UIImage+Resize.swift

import CoreGraphics
import UIKit
import AVFoundation

extension UIImage {
	
	func resized(within newSize: CGSize, outputScale: CGFloat? = nil) -> UIImage {
		let originalSize = self.size
		
		let withinBounds = CGRect(x: 0, y: 0, width: newSize.width, height: newSize.height)
		
		var newFrame = AVMakeRect(aspectRatio: originalSize, insideRect: withinBounds)
		newFrame.origin = CGPoint.zero
		
		let format = UIGraphicsImageRendererFormat.preferred()
		
		if let scale = outputScale {
			format.scale = scale
		}
		
		let renderer = UIGraphicsImageRenderer(size: newFrame.size, format: format)
		
		let image = renderer.image(actions: { context in
			self.draw(in: newFrame)
		})
		
		return image
	}
	
}