vImage.BlendMode.multiply
Sets the destination pixel as the product of the corresponding source pixels.
Declaration
case multiplyDiscussion
The following image shows the result of compositing using the multiply blend mode:
[Image]
The bottom-right quadrant in the result is black because the operation multiplies each bottom-layer pixel value by 0.0 from the top layer.
The top-left quadrant in the result is identical to the corresponding quadrant in the bottom layer because the operation multiplies each bottom-layer pixel value by 1.0.
The top-right quadrant in the result is darker than the corresponding quadrant in the bottom layer. In this quadrant, the top-layer and bottom-layer pixel values are identical. For example, if the source pixel value is 0.5, the destination pixel value is 0.25:
dest = 0.5 * 0.5 // dest = 0.25