title: Swift how to set Editor crop size for editor in UIImagepickercontroller
body: <p>For my iOS app I need a Fotoeditor. Therefore I set:</p>
  
  <pre><code>imagePicker.allowsEditing = true
  </code></pre>
  
  <p>Now I would like to change the size of the editable area.</p>
  
  <p>Here is the editable area, but I need the size of the usable image different:</p>
  
  <p><img src="https://i.stack.imgur.com/5LBbT.jpg" alt="image"></p>
  
  <p>How can I change the size of this area to use a different size for the usable image area?</p>
  
  <p>Here is my code for my PickerController</p>
  
  <pre><code>@IBOutlet weak var preview: UIImageView!
  
  let imagePicker = UIImagePickerController()
  
  @IBAction func selectImage(_ sender: Any) {
      imagePicker.allowsEditing = true
      imagePicker.sourceType = .photoLibrary
  
      present(imagePicker, animated: true, completion: nil)
  }
  
  override func viewDidLoad() {
      super.viewDidLoad()
  
      imagePicker.delegate = self
  }
  
  func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
      if let pickedImage = info[UIImagePickerControllerOriginalImage] as? UIImage{
          preview.contentMode = .scaleAspectFit
          preview.image = pickedImage
      }
      dismiss(animated: true, completion: nil)
  }
  
  func imagePickerControllerDidCancel(_ picker: UIImagePickerController) {
      dismiss(animated: true, completion: nil)
  }
  </code></pre>