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  "title" : "documentEnhancer()"
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# documentEnhancer()

Adjusts an image’s shadows and contrast.

```
class func documentEnhancer() -> any CIFilter & CIDocumentEnhancer
```

## Return Value

The modified image.

## Discussion

This method applies the document enhancer filter to an image. The effect removes unwanted shadows while whitening the background and enhancing contrast. The filter is commonly used to enhance scanned documents.

The document enhancer filter uses the following properties:

- `inputImage`: An image with the type [`CIImage`](/documentation/CoreImage/CIImage).
- `amount`: A `float` representing the desired strength of the effect as an <doc://com.apple.documentation/documentation/Foundation/NSNumber>.

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

```swift
func documentEnhancer(inputImage: CIImage) -> CIImage {
    let documentEnhancerFilter = CIFilter.documentEnhancer()
    documentEnhancerFilter.inputImage = inputImage
    documentEnhancerFilter.amount = 4
    return documentEnhancerFilter.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 document enhancer filter is applied, resulting in a brighter image with less saturation.](images/com.apple.coreimage/media-3545030@2x.png)

---

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