Bdtjtk

I want to save AVAssetWriter output to the camera roll, I'm currently saving it to the documents directory.

I have tried to use the UISaveVideoAtPathToSavedPhotosAlbum(_:_:_:_:) . I am currently using AVAssetWriter to write to the .documentsdirectotry. However, when I try to write, it fails silently. To write, I'll call startRecording() and I'll call stopRecording() to finish writing.

let captureSession = AVCaptureSession()

var videoOutput = AVCaptureVideoDataOutput()

var assetWriter: AVAssetWriter!

var assetWriterInput: AVAssetWriterInput!

var isCameraSetup = false

var hasStartedWritingCurrentVideo  = false

var isWriting = false

let queue = DispatchQueue(label: "com.name.camera-queue") 





// Camera preview setup code



//Setting up Asset Writer to save videos

public func setUpAssetWriter() {

    do {

        let documentsPath = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true).first

        let outputURL = URL(fileURLWithPath: documentsPath!).appendingPathComponent("test.m4v")

        assetWriter = try! AVAssetWriter(outputURL: outputURL, fileType: .mp4)

        assetWriterInput = AVAssetWriterInput(mediaType: .video, outputSettings: videoOutput.recommendedVideoSettingsForAssetWriter(writingTo: .mp4))

        assetWriterInput.expectsMediaDataInRealTime = true



        if assetWriter.canAdd(assetWriterInput) {

            assetWriter.add(assetWriterInput)

        } else {

            print("no input added")

        }

        assetWriter.startWriting()

        } catch let error {

        debugPrint(error.localizedDescription)

    }

}

public func tearDownAssetWriter() {

    assetWriter = nil

    assetWriterInput = nil

}

public func startWriting(){

    if isWriting{ return }

        setUpAssetWriter()

        hasStartedWritingCurrentVideo = false

        isWriting = true

}

public func finishWriting(_ completion: @escaping (URL) -> Void) {

    if isWriting == false { return }

    isWriting = false

    assetWriterInput.markAsFinished()

    let url = self.assetWriter.outputURL

    assetWriter.finishWriting {

        completion(url)

        self.tearDownAssetWriter()

    }

    hasStartedWritingCurrentVideo = false

}



// MARK: Starts the capture session

public func start() {

    if !captureSession.isRunning {

        captureSession.startRunning()

    }

}



public func stop() {

    if captureSession.isRunning {

        captureSession.stopRunning()

    }

}

// MARK: Records after camera is set up

public func startRecording() {

    startWriting()

    isWriting = true

}



public func stopRecording() {

    assetWriterInput.markAsFinished()

    assetWriter.finishWriting {

        [weak self] in return

    }

}

}



extension VideoCapture: AVCaptureVideoDataOutputSampleBufferDelegate {

    public func captureOutput(_ output: AVCaptureOutput, didOutput sampleBuffer: CMSampleBuffer, from connection: AVCaptureConnection) {

        // Because lowering the capture device's FPS looks ugly in the preview,

        // we capture at full speed but only call the delegate at its desired

        // framerate.

        let timestamp = CMSampleBufferGetPresentationTimeStamp(sampleBuffer)

        let deltaTime = timestamp - lastTimestamp

        if deltaTime >= CMTimeMake(value: 1, timescale: Int32(fps)) {

            lastTimestamp = timestamp

            let imageBuffer = CMSampleBufferGetImageBuffer(sampleBuffer)

            delegate?.videoCapture(self, didCaptureVideoFrame: imageBuffer, timestamp: timestamp)

        }

    // Asset Writer

        guard let assetWriter = assetWriter, let assetWriterInput = assetWriterInput else { return }

        if isWriting == false{ return }

        if self.assetWriter.status == .failed {

            setUpAssetWriter()

            hasStartedWritingCurrentVideo = false

        }

        if hasStartedWritingCurrentVideo == false && output === videoOutput { return }

        if hasStartedWritingCurrentVideo == false {

            hasStartedWritingCurrentVideo = true

            let sourceTime = CMSampleBufferGetPresentationTimeStamp(sampleBuffer)

            assetWriter.startSession(atSourceTime: sourceTime)

        }

        if output === videoOutput && assetWriterInput.isReadyForMoreMediaData{

            if isWriting == false{return}

            assetWriterInput.append(sampleBuffer)

        }

    }

}

The current implementation sets up the camera and preview, but then nothing is saved to the output.
It should save to the .documentDirectory, however, it's not saving. I would like to instead get it to save to the camera roll, but I'm not sure where exactly I should call UISaveVideoAtPathToSavedPhotosAlbum(_:_:_:_:).
The problem is likely in my extension delegate.

Thank you in advance for your help.

I am not familiar with UISaveVideoAtPathToSavedPhotosAlbum. But browsing stack overflow and git, many people use PHPhotoLibrary and so do I. Regardless of url, code below adds the video to photoLibrary.

https://developer.apple.com/documentation/photokit/phassetchangerequest/1624057-creationrequestforassetfromvideo

1) Info.plist
Add new key-value pair by + button. Select "Privary - Photo Library Usage Description" as a key. Set value something like "save video in photo library"

2) code

fileWriter.finishWriting(completionHandler: {

    let status = PHPhotoLibrary.authorizationStatus()



    //no access granted yet

    if status == .notDetermined || status == .denied{

        PHPhotoLibrary.requestAuthorization({auth in

            if auth == .authorized{

                saveInPhotoLibrary(url)

            }else{

                print("user denied access to photo Library")

            }

        })



    //access granted by user already

    }else{

        saveInPhotoLibrary(url)

    }

})



private func saveInPhotoLibrary(_ url:URL){

    PHPhotoLibrary.shared().performChanges({



        //add video to PhotoLibrary here

        PHAssetChangeRequest.creationRequestForAssetFromVideo(atFileURL: url)

    }) { completed, error in

        if completed {

            print("save complete! path : " + url.absoluteString)

        }else{

            print("save failed")

        }

    }

}

Hope this helps.
GW