VideoHDR.swift

        // HDR
    
        @IBOutlet weak var hdrButton: HDRButton!
    
        var currentHDRMode: HDRMode = .auto
    
        @IBAction func HDRButtonTouched(_ sender: HDRButton) {
            toggleHDR()
            sender.mode = currentHDRMode
        }
    
        func toggleHDR() {
            switch currentHDRMode {
            case .on:
                setHDR(.off)
            case .off:
                setHDR(.auto)
            case .auto:
                setHDR(.on)
            }
        }
    
        func setHDR(_ state: HDRMode) {
            guard camera.inputCamera.activeFormat.isVideoHDRSupported else {
                print("isVideoHDRSupported is false")
                return
            }
            do {
                try camera.inputCamera.lockForConfiguration()
                switch state {
                case .on:
                    camera.inputCamera.automaticallyAdjustsVideoHDREnabled = false
                    camera.inputCamera.isVideoHDREnabled = true
                case .off:
                    camera.inputCamera.automaticallyAdjustsVideoHDREnabled = false
                    camera.inputCamera.isVideoHDREnabled = false
                case .auto:
                    camera.inputCamera.automaticallyAdjustsVideoHDREnabled = true
                }
                camera.inputCamera.unlockForConfiguration()
            } catch {
                print("Could not lock configuration")
            }
        }