         didSet{
             if let maskImage = maskImage {
                 let _maskView = UIImageView()
+                _maskView.contentMode = .Center
                 _maskView.image = maskImage
                 maskView = _maskView
             } else {

        }
        set(image){
            let imageView = UIImageView.init()
            imageView.contentMode = .ScaleToFill
            imageView.image = image
            overlayView = imageView
        }

        }
        set(image){
            let imageView = UIImageView.init()
            imageView.contentMode = .Center
            imageView.image = image
            backgroundView = imageView
        }
