blendWithAlphaMask()
Blends two images by using an alpha mask image.
Declaration
class func blendWithAlphaMask() -> any CIFilter & CIBlendWithMaskReturn Value
The modified image.
Discussion
This method applies the blend with alpha mask filter to an image. The effect uses values from the grayscale mask image to interpolate between the input and background images. The mask image consists of shades of gray that define the strength of the interpolation from zero (where the mask image is black) to the specified radius (where the mask image is white).
The blend with alpha mask filter uses the following properties:
inputImageAn image with the type CIImage.
maskImageAn image that masks an area on the background image with the type CIImage.
backgroundImageAn image with the type CIImage.
The following code creates a filter that results in the replacement of white in the mask image with the detail of the input image:
func blendWithAlphaMask(inputimage: CIImage, backgroundimage: CIImage, maskimage: CIImage) -> CIImage {
let blendWithAlphaMaskFilter = CIFilter.blendWithAlphaMask()
blendWithAlphaMaskFilter.inputImage = inputimage
blendWithAlphaMaskFilter.maskImage = maskimage
blendWithAlphaMaskFilter.backgroundImage = backgroundimage
return blendWithAlphaMaskFilter.outputImage!
}[Image]