define video url as the uiview in your class - swift

Question

My swift code should be able to take a snapshot of a video and then take that image and display in a uiimageview. Instead of using a online link I just want the url to be the uiview in my class.So the video url should be previewView not the https link that I have below. All the code below is in this class
import UIKit;import AVFoundation
class ViewController: UIViewController, AVCapturePhotoCaptureDelegate {
#IBOutlet var previewView : UIView!
#IBOutlet var captureImageView : UIImageView!
var captureSession: AVCaptureSession!
var stillImageOutput: AVCapturePhotoOutput!
var videoPreviewLayer: AVCaptureVideoPreviewLayer!
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
// Setup your camera here...
captureSession = AVCaptureSession()
captureSession.sessionPreset = .medium
guard let backCamera = AVCaptureDevice.default(for: AVMediaType.video)
else {
print("Unable to access back camera!")
return
}
do {
let input = try AVCaptureDeviceInput(device: backCamera)
//Step 9
stillImageOutput = AVCapturePhotoOutput()
stillImageOutput = AVCapturePhotoOutput()
if captureSession.canAddInput(input) && captureSession.canAddOutput(stillImageOutput) {
captureSession.addInput(input)
captureSession.addOutput(stillImageOutput)
setupLivePreview()
}
}
catch let error {
print("Error Unable to initialize back camera: \(error.localizedDescription)")
}
}
func setupLivePreview() {
videoPreviewLayer = AVCaptureVideoPreviewLayer(session: captureSession)
videoPreviewLayer.videoGravity = .resizeAspect
videoPreviewLayer.connection?.videoOrientation = .portrait
previewView.layer.addSublayer(videoPreviewLayer)
//Step12
DispatchQueue.global(qos: .userInitiated).async { //[weak self] in
self.captureSession.startRunning()
//Step 13
DispatchQueue.main.async {
self.videoPreviewLayer.frame = self.previewView.bounds
}
}
}
#IBAction func startRecord(_ sender: Any) {
}
#IBAction func Save(_ sender: Any) {
//what do I put in the 2 highlighted blocks
let videoURL = "https://www.youtube.com/watch?v=Txt25dw-lIk"
self.getThumbnailFromUrl(videoURL) { [weak self] (img) in
guard let _ = self else { return }
if let img = img {
self?.captureImageView.image = img
}
}
}
func getThumbnailFromUrl(_ url: String?, _ completion: #escaping ((_ image: UIImage?)->Void)) {
guard let url = URL(string: url ?? "") else { return }
DispatchQueue.main.async {
let asset = AVAsset(url: url)
let assetImgGenerate = AVAssetImageGenerator(asset: asset)
assetImgGenerate.appliesPreferredTrackTransform = true
let time = CMTimeMake(value: 2, timescale: 1)
do {
let img = try assetImgGenerate.copyCGImage(at: time, actualTime: nil)
let thumbnail = UIImage(cgImage: img)
completion(thumbnail)
} catch {
print("Error :: ", error.localizedDescription)
completion(nil)
}
}
}
#IBAction func didTakePhoto(_ sender: Any) {
let settings = AVCapturePhotoSettings(format: [AVVideoCodecKey: AVVideoCodecType.jpeg])
stillImageOutput.capturePhoto(with: settings, delegate: self)
}
func photoOutput(_ output: AVCapturePhotoOutput, didFinishProcessingPhoto photo: AVCapturePhoto, error: Error?) {
guard let imageData = photo.fileDataRepresentation()
else { return }
let image = UIImage(data: imageData)
captureImageView.image = image
}
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
self.captureSession.stopRunning()
}
}