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# sourceOverCompositing()

Places one image over a second image.

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

## Return Value

The modified image.

## Discussion

This method applies the source-over compositing filter to an image. The effect creates the result by overlaying the input image over the background image. Unlike the other source compositing filters, source-over doesn’t subtract parts of the image.

The source-over compositing 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 both of the input images becoming visible with no subtraction:

```swift
func sourceOverCompositing(inputImage: CIImage, backgroundImage: CIImage) -> CIImage {
    let colorBlendFilter = CIFilter.sourceOverCompositing()
    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 source-over compositing filter. The gradient image is overlaid on the beach photo image.](images/com.apple.coreimage/media-3546395@2x.png)

---

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