CaptureViewController

CaptureViewController.swift

import UIKit
import AVFoundation

class CaptureViewController: UIViewController {
    var captureSession: AVCaptureSession?
    var captureVideoPreviewLayer: AVCaptureVideoPreviewLayer?

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
        
        guard let captureDevice = AVCaptureDevice.default(for: .video) else {
            return
        }
        
        guard let captureDeviceInput = try? AVCaptureDeviceInput(device: captureDevice) else {
            return
        }
        
        self.captureSession = AVCaptureSession()
        self.captureSession?.addInput(captureDeviceInput)
        
        guard let captureSession = self.captureSession else {
            return
        }
        
        self.captureVideoPreviewLayer = AVCaptureVideoPreviewLayer(session: captureSession)
        self.captureVideoPreviewLayer?.videoGravity = .resizeAspectFill
        self.captureVideoPreviewLayer?.frame        = view.layer.bounds
        
        guard let captureVideoPreviewLayer = self.captureVideoPreviewLayer else {
            return
        }
        
        self.view.layer.addSublayer(captureVideoPreviewLayer)
        self.captureSession?.startRunning()
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }
}