问如何在Swift中更改作为blendKernel.apply函数输入的CIImage掩码的大小

EN

class IntegrateViewAndMask {
    var blendKernel: CIBlendKernel { return .softLight }

    func mergeMaskAndBackground(mask: UIImage, background: CVPixelBuffer, size: Int) -> UIImage? {
        // Merge two images
//        let sizeImage = CGSize(width: size, height: size)

//        UIGraphicsBeginImageContext(sizeImage)

//        let areaSize = CGRect(x: 0, y: 0, width: sizeImage.width, height: sizeImage.height)

        // background
        var background = UIImage(pixelBuffer: background)

//      crop image to square 1080 x 1080
        background = cropImageToSquare(image:background!)

//        background?.draw(in: areaSize)

        // mask
//        mask.draw(in: areaSize)

        let backgroundCI = CIImage(image: background!)

        let maskCI = CIImage(image: mask)

        let trialImage = blendKernel.apply(foreground: maskCI!, background: backgroundCI!)

        let trialImageUI = UIImage(ciImage:trialImage!)

//        let newImage:UIImage = UIGraphicsGetImageFromCurrentImageContext()!

//        UIGraphicsEndImageContext()

        return trialImageUI