UIImage rounded corners

If you are using a UIImageView to display the image you can simply do the following:

imageView.layer.cornerRadius = 5.0;
imageView.layer.masksToBounds = YES;

And to add a border:

imageView.layer.borderColor = [UIColor lightGrayColor].CGColor;
imageView.layer.borderWidth = 1.0;

I believe that you'll have to import <QuartzCore/QuartzCore.h> and link against it for the above code to work.

I created an UIImage-extension in swift, based on @epatel's great answer:

extension UIImage{
    var roundedImage: UIImage {
        let rect = CGRect(origin:CGPoint(x: 0, y: 0), size: self.size)
        UIGraphicsBeginImageContextWithOptions(self.size, false, 1)
        defer { 
            // End context after returning to avoid memory leak
            UIGraphicsEndImageContext() 
        }
       
        UIBezierPath(
            roundedRect: rect,
            cornerRadius: self.size.height
            ).addClip()
        self.drawInRect(rect)
        return UIGraphicsGetImageFromCurrentImageContext()
    }
}

Tested in a storyboard:

How about these lines...

// Get your image somehow
UIImage *image = [UIImage imageNamed:@"image.jpg"];

// Begin a new image that will be the new image with the rounded corners 
// (here with the size of an UIImageView)
UIGraphicsBeginImageContextWithOptions(imageView.bounds.size, NO, 1.0);

// Add a clip before drawing anything, in the shape of an rounded rect
[[UIBezierPath bezierPathWithRoundedRect:imageView.bounds 
                            cornerRadius:10.0] addClip];
// Draw your image
[image drawInRect:imageView.bounds];

// Get the image, here setting the UIImageView image
imageView.image = UIGraphicsGetImageFromCurrentImageContext();

// Lets forget about that we were drawing
UIGraphicsEndImageContext();