我想先修剪从photoLibrary中选择的视频，然后压缩视频文件以自定义大小和比特率。我使用PryntTrimmerView修剪视频，然后使用修剪过的视频压缩视频文件。 我的代码用于修剪和压缩视频文件。 我成功导出修剪资产，然后成功获取压缩文件。当我从图库中选择短视频时没有问题，但是当压缩后选择大尺寸视频时，控制台中出现此错误： 来自调试器的消息：由于内存问题而终止 有我用于修剪和压缩视频文件的代码。
func prepareAssetComposition() throws {
topActivity.isHidden = false
topActivity.startAnimating()
confirmButton.isUserInteractionEnabled = false
//get asset and track
guard let asset = trimmerView.asset, let videoTrack = asset.tracks(withMediaType: AVMediaTypeVideo).first else {
return
}
let assetComposition = AVMutableComposition()
let start = trimmerView.startTime?.seconds
let end = trimmerView.endTime?.seconds
let startTime = CMTime(seconds: Double(start ?? 0), preferredTimescale: 1000)
let endTime = CMTime(seconds: Double(end ?? 0), preferredTimescale: 1000)
let trackTimeRange = CMTimeRange(start: startTime, end: endTime)
let videoCompositionTrack = assetComposition.addMutableTrack(withMediaType: AVMediaTypeVideo, preferredTrackID: kCMPersistentTrackID_Invalid)
try videoCompositionTrack.insertTimeRange(trackTimeRange, of: videoTrack, at: kCMTimeZero)
if let audioTrack = asset.tracks(withMediaType: AVMediaTypeAudio).first {
let audioCompositionTrack = assetComposition.addMutableTrack(withMediaType: AVMediaTypeAudio, preferredTrackID: kCMPersistentTrackID_Invalid)
try audioCompositionTrack.insertTimeRange(trackTimeRange, of: audioTrack, at: kCMTimeZero)
}
//set video oriention to portrati
let size = videoTrack.naturalSize
let txf = videoTrack.preferredTransform
var recordType = ""
if (size.width == txf.tx && size.height == txf.ty){
recordType = "UIInterfaceOrientationLandscapeRight"
}else if (txf.tx == 0 && txf.ty == 0){
recordType = "UIInterfaceOrientationLandscapeLeft"
}else if (txf.tx == 0 && txf.ty == size.width){
recordType = "UIInterfaceOrientationPortraitUpsideDown"
}else{
recordType = "UIInterfaceOrientationPortrait"
}
if recordType == "UIInterfaceOrientationPortrait" {
let t1: CGAffineTransform = CGAffineTransform(translationX: videoTrack.naturalSize.height, y: -(videoTrack.naturalSize.width - videoTrack.naturalSize.height)/2)
let t2: CGAffineTransform = t1.rotated(by: CGFloat(Double.pi / 2))
let finalTransform: CGAffineTransform = t2
videoCompositionTrack.preferredTransform = finalTransform
}else if recordType == "UIInterfaceOrientationLandscapeRight" {
let t1: CGAffineTransform = CGAffineTransform(translationX: videoTrack.naturalSize.height, y: -(videoTrack.naturalSize.width - videoTrack.naturalSize.height)/2)
let t2: CGAffineTransform = t1.rotated(by: -CGFloat(Double.pi))
let finalTransform: CGAffineTransform = t2
videoCompositionTrack.preferredTransform = finalTransform
}else if recordType == "UIInterfaceOrientationPortraitUpsideDown" {
let t1: CGAffineTransform = CGAffineTransform(translationX: videoTrack.naturalSize.height, y: -(videoTrack.naturalSize.width - videoTrack.naturalSize.height)/2)
let t2: CGAffineTransform = t1.rotated(by: -CGFloat(Double.pi/2))
let finalTransform: CGAffineTransform = t2
videoCompositionTrack.preferredTransform = finalTransform
}
//start exporting video
var name = ""
var url: URL!
if self.state == .Left {
url = URL(fileURLWithPath: "\(NSTemporaryDirectory())TrimmedMovie1.mp4")
name = "TrimmedMovie1.mp4"
}else if state == .Right {
url = URL(fileURLWithPath: "\(NSTemporaryDirectory())TrimmedMovie3.mp4")
name = "TrimmedMovie3.mp4"
}else if state == .Center {
url = URL(fileURLWithPath: "\(NSTemporaryDirectory())TrimmedMovie2.mp4")
name = "TrimmedMovie2.mp4"
}
try? FileManager.default.removeItem(at: url)
let exportSession = AVAssetExportSession(asset: assetComposition, presetName: AVAssetExportPresetHighestQuality)
if UIDevice.current.userInterfaceIdiom == .phone {
exportSession?.outputFileType = AVFileTypeQuickTimeMovie
}else {
exportSession?.outputFileType = AVFileTypeQuickTimeMovie
}
exportSession?.shouldOptimizeForNetworkUse = true
exportSession?.outputURL = url
exportSession?.exportAsynchronously(completionHandler: {
DispatchQueue.main.async {
if let url = exportSession?.outputURL, exportSession?.status == .completed {
let asset = AVAsset(url: url)
print(asset.duration)
var thump: UIImage?
var vData: Data?
if let img = asset.videoThumbnail {
thump = img
if recordType == "UIInterfaceOrientationPortrait" {
if thump != nil {
let img = UIImage(cgImage: thump!.cgImage!, scale: CGFloat(1.0), orientation: .right)
thump = img
thump = thump?.fixedOrientation()
}
}else if recordType == "UIInterfaceOrientationLandscapeRight" {
if thump != nil {
let img = UIImage(cgImage: thump!.cgImage!, scale: CGFloat(1.0), orientation: .down)
thump = img
thump = thump?.fixedOrientation()
}
}else if recordType == "UIInterfaceOrientationPortraitUpsideDown" {
if thump != nil {
let img = UIImage(cgImage: thump!.cgImage!, scale: CGFloat(1.0), orientation: .left)
thump = img
thump = thump?.fixedOrientation()
}
}
}
if let videoData = NSData(contentsOf: url) {
vData = videoData as Data
}
if let delegate = self.delegate {
self.playbackTimeCheckerTimer?.invalidate()
self.playButton.setImage(#imageLiteral(resourceName: "play"), for: .normal)
self.playbackTimeCheckerTimer = nil
let size = CGSize(width: 1280, height: 720)
if let videoData = NSData(contentsOf: url) {
vData = videoData as Data
}
let directoryURL: URL = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)[0]
let folderPath: URL = directoryURL.appendingPathComponent(name, isDirectory: true)
do {
try vData?.write(to: folderPath, options: [])
}
catch {
print(error.localizedDescription)
}
self.compress(fileName:name,videoPath: folderPath.path, exportVideoPath: folderPath.path, renderSize: size, completion: {res in
if res {
OperationQueue.main.addOperation {
self.topActivity.isHidden = true
self.topActivity.stopAnimating()
self.confirmButton.isUserInteractionEnabled = true
delegate.setVideoFromPath(path: folderPath.path, thump: thump, videoData: vData)
self.dismiss(animated: true, completion: nil)
return
}
}else {
print("can not compress")
}
})
}
} else {
self.topActivity.isHidden = true
self.topActivity.stopAnimating()
self.confirmButton.isUserInteractionEnabled = true
let error = exportSession?.error
print("error exporting video \(String(describing: error))")
}
}
})
}
private func existsFileAtUrl(url:String,name:String) -> Bool {
let path = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0] as String
let url = URL(fileURLWithPath: path)
let filePath = url.appendingPathComponent(name).path
let fileManager = FileManager.default
if fileManager.fileExists(atPath: filePath) {
return true
} else {
return false
}
}
//MARK: Compress
func compress(fileName:String,videoPath : String, exportVideoPath : String, renderSize : CGSize, completion : @escaping (Bool) -> ()) {
let videoUrl = URL(fileURLWithPath: videoPath)
if (!existsFileAtUrl(url: videoUrl.absoluteString,name:fileName)) {
completion(false)
return
}
let videoAssetUrl = AVURLAsset(url: videoUrl)
let videoTrackArray = videoAssetUrl.tracks(withMediaType: AVMediaTypeVideo)
if videoTrackArray.count < 1 {
completion(false)
return
}
let videoAssetTrack = videoTrackArray[0]
let audioTrackArray = videoAssetUrl.tracks(withMediaType: AVMediaTypeAudio)
if audioTrackArray.count < 1 {
completion(false)
return
}
let audioAssetTrack = audioTrackArray[0]
let outputUrl = URL(fileURLWithPath: exportVideoPath)
var videoWriter = try? AVAssetWriter(url: outputUrl, fileType: AVFileTypeQuickTimeMovie)
videoWriter?.shouldOptimizeForNetworkUse = true
let vSetting = videoSettings(size: renderSize)
let videoWriterInput = AVAssetWriterInput(mediaType: AVMediaTypeVideo, outputSettings: vSetting)
videoWriterInput.expectsMediaDataInRealTime = false
videoWriterInput.transform = videoAssetTrack.preferredTransform
videoWriter?.add(videoWriterInput)
// output readers
let videoReaderSettings : [String : Int] = [kCVPixelBufferPixelFormatTypeKey as String : Int(kCVPixelFormatType_420YpCbCr8BiPlanarVideoRange)]
let videoReaderOutput = AVAssetReaderTrackOutput(track: videoAssetTrack, outputSettings: videoReaderSettings)
let videoReader = try! AVAssetReader(asset: videoAssetUrl)
videoReader.add(videoReaderOutput)
videoWriter?.startWriting()
videoReader.startReading()
videoWriter?.startSession(atSourceTime: kCMTimeZero)
let processingVideoQueue = DispatchQueue(label: "processingVideoCompressionQueue")
videoWriterInput.requestMediaDataWhenReady(on: processingVideoQueue, using: {
while(videoWriterInput.isReadyForMoreMediaData){
let sampleVideoBuffer = videoReaderOutput.copyNextSampleBuffer()
if (videoReader.status == .reading && sampleVideoBuffer != nil) {
videoWriterInput.append(sampleVideoBuffer!)
}else {
videoWriterInput.markAsFinished()
if (videoReader.status == .completed) {
videoWriter?.finishWriting(completionHandler: {
videoWriter = nil
completion(true)
})
}
}
}
})
}
//MARK: Setting
func videoSettings(size : CGSize) -> [String : AnyObject] {
var compressionSettings = [String : AnyObject]()
compressionSettings[AVVideoAverageBitRateKey] = 5 as AnyObject
var settings = [String : AnyObject]()
settings[AVVideoCompressionPropertiesKey] = compressionSettings as AnyObject
settings[AVVideoCodecKey] = AVVideoCodecH264 as AnyObject?
settings[AVVideoHeightKey] = size.height as AnyObject?
settings[AVVideoWidthKey] = size.width as AnyObject?
return settings
}
答案 0 :(得分：0)
我发现了问题，问题在于while语句。当我关闭视图控制器时，此语句反复调用，并且出现此错误。现在，当我想关闭视图控制器时，在带有break的循环中停止，一切正常。