Class-level extension for UIImage that allow to resize input image based on expected image width or/and height. Swift 3

UIImage+Resize.swift

extension UIImage {
    class func resize(_ image: UIImage, newWidth: CGFloat) -> UIImage? {
        
        let scale = newWidth / image.size.width
        let newHeight = image.size.height * scale
        UIGraphicsBeginImageContext(CGSize(width: newWidth, height: newHeight))
        image.draw(in: CGRect(x: 0, y: 0, width: newWidth, height: newHeight))
        let newImage = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
        
        return newImage
    }
    
    class func resize(_ image: UIImage, newHeight: CGFloat) -> UIImage? {

        let scale = newHeight / image.size.height
        let newWidth = image.size.width * scale
        UIGraphicsBeginImageContext(CGSize(width: newWidth, height: newHeight))
        image.draw(in: CGRect(x: 0, y: 0, width: newWidth, height: newHeight))
        let newImage = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
        
        return newImage
    }

    class func resize(_ image: UIImage, newSize: CGSize) -> UIImage? {
        
        UIGraphicsBeginImageContext(newSize)
        image.draw(in: CGRect(x: 0, y: 0, width: newSize.width, height: newSize.height))
        let newImage = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
        
        return newImage
    }
    
}