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# areaMinMax()

Calculates minimum and maximum color components for a specified area of the image.

```
class func areaMinMax() -> any CIFilter & CIAreaMinMax
```

## Return Value

A 2 x 1 pixel image containing the minimum and maximum color components.

## Discussion

This filter returns the maximum and minimum color components in the region defined by `extent`. The result is a 2 x 1 pixel image with the left pixel containing the minimum components and the right pixel containing the maximum components.

The area min max filter uses the following properties:

- `inputImage`: An image with the type [`CIImage`](/documentation/CoreImage/CIImage).
- `extent`:  A <doc://com.apple.documentation/documentation/CoreFoundation/CGRect> that specifies the subregion of the image that you want to process.

The following code creates a filter that results in a 2 x 1 image where the minimum components are in the left pixel and the maximum components are in the right pixel.

```swift
func areaMinMax(inputImage: CIImage) -> CIImage {
    let filter = CIFilter.areaMinMax()
    filter.inputImage = inputImage
    filter.extent = CGRect(        x: inputImage.extent.width/2-250,
        y: inputImage.extent.height/2-250,
        width: 500,
        height: 500)
    return filter.outputImage!
}
```

![Two images arranged horizontally. The left image contains a photograph of three hydrangea flowers with leaves in the background. A 500 x 500 pixel square in the center of the image is highlighted using an outlined box. The image on the right shows the result of applying the area min-max filter to the 500 x 500 pixel square. This is a 2 x 1 pixel image. The left pixel contains a color made up from the minimum color components. The right pixel contains a color made up from the maximum color components.](images/com.apple.coreimage/media-4331786@2x.png)

---

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