How do I resize the UIImage to reduce upload image size

Question

I've been searching google, and have only come across libraries that either reduce the height/width or some how edit the UIImage appearance via CoreImage. But I have not seen or found one library, post that explains how to reduce image size so when it uploads, it's not the full image size.

so far I have this:

        if image != nil {         //let data = NSData(data: UIImagePNGRepresentation(image))         let data = UIImagePNGRepresentation(image)         body.appendString("--\(boundary)\r\n")         body.appendString("Content-Disposition: form-data; name=\"image\"; filename=\"randomName\"\r\n")         body.appendString("Content-Type: image/png\r\n\r\n")         body.appendData(data)         body.appendString("\r\n")     } 

and it's sending 12MB photos. How can I reduce this to 1mb? thanks!

Answer 1

Xcode 9 • Swift 4 or later

edit/update: For iOS10+ We can use UIGraphicsImageRenderer. For older Swift syntax check edit history.

extension UIImage {     func resized(withPercentage percentage: CGFloat, isOpaque: Bool = true) -> UIImage? {         let canvas = CGSize(width: size.width * percentage, height: size.height * percentage)         let format = imageRendererFormat         format.opaque = isOpaque         return UIGraphicsImageRenderer(size: canvas, format: format).image {             _ in draw(in: CGRect(origin: .zero, size: canvas))         }     }     func resized(toWidth width: CGFloat, isOpaque: Bool = true) -> UIImage? {         let canvas = CGSize(width: width, height: CGFloat(ceil(width/size.width * size.height)))         let format = imageRendererFormat         format.opaque = isOpaque         return UIGraphicsImageRenderer(size: canvas, format: format).image {             _ in draw(in: CGRect(origin: .zero, size: canvas))         }     } } 

Usage:

let image = UIImage(data: try! Data(contentsOf: URL(string:"http://i.stack.imgur.com/Xs4RX.jpg")!))!  let thumb1 = image.resized(withPercentage: 0.1) let thumb2 = image.resized(toWidth: 72.0)