Swift 3 - How to capture image and its subview? - ios

Question

I am working on a project that contains custom camera view.And i am unable to capture the subview over the main view.My main view consist of AVCaptureSession and i want to take photo of superview and subview both in single image.
What i am trying in code:
class ViewController: UIViewController {
#IBOutlet weak var cameraButton: UIButton!
var captureSession = AVCaptureSession()
var backCamera: AVCaptureDevice?
var frontCamera: AVCaptureDevice?
var currentDevice: AVCaptureDevice?
var photoOutput: AVCapturePhotoOutput?
var cameraPreviewLayer:AVCaptureVideoPreviewLayer?
var image: UIImage?
var toggleCameraGestureRecognizer = UISwipeGestureRecognizer()
var zoomInGestureRecognizer = UISwipeGestureRecognizer()
var zoomOutGestureRecognizer = UISwipeGestureRecognizer()
override func viewDidLoad() {
super.viewDidLoad()
setupCaptureSession()
setupDevice()
setupInputOutput()
setupPreviewLayer()
captureSession.startRunning()
toggleCameraGestureRecognizer.direction = .up
toggleCameraGestureRecognizer.addTarget(self, action: #selector(self.switchCamera))
view.addGestureRecognizer(toggleCameraGestureRecognizer)
// Zoom In recognizer
zoomInGestureRecognizer.direction = .right
zoomInGestureRecognizer.addTarget(self, action: #selector(zoomIn))
view.addGestureRecognizer(zoomInGestureRecognizer)
// Zoom Out recognizer
zoomOutGestureRecognizer.direction = .left
zoomOutGestureRecognizer.addTarget(self, action: #selector(zoomOut))
view.addGestureRecognizer(zoomOutGestureRecognizer)
styleCaptureButton()
}
cameraButton.layer.borderColor = UIColor.white.cgColor
cameraButton.layer.borderWidth = 5
cameraButton.clipsToBounds = true
cameraButton.layer.cornerRadius = min(cameraButton.frame.width, cameraButton.frame.height) / 2
}
func setupCaptureSession() {
captureSession.sessionPreset = AVCaptureSession.Preset.photo
}
func setupDevice() {
let deviceDiscoverySession = AVCaptureDevice.DiscoverySession(deviceTypes: [AVCaptureDevice.DeviceType.builtInWideAngleCamera], mediaType: AVMediaType.video, position: AVCaptureDevice.Position.unspecified)
let devices = deviceDiscoverySession.devices
for device in devices {
if device.position == AVCaptureDevice.Position.back {
backCamera = device
} else if device.position == AVCaptureDevice.Position.front {
frontCamera = device
}
}
currentDevice = backCamera
}
func setupInputOutput() {
do {
let captureDeviceInput = try AVCaptureDeviceInput(device: currentDevice!)
captureSession.addInput(captureDeviceInput)
photoOutput = AVCapturePhotoOutput()
photoOutput!.setPreparedPhotoSettingsArray([AVCapturePhotoSettings(format: [AVVideoCodecKey : AVVideoCodecType.jpeg])], completionHandler: nil)
captureSession.addOutput(photoOutput!)
} catch {
print(error)
}
}
func setupPreviewLayer() {
self.cameraPreviewLayer = AVCaptureVideoPreviewLayer(session: captureSession)
self.cameraPreviewLayer?.videoGravity = AVLayerVideoGravity.resizeAspectFill
self.cameraPreviewLayer?.connection?.videoOrientation = AVCaptureVideoOrientation.portrait
self.cameraPreviewLayer?.frame = view.frame
self.view.layer.insertSublayer(self.cameraPreviewLayer!, at: 0)
}
#IBAction func cameraButton_TouchUpInside(_ sender: Any) {
let settings = AVCapturePhotoSettings()
self.photoOutput?.capturePhoto(with: settings, delegate: self)
}
}
extension ViewController: AVCapturePhotoCaptureDelegate {
func photoOutput(_ output: AVCapturePhotoOutput, didFinishProcessingPhoto photo: AVCapturePhoto, error: Error?) {
if let imageData = photo.fileDataRepresentation() {
self.image = UIImage(data: imageData)
performSegue(withIdentifier: "Preview_Segue", sender: nil)
}
}
}
Please help me

Answer 1

If I understood you are trying to get the content (as an image) of what the camera is grabbing and some overlay views.
As far as I remember is not possible to grab what is inside the AVPreviewLayer, maybe they changed something in the latest version. When I tried (iOS6) it wasn't possible, the area with the AVPreviewLayer was always empty.
What you can do is take the current camera buffer and draw inside it. By setting a class as a session delegate you can receive this callback optional
func captureOutput(_ output: AVCaptureOutput,
didOutput sampleBuffer: CMSampleBuffer,
from connection: AVCaptureConnection)
Here you will receive the image from the camera, this buffer can be converted into images using Accelerate framework or CoreImage.
Is not easy, but also not impossible.