---
title: blendWithRedMask()
framework: coreimage
role: symbol
role_heading: Type Method
path: coreimage/cifilter-swift.class/blendwithredmask()
---

# blendWithRedMask()

Blends two images by using a red mask image.

## Declaration

```swift
class func blendWithRedMask() -> any CIFilter & CIBlendWithMask
```

## Return Value

Return Value The modified image.

## Discussion

Discussion This method applies the blend with red mask filter to an image. The effect uses values from the red mask image to interpolate between the input and background images. The mask image consists of shades of red that define the strength of the interpolation from zero (where the mask image is black) to the specified radius (where the mask image is red). The blend with red mask filter uses the following properties: The following code creates a filter that results in the replacement of green in the mask image with the detail of the input image: func blendWithRedMask(inputimage: CIImage, backgroundimage: CIImage, maskimage: CIImage) -> CIImage {     let  blendWithRedMaskFilter = CIFilter.blendWithRedMask()     blendWithRedMaskFilter.inputImage = inputimage     blendWithRedMaskFilter.maskImage = maskimage     blendWithRedMaskFilter.backgroundImage = backgroundimage     return blendWithRedMaskFilter.outputImage! }

## See Also

### Filters

- [blendWithAlphaMask()](coreimage/cifilter-swift.class/blendwithalphamask().md)
- [blendWithBlueMask()](coreimage/cifilter-swift.class/blendwithbluemask().md)
- [blendWithMask()](coreimage/cifilter-swift.class/blendwithmask().md)
- [bloom()](coreimage/cifilter-swift.class/bloom().md)
- [cannyEdgeDetector()](coreimage/cifilter-swift.class/cannyedgedetector().md)
- [comicEffect()](coreimage/cifilter-swift.class/comiceffect().md)
- [coreMLModel()](coreimage/cifilter-swift.class/coremlmodel().md)
- [crystallize()](coreimage/cifilter-swift.class/crystallize().md)
- [depthOfField()](coreimage/cifilter-swift.class/depthoffield().md)
- [edges()](coreimage/cifilter-swift.class/edges().md)
- [edgeWork()](coreimage/cifilter-swift.class/edgework().md)
- [gaborGradients()](coreimage/cifilter-swift.class/gaborgradients().md)
- [gloom()](coreimage/cifilter-swift.class/gloom().md)
- [heightFieldFromMask()](coreimage/cifilter-swift.class/heightfieldfrommask().md)
- [hexagonalPixellate()](coreimage/cifilter-swift.class/hexagonalpixellate().md)