How to crop the UIImage in iPhone?

Question

In my application, I have set one image in UIImageView and the size of UIImageView is 320 x 170. but the size of original image is 320 x 460. so how to crop this image and d

Answer 1

Maybe someone is interested in the Swift version of the answer @tirth gave. It is written as a UIImage extension. As an example I added another method to crop the image to be a center square version.

    // MARK: - UIImage extension providing function to crop an image to a rect
    extension UIImage {
        /**
         Return a cropped image from an existing image

         - parameter toRect: a rectangular region for a new image

         - returns: new image instance
         */
        func croppedImage(toRect: CGRect) -> UIImage {
            // create new CGImage reference
            let imageRef = CGImageCreateWithImageInRect(self.CGImage, toRect)
            // create and return new UIImage
            return UIImage(CGImage: imageRef!)
        }

        /**
         Crop center rect from possibly rectangular image

         - returns: return self in case image is already square, new center rect otherwise
         */
        func cropCenterRect() -> UIImage {
            // image might already be square
            if self.size.height == self.size.width {
                return self
            }
            // portrait
            if self.size.height > self.size.width {
                // calculate offset at top and bottom
                let offset = (self.size.height - self.size.width) / 2.0
                // return cropped image
                return self.croppedImage(CGRect(x: 0.0, y: offset, width: self.size.width, height: self.size.width))
            } else {
                // landscape
                // calculate offset left and right
                let offset = (self.size.width - self.size.height) / 2.0
                // return cropped image
                return self.croppedImage(CGRect(x: offset, y: 0.0, width: self.size.height, height: self.size.height))
            }
        }
    }