以下代码完美地使用AVVideoCompositionCoreAnimationTool为视频添加徽标和文本。然后Swift 3来了!现在,有时视频会显示徽标和文字,有时视频会在导出时显示。
let videoComposition: AVMutableVideoComposition = AVMutableVideoComposition()
videoComposition.frameDuration = CMTimeMake(1, 60)
videoComposition.renderSize = CGSize(width: clipVideoTrack.naturalSize.height, height: clipVideoTrack.naturalSize.height)
let instruction: AVMutableVideoCompositionInstruction = AVMutableVideoCompositionInstruction()
instruction.timeRange = CMTimeRangeMake(kCMTimeZero, CMTimeMakeWithSeconds(60, 30))
// transformer is applied to set the video in portrait otherwise it is rotated by 90 degrees
let transformer: AVMutableVideoCompositionLayerInstruction =
AVMutableVideoCompositionLayerInstruction(assetTrack: clipVideoTrack)
let t1: CGAffineTransform = CGAffineTransform(translationX: clipVideoTrack.naturalSize.height, y: -(clipVideoTrack.naturalSize.width - clipVideoTrack.naturalSize.height)/2)
let t2: CGAffineTransform = t1.rotated(by: CGFloat(M_PI_2))
var finalTransform: CGAffineTransform = t2
transformer.setTransform(finalTransform, at: kCMTimeZero)
instruction.layerInstructions = NSArray(object: transformer) as! [AVVideoCompositionLayerInstruction]
videoComposition.instructions = NSArray(object: instruction) as! [AVVideoCompositionInstructionProtocol]
let mixComposition = AVMutableComposition()
let compositionVideoTrack = mixComposition.addMutableTrack(withMediaType: AVMediaTypeVideo, preferredTrackID: kCMPersistentTrackID_Invalid)
do {
try compositionVideoTrack.insertTimeRange(CMTimeRangeMake(kCMTimeZero, asset.duration), of: clipVideoTrack, at: kCMTimeZero)
} catch {
print(error)
}
//Add watermark
let myImage = UIImage(named: "logo")
let aLayer = CALayer()
aLayer.contents = myImage!.cgImage
aLayer.frame = CGRect(x: (clipVideoTrack.naturalSize.height*(self.view.bounds.width-45))/self.view.bounds.width, y: (clipVideoTrack.naturalSize.height*(self.view.bounds.width-40))/self.view.bounds.width, width: (clipVideoTrack.naturalSize.height*40)/self.view.bounds.width, height: (clipVideoTrack.naturalSize.height*40)/self.view.bounds.width)
let titleLayer = CATextLayer()
titleLayer.string = "text"
titleLayer.font = UIFont(name: "helvetica", size: 0)
titleLayer.fontSize = clipVideoTrack.naturalSize.height/16
titleLayer.shadowOpacity = 0.5
titleLayer.alignmentMode = kCAAlignmentCenter
titleLayer.frame = CGRect(x: 0, y: 0, width: clipVideoTrack.naturalSize.height, height: clipVideoTrack.naturalSize.height/6)
titleLayer.display()
let videoSize = asset.tracks(withMediaType: AVMediaTypeVideo)[0].naturalSize
let parentLayer = CALayer()
let videoLayer = CALayer()
parentLayer.frame = CGRect(x: 0, y: 0, width: videoSize.height, height: videoSize.height)
videoLayer.frame = CGRect(x: 0, y: 0, width: videoSize.height, height: videoSize.height)
parentLayer.addSublayer(videoLayer)
parentLayer.addSublayer(aLayer)
parentLayer.addSublayer(titleLayer)
videoComposition.animationTool = AVVideoCompositionCoreAnimationTool(postProcessingAsVideoLayer: videoLayer, in: parentLayer)
do { try FileManager.default.removeItem(at: filePath) }
catch let error as NSError {
NSLog("\(error), \(error.localizedDescription)")
}
var exportUrl: URL = filePath
self.videoUrl = filePath as NSURL
var exporter = AVAssetExportSession(asset: asset, presetName: AVAssetExportPresetMediumQuality)
exporter!.videoComposition = videoComposition
exporter!.outputFileType = AVFileTypeQuickTimeMovie
exporter!.outputURL = URL(fileURLWithPath: exportUrl.path)
exporter!.exportAsynchronously(completionHandler: {
DispatchQueue.main.async {
self.view.layer.addSublayer(self.avPlayerLayer)
let item = AVPlayerItem(url: exportUrl)
self.player.replaceCurrentItem(with: item)
if (self.player.currentItem != nil) {
print("Starting playback!")
self.player.play()
}
}
})
这与之前版本的Swift完美配合,但现在swift 3不再适用了。
请注意:如果我发表评论videoComposition.animationTool = AVVideoCompositionCoreAnimationTool(postProcessingAsVideoLayer: videoLayer, in: parentLayer)
,那么视频会被导出并成功播放,但没有任何叠加。
答案 0 :(得分:1)
看到代码适用于iOS 9,这可能是a bug in iOS 10.0 AVAssetExportSessions
videoComposition
设置@Rahul
时无法正常工作。
有些人报告iOS 10.1 beta内的情况看起来更好,其他人worked around the problem。