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

# morphologyMinimum()

Blurs a circular area by reducing contrasting pixels.

## Declaration

```swift
class func morphologyMinimum() -> any CIFilter & CIMorphologyMinimum
```

## Return Value

Return Value The blurred image.

## Discussion

Discussion This method applies the morphology minimum filter to an image. The effect targets a circular section of the image, calculating the median color values to find colors that make up more than half the working area. Using this calculation, the effect reduces the pixels with contrasting colors to take up less of the working area. The effect is then repeated throughout the image. The morphology minimum filter uses the following properties: The following code creates a filter that adds a blur that adds darkness to the input image:     func morphologyMinimum(inputImage: CIImage) -> CIImage? {

let morphologyMinimumFilter = CIFilter.morphologyMinimum()         morphologyMinimumFilter.inputImage = inputImage         morphologyMinimumFilter.radius = 5         return morphologyMinimumFilter.outputImage     }

## See Also

### Filters

- [bokehBlur()](coreimage/cifilter-swift.class/bokehblur().md)
- [boxBlur()](coreimage/cifilter-swift.class/boxblur().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)
- [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)