CMTimeRangeMake(kCMTimeZero, self.currentAsset.duration), of: audioTrack!, at: kCMTimeZero) 

    try? compositionVideoTrack?.insertTimeRange(CMTimeRangeMake(kCMTimeZero, self.currentAsset.duration), of: clipVideoTrack, at: kCMTimeZero) 

    let orientation = VideoModel.videoOrientation(self.currentAsset) 
    var isPortrait = false 

    switch orientation { 
    case .landscapeRight: 
     isPortrait = false 
    case .landscapeLeft: 
     isPortrait = false 
    case .portrait: 
     isPortrait = true 
    case .portraitUpsideDown: 
     isPortrait = true 
    } 

    var naturalSize = clipVideoTrack.naturalSize 

    if isPortrait 
    { 
     naturalSize = CGSize.init(width: naturalSize.height, height: naturalSize.width) 
    } 

    videoComposition.renderSize = naturalSize 

    let scale = CGFloat(1.0) 

    var transform = CGAffineTransform.init(scaleX: CGFloat(scale), y: CGFloat(scale)) 

    switch orientation { 
    case .landscapeRight: break 
    // isPortrait = false 
    case .landscapeLeft: 
     transform = transform.translatedBy(x: naturalSize.width, y: naturalSize.height) 
     transform = transform.rotated(by: .pi) 
    case .portrait: 
     transform = transform.translatedBy(x: naturalSize.width, y: 0) 
     transform = transform.rotated(by: CGFloat(M_PI_2)) 
    case .portraitUpsideDown:break 
    } 

    let frontLayerInstruction = AVMutableVideoCompositionLayerInstruction(assetTrack: compositionVideoTrack!) 
    frontLayerInstruction.setTransform(transform, at: kCMTimeZero) 

    let MainInstruction = AVMutableVideoCompositionInstruction() 
    MainInstruction.timeRange = CMTimeRangeMake(kCMTimeZero, composition.duration) 
    MainInstruction.layerInstructions = [frontLayerInstruction] 
    videoComposition.instructions = [MainInstruction] 

    let parentLayer = CALayer.init() 
    parentLayer.frame = CGRect.init(x: 0, y: 0, width: naturalSize.width, height: naturalSize.height) 

    let videoLayer = CALayer.init() 
    videoLayer.frame = parentLayer.frame 


    let layer = CATextLayer() 
    layer.string = "HELLO ALL" 
    layer.foregroundColor = UIColor.white.cgColor 
    layer.backgroundColor = UIColor.orange.cgColor 
    layer.fontSize = 32 
    layer.frame = CGRect.init(x: 0, y: 0, width: 300, height: 100) 

    var rct = layer.frame; 

    let widthScale = self.playerView.frame.size.width/naturalSize.width 

    rct.size.width /= widthScale 
    rct.size.height /= widthScale 
    rct.origin.x /= widthScale 
    rct.origin.y /= widthScale 



    parentLayer.addSublayer(videoLayer) 
    parentLayer.addSublayer(layer) 

    videoComposition.animationTool = AVVideoCompositionCoreAnimationTool.init(postProcessingAsVideoLayer: videoLayer, in: parentLayer) 

    let documentsPath = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0] 
    let videoPath = documentsPath+"/cropEditVideo.mov" 

    let fileManager = FileManager.default 

    if fileManager.fileExists(atPath: videoPath) 
    { 
     try! fileManager.removeItem(atPath: videoPath) 
    } 

    print("video path \(videoPath)") 

    var exportSession = AVAssetExportSession.init(asset: composition, presetName: AVAssetExportPresetHighestQuality) 
    exportSession?.videoComposition = videoComposition 
    exportSession?.outputFileType = AVFileTypeQuickTimeMovie 
    exportSession?.outputURL = URL.init(fileURLWithPath: videoPath) 
    exportSession?.videoComposition = videoComposition 
    var exportProgress: Float = 0 
    let queue = DispatchQueue(label: "Export Progress Queue") 
    queue.async(execute: {() -> Void in 
     while exportSession != nil { 
      //    int prevProgress = exportProgress; 
      exportProgress = (exportSession?.progress)! 
      print("current progress == \(exportProgress)") 
      sleep(1) 
     } 
    }) 

    exportSession?.exportAsynchronously(completionHandler: { 


     if exportSession?.status == AVAssetExportSessionStatus.failed 
     { 
      print("Failed \(exportSession?.error)") 
     }else if exportSession?.status == AVAssetExportSessionStatus.completed 
     { 
      exportSession = nil 

      let asset = AVAsset.init(url: URL.init(fileURLWithPath: videoPath)) 
      DispatchQueue.main.async { 
       let item = AVPlayerItem.init(asset: asset) 


       self.player.replaceCurrentItem(with: item) 

       let assetDuration = CMTimeGetSeconds(composition.duration) 
       self.progressSlider.maximumValue = Float(assetDuration) 

       self.syncLayer.removeFromSuperlayer() 
       self.lblIntro.isHidden = true 

       self.player.play() 
       //     let url = URL.init(fileURLWithPath: videoPath) 
       //     let activityVC = UIActivityViewController(activityItems: [url], applicationActivities: []) 
       //     self.present(activityVC, animated: true, completion: nil) 
      } 

     } 
    }) 

マイVideoModelクラスのコード

-(AVCaptureVideoOrientation)videoOrientation:(AVAsset *)asset 
{ 
    AVCaptureVideoOrientation result = 0; 
    NSArray *tracks = [asset tracksWithMediaType:AVMediaTypeVideo]; 
    if([tracks count] > 0) { 
     AVAssetTrack *videoTrack = [tracks objectAtIndex:0]; 
     CGAffineTransform t = videoTrack.preferredTransform; 
     // Portrait 
     if(t.a == 0 && t.b == 1.0 && t.c == -1.0 && t.d == 0) 
     { 
      result = AVCaptureVideoOrientationPortrait; 
     } 
     // PortraitUpsideDown 
     if(t.a == 0 && t.b == -1.0 && t.c == 1.0 && t.d == 0) { 

      result = AVCaptureVideoOrientationPortraitUpsideDown; 
     } 
     // LandscapeRight 
     if(t.a == 1.0 && t.b == 0 && t.c == 0 && t.d == 1.0) 
     { 
      result = AVCaptureVideoOrientationLandscapeRight; 
     } 
     // LandscapeLeft 
     if(t.a == -1.0 && t.b == 0 && t.c == 0 && t.d == -1.0) 
     { 
      result = AVCaptureVideoOrientationLandscapeLeft; 
     } 
    } 
    return result; 
} 

あなたがこの中に任意のより多くの助けが必要なら、私に知らせています。