Image compression

UIImage+Extensions.swift

public extension UIImage {
    
    func compress() -> UIImage? {
        var actualHeight = self.size.height
        var actualWidth = self.size.width
        let maxHeight: CGFloat = 800.0
        let maxWidth: CGFloat = 800.0
        var imgRatio = actualWidth/actualHeight
        let maxRatio = maxWidth/maxHeight
        var compressionQuality: CGFloat = 0.6
        
        if actualHeight > maxHeight || actualWidth > maxWidth {
            if imgRatio < maxRatio {
                //Adjust width according to maxHeight
                imgRatio = maxHeight / actualHeight
                actualWidth = imgRatio * actualWidth
                actualHeight = maxHeight
            } else if imgRatio > maxRatio {
                //Adjust height according to maxWidth
                imgRatio = maxWidth / actualWidth
                actualHeight = imgRatio * actualHeight
                actualWidth = maxWidth
            } else {
                actualHeight = maxHeight
                actualWidth = maxWidth
            }
        } else {
            compressionQuality = 1
        }
        
        // Draw
        let rect = CGRect(x: 0, y: 0, width: actualWidth, height: actualHeight)
        UIGraphicsBeginImageContext(rect.size)
        self.draw(in: rect)

        if let img = UIGraphicsGetImageFromCurrentImageContext(),
            let imageData = UIImageJPEGRepresentation(img, CGFloat(compressionQuality)) {
            
            UIGraphicsEndImageContext()
            return UIImage(data: imageData)
        }
        
        UIGraphicsEndImageContext()
        return nil
    }
}