8.5.6 Top Hat transformation

The filter subtracts the opened image from the original one (“TopHat” transformation). It shows areas which are lighter than others and is used for their isolation. It is useful for marking details on the half-hue image.

You can use TopHat and Black Hat transformations together for increasing the contrast.

Filter parameters:

• Size;
• Iteration.

Size (size) parameter determines the area of the filter influence around each point.

Iteration (iteration) parameter determines the amount of iterations.