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# maximumComponent()

Creates a maximum RGB grayscale image.

```
class func maximumComponent() -> any CIFilter & CIMaximumComponent
```

## Return Value

The modified image.

## Discussion

This method applies the maximum component filter to an image. The effect applies a preconfigured set of effects that result in the input image becoming grayscale using the maximum RGB color components.

The maximum component filter uses the following property:

- `inputImage`: An image with the type [`CIImage`](/documentation/CoreImage/CIImage).

The following code creates a filter that adds brightness and makes the input image grayscale:

```swift
func maximumComponent(inputImage: CIImage) -> CIImage {
    let maximumComponentFilter = CIFilter.maximumComponent()
    maximumComponentFilter.inputImage = inputImage
    return maximumComponentFilter.outputImage!
}
```

![Two pictures of a pink flower surrounded by foliage. The photo on the left shows a single flower photographed close-up, in focus, with good light and no effects. In the photo on the right, a maximum component filter is applied, transforming the colors in the image to be grayscale.](images/com.apple.coreimage/media-3545023@2x.png)

---

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