我的课程中有一个课程，它结合了大量的视频文件来制作1个整体视频。我有一个主要资产，我主要使用并在顶部应用其他资产。使用的唯一音频文件来自主资源。这是代码：
import UIKit
import AVFoundation
import Photos
class Merger: NSObject {
var controller:EditVideoViewController!
var button:AddAssetButton!
var view:UIView!
var difference:Double!
var changed:Bool = false
var AI:AIView!
convenience init(controller:EditVideoViewController, button:AddAssetButton) {
self.init()
self.controller = controller
self.button = button
self.view = UIView(frame: controller.view.bounds)
self.view.backgroundColor = UIColor.black.withAlphaComponent(0.7)
self.controller.view.addSubview(self.view)
}
func setupAI() {
self.AI = AIView(view: self.view)
self.AI.start()
}
func removeAI() {
self.AI.stop()
self.AI.removeEverything()
}
//The video is displaying in Portrait after merge.
func merge(completion:@escaping () -> Void, assets:[Asset]) {
self.setupAI()
let assets = assets.sorted(by: { $0.layer.zPosition < $1.layer.zPosition })
if let firstAsset = controller.firstAsset {
let mixComposition = AVMutableComposition()
let firstTrack = mixComposition.addMutableTrack(withMediaType: AVMediaTypeVideo,
preferredTrackID: Int32(kCMPersistentTrackID_Invalid))
do {
try firstTrack.insertTimeRange(CMTimeRangeMake(kCMTimeZero, self.controller.realDuration),
of: firstAsset.tracks(withMediaType: AVMediaTypeVideo)[0],
at: kCMTimeZero)
} catch _ {
print("Failed to load first track")
}
var myTracks:[AVMutableCompositionTrack] = []
for asset in assets {
let secondTrack = mixComposition.addMutableTrack(withMediaType: AVMediaTypeVideo,
preferredTrackID: Int32(kCMPersistentTrackID_Invalid))
secondTrack.preferredTransform = asset.asset.preferredTransform
do {
try secondTrack.insertTimeRange(CMTimeRangeMake(kCMTimeZero, asset.endTime-asset.beginTime),
of: asset.asset.tracks(withMediaType: AVMediaTypeVideo)[0],
at: CMTime(seconds: CMTimeGetSeconds(asset.beginTime), preferredTimescale: 600000))
} catch _ {
print("Failed to load second track")
}
myTracks.append(secondTrack)
}
if let loadedAudioAsset = controller.audioAsset {
let audioTrack = mixComposition.addMutableTrack(withMediaType: AVMediaTypeAudio, preferredTrackID: 0)
do {
try audioTrack.insertTimeRange(CMTimeRangeMake(kCMTimeZero, self.controller.realDuration),
of: loadedAudioAsset.tracks(withMediaType: AVMediaTypeAudio)[0] ,
at: kCMTimeZero)
} catch _ {
print("Failed to load Audio track")
}
}
let mainInstruction = AVMutableVideoCompositionInstruction()
mainInstruction.timeRange = CMTimeRangeMake(kCMTimeZero, self.controller.realDuration)
let firstInstruction = videoCompositionInstructionForTrack(firstTrack, firstAsset)
var instructions:[AVMutableVideoCompositionLayerInstruction] = []
var counter:Int = 0
for tracks in myTracks {
firstInstruction.setOpacity(0.0, at: assets[counter].beginTime)
let secondInstruction = videoCompositionInstructionForTrack(tracks, assets[counter].asset, type:true)
secondInstruction.setOpacity(0.0, at: assets[counter].endTime)
firstInstruction.setOpacity(1.0, at: assets[counter].endTime)
instructions.append(secondInstruction)
counter += 1
}
mainInstruction.layerInstructions = [firstInstruction] + instructions
let mainComposition = AVMutableVideoComposition()
mainComposition.instructions = [mainInstruction]
mainComposition.frameDuration = CMTimeMake(1, 30)
mainComposition.renderSize = self.controller.firstAsset!.tracks(withMediaType: AVMediaTypeVideo)[0].naturalSize
let documentDirectory = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0]
let savePath = (documentDirectory as NSString).appendingPathComponent("mergeVideo.mov")
let url = URL(fileURLWithPath: savePath)
_ = try? FileManager().removeItem(at: url)
guard let exporter = AVAssetExportSession(asset: mixComposition, presetName: AVAssetExportPresetHighestQuality) else { return }
exporter.outputFileType = AVFileTypeMPEG4
exporter.outputURL = url
exporter.videoComposition = mainComposition
exporter.exportAsynchronously(completionHandler: {
DispatchQueue.main.async(execute: {
self.exportDidFinish(exporter)
self.removeAI()
completion()
})
})
}
}
func exportDidFinish(_ exporter:AVAssetExportSession) {
if(exporter.status == AVAssetExportSessionStatus.completed) {
print("cool")
}
else if(exporter.status == AVAssetExportSessionStatus.failed) {
print(exporter.error as Any)
}
}
func videoCompositionInstructionForTrack(_ track: AVCompositionTrack, _ asset: AVAsset, type:Bool = false) -> AVMutableVideoCompositionLayerInstruction {
let instruction = AVMutableVideoCompositionLayerInstruction(assetTrack: track)
let assetTrack = asset.tracks(withMediaType: AVMediaTypeVideo)[0]
var transform = assetTrack.preferredTransform
let assetInfo = orientationFromTransform(transform)
let width = self.controller.firstAsset!.tracks(withMediaType: AVMediaTypeVideo)[0].naturalSize.width/assetTrack.naturalSize.width
var height = self.controller.firstAsset!.tracks(withMediaType: AVMediaTypeVideo)[0].naturalSize.height/assetTrack.naturalSize.height
if assetInfo.isPortrait {
//Vert Video taken from camera -- vert video from lib
height = self.controller.firstAsset!.tracks(withMediaType: AVMediaTypeVideo)[0].naturalSize.height/assetTrack.naturalSize.width
transform = transform.scaledBy(x: height, y: height)
let movement = ((1/height)*assetTrack.naturalSize.height)-assetTrack.naturalSize.height
transform = transform.translatedBy(x: 0, y: movement)
let totalBlackDistance = self.controller.firstAsset!.tracks(withMediaType: AVMediaTypeVideo)[0].naturalSize.width-transform.tx
transform = transform.translatedBy(x: 0, y: -(totalBlackDistance/2)*(1/height))
} else {
//Main Video -- hor photo from camera -- hor video from camera -- hor photo frmo lib -- hor vid frmo lib -- vert photos lib - vert photos camera
transform = transform.scaledBy(x: width, y: height)
let scale:CGFloat = ((self.controller.firstAsset!.tracks(withMediaType: AVMediaTypeVideo)[0].naturalSize.height/assetTrack.naturalSize.height)*(assetTrack.naturalSize.width))/self.controller.firstAsset!.tracks(withMediaType: AVMediaTypeVideo)[0].naturalSize.width
transform = transform.scaledBy(x: scale, y: 1)
let movement = ((self.controller.firstAsset!.tracks(withMediaType: AVMediaTypeVideo)[0].naturalSize.width-((self.controller.firstAsset!.tracks(withMediaType: AVMediaTypeVideo)[0].naturalSize.height/assetTrack.naturalSize.height)*(assetTrack.naturalSize.width)))/2)*(1/(self.controller.firstAsset!.tracks(withMediaType: AVMediaTypeVideo)[0].naturalSize.height/assetTrack.naturalSize.height))
transform = transform.translatedBy(x: movement, y: 0)
}
instruction.setTransform(transform, at: kCMTimeZero)
return instruction
}
func orientationFromTransform(_ transform: CGAffineTransform) -> (orientation: UIImageOrientation, isPortrait: Bool) {
var assetOrientation = UIImageOrientation.up
var isPortrait = false
if transform.a == 0 && transform.b == 1.0 && transform.c == -1.0 && transform.d == 0 {
assetOrientation = .right
isPortrait = true
} else if transform.a == 0 && transform.b == -1.0 && transform.c == 1.0 && transform.d == 0 {
assetOrientation = .left
isPortrait = true
} else if transform.a == 1.0 && transform.b == 0 && transform.c == 0 && transform.d == 1.0 {
assetOrientation = .up
} else if transform.a == -1.0 && transform.b == 0 && transform.c == 0 && transform.d == -1.0 {
assetOrientation = .down
}
return (assetOrientation, isPortrait)
}
}
对于我的手机，iPhone 6s，这永远不会崩溃，我从来没有遇到过问题。
我的一位拥有iPhone 5s的测试人员在导出过程中随机崩溃。当他的手机崩溃时，它似乎并没有像终止那样崩溃。应用程序完全关闭，没有任何反应。没有崩溃报告发送到我的管理器窗口（这经常发生）并且似乎没有任何问题。测试这个问题的另一个问题是他的app在不同的应用程序上做了。即使选择了相同的资产，它也不会每次都崩溃。如果我可以通过一些标准化定期复制这个问题，我就不会有这么多问题。但是，不确定从哪里开始。
这个测试仪不在我附近 - 我使用Apple的管理器窗口来获取崩溃报告
潜在解决方案
内存：我当时认为这可能是一个内存问题，因为我知道如果内存过载，那么它将终止应用程序。但是，没有任何内容发送到“DidReceiveMemoryWarning”，应用程序才会终止。
任何建议/解决方案？所有的帮助表示赞赏。
Xcode Organizer不会为您的应用提供每个崩溃报告，只有Apple知道他们如何选择他们提供的以及他们不提供的。通过TestFlight进行beta测试时，如果用户批准向开发人员提供崩溃报告数据，则报告有时可能需要几天时间才能到达。
即使应用程序因其他原因而被操作系统杀死，例如过多的内存消耗，崩溃报告将写入设备并提供给Apple，如果提供它的所有要求都是积极的，例如用户批准提供此数据。
没有报告就不可能说出发生了什么以及为什么，所以对内存使用问题的假设是一个疯狂的猜测，并且陈述的原因是无效的。
您需要获取崩溃报告并对其进行符号化。您的用户可以通过导航到“设置>常规>关于>诊断和使用数据”在设备上找到崩溃报告，然后复制内容并粘贴它，例如发送电子邮件并发送给您。