如何在CGImage上进行垂直翻转？

import UIKit
import CoreGraphics

func flipImageVertically(image: UIImage) -> UIImage? {
    guard let cgImage = image.cgImage else { return nil }
    
    // 获取图片的宽度和高度
    let width = cgImage.width
    let height = cgImage.height
    
    // 创建一个位图上下文
    guard let context = CGContext(data: nil, width: width, height: height, bitsPerComponent: cgImage.bitsPerComponent, bytesPerRow: cgImage.bytesPerRow, space: cgImage.colorSpace!, bitmapInfo: cgImage.bitmapInfo.rawValue),
          let flippedCGImage = context.makeImage() else { return nil }
    
    // 设置上下文的变换矩阵，进行垂直翻转
    context.translateBy(x: 0, y: CGFloat(height))
    context.scaleBy(x: 1.0, y: -1.0)
    
    // 绘制图片到上下文中
    context.draw(cgImage, in: CGRect(x: 0, y: 0, width: width, height: height))
    
    // 从上下文中获取翻转后的图片
    guard let finalCGImage = context.makeImage() else { return nil }
    
    // 创建并返回UIImage对象
    return UIImage(cgImage: finalCGImage)
}

// 使用示例
if let originalImage = UIImage(named: "yourImageName"),
   let flippedImage = flipImageVertically(image: originalImage) {
    // 使用flippedImage
}