How to round UIIMage with CGContext

How to round UIIMage with  CGContext

func roundedRectImageFromImage(image:UIImage! ,radious:CGFloat) -> UIImage!{

    

        if(radious == 0.0){

            return image;

        }

    

        if( image != nil) {

            

            let imageWidth:CGFloat = image.size.width;

            let imageHeight:CGFloat = image.size.height;

            

            let rect:CGRect = CGRectMake(0.0, 0.0, imageWidth, imageHeight);

            let window:UIWindow = UIApplication.sharedApplication().windows[0]//[[[UIApplication sharedApplication] windows] objectAtIndex:0];

            let  scale:CGFloat = window.screen.scale;

            UIGraphicsBeginImageContextWithOptions(rect.size,false, scale);

            

            let context:CGContextRef = UIGraphicsGetCurrentContext()!;

            

            CGContextBeginPath(context);

            CGContextSaveGState(context);

            CGContextTranslateCTM (context, CGRectGetMinX(rect), CGRectGetMinY(rect));

            CGContextScaleCTM (context, radious, radious);

            

            let rectWidth:CGFloat = CGRectGetWidth (rect)/radious;

            let rectHeight:CGFloat = CGRectGetHeight (rect)/radious;

            

            CGContextMoveToPoint(context, rectWidth, rectHeight/2.0);

            CGContextAddArcToPoint(context, rectWidth, rectHeight, rectWidth/2.0, rectHeight, radious);

            CGContextAddArcToPoint(context, 0.0, rectHeight, 0.0, rectHeight/2.0, radious);

            CGContextAddArcToPoint(context, 0.0, 0.0, rectWidth/2.0, 0.0, radious);

            CGContextAddArcToPoint(context, rectWidth, 0.0, rectWidth, rectHeight/2.0, radious);

            CGContextRestoreGState(context);

            CGContextClosePath(context);

            CGContextClip(context);

            

            image.drawInRect(CGRectMake(0.0, 0.0, imageWidth, imageHeight))

           

            let newImage:UIImage = UIGraphicsGetImageFromCurrentImageContext();

            UIGraphicsEndImageContext();

            

            return newImage;

        }

        

        return nil;

    }

used:

let  imageView = UIImageView(frame: CGRectMake(200,200,100,100));

        imageView.image = roundedRectImageFromImage(UIImage(named: "name.jpg"),radious:6)