RPScreenRecorder.shared().startCapture不会写/总是失败

Question

当尝试用ReplayKit记录和保存音频/视频时，我总是会出错。我在用

Xcode: Version 11.2.1
Swift 5
iOS 13
iPhone 7+ physical device

设置filePath时，我已经在使用网址(fileURLWithPath：)了。文件扩展名和AVFileType都是.mp4。我检查文件是否已经存在于FileManager中，如果已经存在，则删除它：do { try FileManager.default.removeItem(at: videoURL) }。我试图将路径本身更改为"Library/Caches/“，就像在@florianSAP答复中那样，这是不起作用的。

这里有三个错误：

// 1. from recording
if !self.assetWriter.startWriting() {
    print("Can't write")
    return
}

// 2. from recording
if self.assetWriter.status == AVAssetWriter.Status.failed {
    print("StartCapture Error Occurred, Status = \(self.assetWriter.status.rawValue), \(self.assetWriter.error?.localizedDescription) \(self.assetWriter.error?.debugDescription)")
    return
}

// 3. this one is when trying to save the url in the PHAssetChangeRequest.creationRequestForAssetFromVideo completionHandler
if let error = error {
    print("PHAssetChangeRequest Video Error: \(error.localizedDescription)")
    return
}

// 4. this isn't an error but inside the switch rpSampleBufferType { } statement "not a video sample" kept printing out

错误消息是：

StartCapture错误发生，状态= 3，操作无法完成可选(错误Domain=AVFoundationErrorDomain代码=-11800“操作无法完成”UserInfo={NSLocalizedFailureReason=An未知错误发生(-17508)，NSLocalizedDescription=The操作无法完成，NSUnderlyingError=0x2833a93b0 {错误Domain=NSOSStatusErrorDomain代码=-17508“(Null)}”} PHAssetChangeRequest视频错误:操作无法完成。(PHPhotosErrorDomain错误-1.)

，我在哪里做错了？

开始录音

let recorder = RPScreenRecorder.shared()
var assetWriter: AVAssetWriter!
var videoURL: URL!
var videoInput: AVAssetWriterInput!
var audioMicInput: AVAssetWriterInput!

guard let documentsPath = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true).first else { return }

videoURL = URL(fileURLWithPath: documentsPath.appending(UUID().uuidString + ".mp4"))

guard let videoURL = videoURL else { return }

do {
    try FileManager.default.removeItem(at: videoURL)
} catch {}

do {
    try assetWriter = AVAssetWriter(outputURL: videoURL, fileType: .mp4) // AVAssetWriter(url: videoURL, fileType: .mp4) didn't make a difference
} catch {}

let videoSettings: [String : Any] = [
    AVVideoCodecKey: AVVideoCodecType.h264,
    AVVideoWidthKey: view.bounds.width,
    AVVideoHeightKey: view.bounds.height
]

videoInput = AVAssetWriterInput(mediaType: .video, outputSettings: videoSettings)
videoInput.expectsMediaDataInRealTime = true
if assetWriter.canAdd(videoInput) {
    assetWriter.add(videoInput)
}

let audioSettings: [String:Any] = [AVFormatIDKey : kAudioFormatMPEG4AAC,
    AVNumberOfChannelsKey : 2,
    AVSampleRateKey : 44100.0,
    AVEncoderBitRateKey: 192000
]

audioMicInput = AVAssetWriterInput(mediaType: .audio, outputSettings: audioSettings)
audioMicInput.expectsMediaDataInRealTime = true
if assetWriter.canAdd(audioMicInput) {
    assetWriter.add(audioMicInput)
}

guard recorder.isAvailable else { return }

recorder.startCapture(handler: { (cmSampleBuffer, rpSampleBufferType, err) in

    if let err = err { return }

    // I tried to check if this was ready and added the below code to it but it made no difference
    // if CMSampleBufferDataIsReady(cmSampleBuffer) { ... the code below was put in here ... }

    DispatchQueue.main.async {

        switch rpSampleBufferType {
           case .video:

                if self.assetWriter.status == AVAssetWriter.Status.unknown {

                    if !self.assetWriter.startWriting() {
                        print("Can't write")
                        return
                    }

                    print("Starting writing")
                    self.assetWriter.startWriting()
                    self.assetWriter.startSession(atSourceTime:  CMSampleBufferGetPresentationTimeStamp(cmSampleBuffer))
                }

                if self.assetWriter.status == AVAssetWriter.Status.failed {
                    print("StartCapture Error Occurred, Status = \(self.assetWriter.status.rawValue), \(self.assetWriter.error?.localizedDescription) \(self.assetWriter.error?.debugDescription)")
                    return
                }

                if self.assetWriter.status == AVAssetWriter.Status.writing {
                    if self.videoInput.isReadyForMoreMediaData {
                        if self.videoInput.append(cmSampleBuffer) == false {
                            print("problem writing video")
                        }
                    }
                }

            case .audioMic:
                if self.audioMicInput.isReadyForMoreMediaData {
                    print("audioMic data added")
                    self.audioMicInput.append(cmSampleBuffer)
                }

            default:
                print("not a video sample")
            }
        }
    }

}, completionHandler: { (error) in

    if let error = error { return }
})

停止录音：

recorder.stopCapture { (error) in

    if let error = error { return }

    guard let videoInput = self.videoInput else { return }
    guard let audioMicInput = self.audioMicInput else { return }
    guard let assetWriter = self.assetWriter else { return }
    guard let videoURL = videoURL else { return }

    videoInput.markAsFinished()
    audioMicInput.markAsFinished()
    assetWriter.finishWriting(completionHandler: {

        PHPhotoLibrary.shared().performChanges({
                PHAssetChangeRequest.creationRequestForAssetFromVideo(atFileURL: videoUrl)
            }) { (saved, error) in

                if let error = error {
                    print("PHAssetChangeRequest Video Error: \(error.localizedDescription)")
                    return
                }

                if saved {
                    // ... show success message
                }
            }
    })
}

从未被调用的RPScreenRecorder代表：

func screenRecorder(_ screenRecorder: RPScreenRecorder, didStopRecordingWith previewViewController: RPPreviewViewController?, error: Error?) {
    if let error = error {
        print(error.localizedDescription)
    }
}

Answer 1

我可以通过做两件事来解决这个问题：

我做的第一件事是把videoURL的filePath从：

// Old Way that was causing some sort of path error
videoURL = URL(fileURLWithPath: documentsPath.appending(UUID().uuidString + ".mp4"))

// This is what the Old Path looked like. Look at the series of numbers beginning with 506... directly after Documents
///var/mobile/Containers/Data/Application/AAEF38A2-7AF1-4A32-A612-296B1584A764/Documents506D36BA-0C27-466A-A0BA-C197481F471A.mp4

至

// New Way that got the path to work
let dirPath = "\(documentsPath)/Videos_\(UUID().uuidString).mp4"
videoURL = URL(fileURLWithPath: dirPath)

// This is what the new path looks like. After Documents there is now a forward slash, the word Videos with an underscore, and then the series of numbers beginning with 506...
///var/mobile/Containers/Data/Application/AAEF38A2-7AF1-4A32-A612-296B1584A764/Documents/Videos_506D36BA-0C27-466A-A0BA-C197481F471A.mp4

2 -The我做的第二件事是更改recorder.startCapture(handler: { (cmSampleBuffer, rpSampleBufferType, err)中的代码

recorder.startCapture(handler: { (cmSampleBuffer, rpSampleBufferType, err) in

    if let err = err { return }

    if CMSampleBufferDataIsReady(cmSampleBuffer) {

        DispatchQueue.main.async {

            switch rpSampleBufferType {
            case .video:

                print("writing sample....")

                if self.assetWriter?.status == AVAssetWriter.Status.unknown {

                    print("Started writing")
                    self.assetWriter?.startWriting()
                    self.assetWriter?.startSession(atSourceTime: CMSampleBufferGetPresentationTimeStamp(cmSampleBuffer))
                }

                if self.assetWriter.status == AVAssetWriter.Status.failed {
                    print("StartCapture Error Occurred, Status = \(self.assetWriter.status.rawValue), \(self.assetWriter.error!.localizedDescription) \(self.assetWriter.error.debugDescription)")
                     return
                }

                if self.assetWriter.status == AVAssetWriter.Status.writing {
                    if self.videoInput.isReadyForMoreMediaData {
                        print("Writing a sample")
                        if self.videoInput.append(cmSampleBuffer) == false {
                             print("problem writing video")
                        }
                     }
                 }

            case .audioMic:
                if self.audioMicInput.isReadyForMoreMediaData {
                    print("audioMic data added")
                    self.audioMicInput.append(cmSampleBuffer)
                }

            default:
                print("not a video sample")
            }
        }
}, completionHandler: { (error) in

    if let error = error { return }
})

这与我遇到的实际问题无关，但是如果音频不是同步的，那么您必须将下面的代码添加到viewDidLoad中。我从评论部分在这里那里得到的。

do {
    try AVAudioSession.sharedInstance().setCategory(.playAndRecord, mode: .videoRecording, options: [.defaultToSpeaker])
    try AVAudioSession.sharedInstance().setActive(true, options: .notifyOthersOnDeactivation)
} catch {
    #if DEBUG
    print("Setting category to AVAudioSessionCategoryPlayback failed.")
    #endif
}

如果您需要找到错误代码的含义，您可以在这里查找https://www.osstatus.com。它帮助我找到了解决这个问题的11800，但没有找到17508。