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  "framework" : "CoreImage",
  "identifier" : "/documentation/CoreImage/CIFilter-swift.class/luminosityBlendMode()",
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  "title" : "luminosityBlendMode()"
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# luminosityBlendMode()

Blends color from two images by calculating the color, hue, and saturation.

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

## Return Value

The modified image.

## Discussion

This method applies the luminosity-blend mode filter to an image. The effect creates the output image by using the hue and saturation values of the background image while using the luminance values of the input image.

The luminosity-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 having accurate gray colors while other colors are added from the background image:

```swift
func luminosityBlendMode(inputImage: CIImage, backgroundImage: CIImage) -> CIImage {
    let colorBlendFilter = CIFilter.luminosityBlendMode()
    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 luminosity-blend-mode filter. The result displays brightness of the beach image and the colors of the gradient image.](images/com.apple.coreimage/media-3546410@2x.png)

---

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