Cut a UIImage into a circle

Question

I want to cut a UIImage into a circle so that I can then use it as an annotation. Every answer on this site that I\'ve found describes creating an UIImage

Answer 1

Make sure to import QuarzCore if needed.

 func maskRoundedImage(image: UIImage, radius: CGFloat) -> UIImage {
        let imageView: UIImageView = UIImageView(image: image)
        let layer = imageView.layer
        layer.masksToBounds = true
        layer.cornerRadius = radius
        UIGraphicsBeginImageContext(imageView.bounds.size)
        layer.render(in: UIGraphicsGetCurrentContext()!)
        let roundedImage = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
        return roundedImage!
    }

Answer 2

UIImage extension:

extension UIImage {

    func circularImage(size size: CGSize?) -> UIImage {
        let newSize = size ?? self.size

        let minEdge = min(newSize.height, newSize.width)
        let size = CGSize(width: minEdge, height: minEdge)

        UIGraphicsBeginImageContextWithOptions(size, false, 0.0)
        let context = UIGraphicsGetCurrentContext()

        self.drawInRect(CGRect(origin: CGPoint.zero, size: size), blendMode: .Copy, alpha: 1.0)

        CGContextSetBlendMode(context, .Copy)
        CGContextSetFillColorWithColor(context, UIColor.clearColor().CGColor)

        let rectPath = UIBezierPath(rect: CGRect(origin: CGPoint.zero, size: size))
        let circlePath = UIBezierPath(ovalInRect: CGRect(origin: CGPoint.zero, size: size))
        rectPath.appendPath(circlePath)
        rectPath.usesEvenOddFillRule = true
        rectPath.fill()

        let result = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()

        return result
    }

}

Usage:

UIImageView:

@IBDesignable class CircularImageView: UIImageView {

    override var image: UIImage? {
        didSet {
            super.image = image?.circularImage(size: nil)
        }
    }

}

UIButton:

@IBDesignable class CircularImageButton: UIButton {

    override func setImage(image: UIImage?, forState state: UIControlState) {
        let circularImage = image?.circularImage(size: nil)
        super.setImage(circularImage, forState: state)
    }

}

Answer 3

Xcode 11 • Swift 5.1 or later

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

extension UIImage {
    var isPortrait:  Bool    { size.height > size.width }
    var isLandscape: Bool    { size.width > size.height }
    var breadth:     CGFloat { min(size.width, size.height) }
    var breadthSize: CGSize  { .init(width: breadth, height: breadth) }
    var breadthRect: CGRect  { .init(origin: .zero, size: breadthSize) }
    var circleMasked: UIImage? {
        guard let cgImage = cgImage?
            .cropping(to: .init(origin: .init(x: isLandscape ? ((size.width-size.height)/2).rounded(.down) : 0,
                                              y: isPortrait  ? ((size.height-size.width)/2).rounded(.down) : 0),
                                size: breadthSize)) else { return nil }
        let format = imageRendererFormat
        format.opaque = false
        return UIGraphicsImageRenderer(size: breadthSize, format: format).image { _ in
            UIBezierPath(ovalIn: breadthRect).addClip()
            UIImage(cgImage: cgImage, scale: format.scale, orientation: imageOrientation)
            .draw(in: .init(origin: .zero, size: breadthSize))
        }
    }
}

Playground Testing

let profilePicture = UIImage(data: try! Data(contentsOf: URL(string:"http://i.stack.imgur.com/Xs4RX.jpg")!))!
profilePicture.circleMasked

---

Answer 4

I managed to answer my own question by finding a use of BezierPath!

if let xyz = UIImage(contentsOfFile: readPath) {
     var Rect: CGRect = CGRectMake(0, 0, xyz.size.width, xyz.size.height)
     var x = UIBezierPath(roundedRect: Rect, cornerRadius: 200).addClip()

     UIGraphicsBeginImageContextWithOptions(xyz.size, false, xyz.scale)
     xyz.drawInRect(Rect)
     var ImageNew = UIGraphicsGetImageFromCurrentImageContext()
     UIGraphicsEndImageContext()
     annotation.image = ImageNew
}

Answer 5

I am using RoundedImageView class, the problem facing is that when browse image from gallery the image not show in round or circle.. I simply change the properties of UIImageView/RoundedImageView -> view -> Content Mode -> Aspect Fillsee screenshot

Answer 6

Swift 5.3, Xcode 12.2, Handles all imageOrientations

Based on answer Leo Dabus

Thanks, works perfectly! BUT only for images with imageOrientation .up or .down. For images with .right or .left orientation there are distortions in result. And from iPhone/iPad camera for original photos initially we get .right orientation.

Code below takes into account imageOrientation property:

extension UIImage {

    func cropToCircle() -> UIImage? {
    
        let isLandscape = size.width > size.height
        let isUpOrDownImageOrientation = [0,1,4,5].contains(imageOrientation.rawValue)
    
        let breadth: CGFloat = min(size.width, size.height)
        let breadthSize = CGSize(width: breadth, height: breadth)
        let breadthRect = CGRect(origin: .zero, size: breadthSize)
    
        let xOriginPoint = CGFloat(isLandscape ?
                                (isUpOrDownImageOrientation ? ((size.width-size.height)/2).rounded(.down) : 0) :
                                (isUpOrDownImageOrientation ? 0 : ((size.height-size.width)/2).rounded(.down)))
        let yOriginPoint = CGFloat(isLandscape ?
                                (isUpOrDownImageOrientation ? 0 : ((size.width-size.height)/2).rounded(.down)) :
                                (isUpOrDownImageOrientation ? ((size.height-size.width)/2).rounded(.down) : 0))
    
        guard let cgImage = cgImage?.cropping(to: CGRect(origin: CGPoint(x: xOriginPoint, y: yOriginPoint),
                                                     size: breadthSize)) else { return nil }
        let format = imageRendererFormat
        format.opaque = false
    
        return UIGraphicsImageRenderer(size: breadthSize, format: format).image {_ in
            UIBezierPath(ovalIn: breadthRect).addClip()
            UIImage(cgImage: cgImage, scale: format.scale, orientation: imageOrientation).draw(in: CGRect(origin: .zero, size: breadthSize))
        }
    }
}