---
title: boxBlur()
framework: coreimage
role: symbol
role_heading: Type Method
path: coreimage/cifilter-swift.class/boxblur()
---

# boxBlur()

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

## Declaration

```swift
class func boxBlur() -> any CIFilter & CIBoxBlur
```

## Return Value

Return Value The blurred image.

## Discussion

Discussion This method applies the box blur filter to an image. The effect targets a square area and calculates the median color value of the pixels to create the output image. The radius is the width of a square area with a larger area, resulting in a stronger blur effect on the output image. The box blur filter uses the following properties: The following code creates a filter that results in less detail in the input image:     func boxBlur(inputImage: CIImage) -> CIImage? {

let boxBlurFilter = CIFilter.boxBlur()         boxBlurFilter.inputImage = inputImage         boxBlurFilter.radius = 10         return boxBlurFilter.outputImage     }

## See Also

### Filters

- [bokehBlur()](coreimage/cifilter-swift.class/bokehblur().md)
- [discBlur()](coreimage/cifilter-swift.class/discblur().md)
- [gaussianBlur()](coreimage/cifilter-swift.class/gaussianblur().md)
- [maskedVariableBlur()](coreimage/cifilter-swift.class/maskedvariableblur().md)
- [median()](coreimage/cifilter-swift.class/median().md)
- [morphologyGradient()](coreimage/cifilter-swift.class/morphologygradient().md)
- [morphologyMaximum()](coreimage/cifilter-swift.class/morphologymaximum().md)
- [morphologyMinimum()](coreimage/cifilter-swift.class/morphologyminimum().md)
- [morphologyRectangleMaximum()](coreimage/cifilter-swift.class/morphologyrectanglemaximum().md)
- [morphologyRectangleMinimum()](coreimage/cifilter-swift.class/morphologyrectangleminimum().md)
- [motionBlur()](coreimage/cifilter-swift.class/motionblur().md)
- [noiseReduction()](coreimage/cifilter-swift.class/noisereduction().md)
- [zoomBlur()](coreimage/cifilter-swift.class/zoomblur().md)