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# discBlur()

Applies a circle-shaped blur to an area of an image.

```
class func discBlur() -> any CIFilter & CIDiscBlur
```

## Return Value

The blurred image.

## Discussion

This method applies the disc blur filter to an image. The effect targets the pixels within a circle defined by a `radius` and calculates the median color value to create to the output image.

The disc blur filter uses the following properties:

- `radius`: A `float` representing the area of effect as an <doc://com.apple.documentation/documentation/Foundation/NSNumber>.
- `inputImage`: A [`CIImage`](/documentation/CoreImage/CIImage) representing the input image to apply the filter to.

The following code creates a filter that adds a strong blur to the input image:

```swift
    func discBlur(inputImage: CIImage) -> CIImage? {

        let discBlurFilter = CIFilter.discBlur()
        discBlurFilter.inputImage = inputImage
        discBlurFilter.radius = 8
        return discBlurFilter.outputImage
    }
```

![Two photographs of a beach at sunset with multiple palm trees. The photo on the left is clear and crisp. In the photo on the right, a disc blur filter has been applied that creates a strong blur effect on the palm trees in the foreground of the image.](images/com.apple.coreimage/media-3544964@2x.png)

---

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