【Xcode/Swift】画像をトリミングする方法

import UIKit
import CropViewController

class ViewController: UIViewController {
    
    @IBOutlet weak var imageView: UIImageView!
    
    override func viewDidLoad() {
        super.viewDidLoad()
    }
    
    //アルバムを開く
    private func setImagePicker(){
        let picker = UIImagePickerController()
        picker.sourceType = .photoLibrary
        picker.delegate = self
        present(picker, animated: true, completion: nil)
    }
    
    @IBAction func trimImageAction(_ sender: Any) {
        setImagePicker()
    }
    
}

extension ViewController: CropViewControllerDelegate {
    func cropViewController(_ cropViewController: CropViewController, didCropToImage image: UIImage, withRect cropRect: CGRect, angle: Int) {
        updateImageViewWithImage(image, fromCropViewController: cropViewController)
    }
    
    //加工画面を閉じて画像を表示する
    func updateImageViewWithImage(_ image: UIImage, fromCropViewController cropViewController: CropViewController) {
        imageView.image = image
        cropViewController.dismiss(animated: true, completion: nil)
    }
    
}

extension ViewController: UINavigationControllerDelegate, UIImagePickerControllerDelegate {
    func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) {
        guard let pickerImage = (info[UIImagePickerController.InfoKey.originalImage] as? UIImage) else { return }
        
        //CropViewControllerを初期化する。pickerImageを指定する。
        let cropController = CropViewController(croppingStyle: .default, image: pickerImage)
        cropController.delegate = self
        
        //AspectRatioのサイズをimageViewのサイズに合わせる。
        cropController.customAspectRatio = imageView.frame.size
        
        //今回は使わない、余計なボタン等を非表示にする。
//        cropController.aspectRatioPickerButtonHidden = true
//        cropController.resetAspectRatioEnabled = false
//        cropController.rotateButtonsHidden = true
        
        //cropBoxのサイズを固定する。
        cropController.cropView.cropBoxResizeEnabled = false
        
        //pickerを閉じたら、cropControllerを表示する。
        picker.dismiss(animated: true) {
            self.present(cropController, animated: true, completion: nil)
        }
    }
    
}