Laplacian filter calculator

1. How is Laplacian calculated?
2. How can we use Laplacian to detect edges from the image?

How is Laplacian calculated?

The Laplacian operator is defined as: V2 = ∂2 ∂x2 + ∂2 ∂y2 + ∂2 ∂z2 . The Laplacian is a scalar operator. If it is applied to a scalar field, it generates a scalar field.

How can we use Laplacian to detect edges from the image?

The Laplacian is a 2-D isotropic measure of the 2nd spatial derivative of an image. The Laplacian of an image highlights regions of rapid intensity change and is therefore often used for edge detection (see zero crossing edge detectors).