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# lightenBlendMode()

Blends colors from two images by brightening colors.

```
class func lightenBlendMode() -> any CIFilter & CICompositeOperation
```

## Return Value

The modified image.

## Discussion

This method applies the lighten-blend mode filter to an image. The effect replaces any samples in the background image that are darker than input image.

The lighten-blend mode filter uses the following properties:

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

The following code creates a filter that results in the image that blends the input and background image colors:

```swift
func lightenBlendMode(inputImage: CIImage, backgroundImage: CIImage) -> CIImage {
    let colorBlendFilter = CIFilter.lightenBlendMode()
    colorBlendFilter.inputImage = inputImage
    colorBlendFilter.backgroundImage = backgroundImage
    return colorBlendFilter.outputImage!
}
```

![The image on the top left shows a beach with multiple palm trees and a rainbow arching across the blue sky.  The image below is a gradient image displaying a gradual color shift from purple to a dark orange. The image on the right shows the output from applying a lighten blend mode filter. The result displays colors from both images with the brightness of the beach image.](images/com.apple.coreimage/media-3546398@2x.png)

---

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