Adding blur effect to background in swift

Question

I am setting a background image to view controller. But also i want to add blur effect to this background. How can I do this?

I am setting background with following

Answer 1

U can also use CoreImage to create blurred image with dark effect

1. Make snapshot for image

   func snapShotImage() -> UIImage {
       UIGraphicsBeginImageContext(self.frame.size)
       if let context = UIGraphicsGetCurrentContext() {
           self.layer.renderInContext(context)
           let image = UIGraphicsGetImageFromCurrentImageContext()
           UIGraphicsEndImageContext()
           return image
       }
   
       return UIImage()
   }
   

2. Apply CoreImage Filters as u wish with

   private func bluredImage(view:UIView, radius:CGFloat = 1) -> UIImage {
   let image = view.snapShotImage()
   
   if let source = image.CGImage {
       let context = CIContext(options: nil)
       let inputImage = CIImage(CGImage: source)
   
       let clampFilter = CIFilter(name: "CIAffineClamp")
       clampFilter?.setDefaults()
       clampFilter?.setValue(inputImage, forKey: kCIInputImageKey)
   
       if let clampedImage = clampFilter?.valueForKey(kCIOutputImageKey) as? CIImage {
           let explosureFilter = CIFilter(name: "CIExposureAdjust")
           explosureFilter?.setValue(clampedImage, forKey: kCIInputImageKey)
           explosureFilter?.setValue(-1.0, forKey: kCIInputEVKey)
   
           if let explosureImage = explosureFilter?.valueForKey(kCIOutputImageKey) as? CIImage {
               let filter = CIFilter(name: "CIGaussianBlur")
               filter?.setValue(explosureImage, forKey: kCIInputImageKey)
               filter?.setValue("\(radius)", forKey:kCIInputRadiusKey)
   
               if let result = filter?.valueForKey(kCIOutputImageKey) as? CIImage {
                   let bounds = UIScreen.mainScreen().bounds
                   let cgImage = context.createCGImage(result, fromRect: bounds)
                   let returnImage = UIImage(CGImage: cgImage)
                   return returnImage
               }
           }
       }
   }
   return UIImage()
   }