vImageFlatten_ARGBFFFF(_:_:_:_:_:)

Declaration

func vImageFlatten_ARGBFFFF(_ argbSrc: UnsafePointer<vImage_Buffer>, _ argbDst: UnsafePointer<vImage_Buffer>, _ argbBackgroundColorPtr: UnsafePointer<Float>, _ isImagePremultiplied: Bool, _ flags: vImage_Flags) -> vImage_Error

Parameters

argbSrc

A pointer to a vImage buffer that references floating-point ARGB interleaved source pixels.

argbDst

A pointer to a vImage buffer data structure. You're responsible for filling out the height, width, and rowBytes fields of this structure, and for allocating a data buffer of the appropriate size. On return, the data buffer this structure points to contains the destination image data. When you no longer need the data buffer, you must deallocate the memory.

argbBackgroundColorPtr

A pointer to Pixel_FFFF that references floating-point ARGB premultiplied background color.

isImagePremultiplied

True if the source image is premultiplied; otherwise, false.

flags

The options to use when performing the operation. If you plan to perform your own tiling or use multithreading, pass kvImageDoNotTile.

Return Value

Discussion

 resultAlpha = pixelAlpha + (1 - pixelAlpha) * backgroundAlpha
 if(isImagePremultiplied)
 {
     resultColor = pixelColor + (1 - pixelAlpha) * backgroundColor
 }
 else
 {
     resultColor = pixelColor * pixelAlpha + (1 - pixelAlpha) * backgroundColor
 }