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OpenRegion

Header:	FIL.h
Namespace:	fil
Module:	FoundationBasic

Performs a morphological opening on a region using a predefined kernel.

Applications: Removing small parts from a region without making it thinner.

Syntax

void fil::OpenRegion
(
	const fil::Region& inRegion,
	fil::KernelShape::Type inKernel,
	int inRadiusX,
	ftl::Optional<int> inRadiusY,
	fil::Region& outRegion
)

Parameters

Name	Type	Range	Default	Description
inRegion	const Region&			Input region
inKernel	KernelShape::Type			Kernel shape (predefined)
inRadiusX	int	0 -	1	Nearly half of the kernel's width (2*R+1)
inRadiusY	Optional<int>	0 -	NIL	Nearly half of the kernel's height (2*R+1), or same as inRadiusX
outRegion	Region&			Output region

Description

The operation performs a morphological opening, which is a tool used for removing thin parts from a region. The operation is a convolution of two basic morphological operations:

Firstly, the input region is eroded using ErodeRegion operation.
Then, the resulting region is dilated using DilateRegion operation.

During the erosion thin parts of a region are eliminated, while further dilation assures that the width of region limbs is preserved.

Both of the component operations are conducted using the same inKernel, inRadiusX and inRadiusY parameters.

Hints

Increase inRadiusX to remove more small parts from the region.
Change inKernel to Ellipse to make the filter work equally strongly in each direction (execution will be slower).

Examples

OpenRegion run with inKernel = Ellipse of dimensions inRadiusX = 3, inRadiusY = 3.

Errors

List of possible exceptions:

Error type	Description
DomainError	Unsupported kernel in OpenRegion.