Calculates Laplacian of the source image by summing second x- and y- derivatives calculated using Sobel operator.
Specifying aperture_size=1 gives the fastest variant that is equal to convolving the image with the following kernel:
|0 1 0|
|1 -4 1|
|0 1 0|


- apertureSize (Int32)
- Aperture size

The Laplacian of the image