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BottomHatImage

Header:	FIL.h
Namespace:	fil
Module:	FoundationLite

Performs a morphological black top hat (bottom hat) operation on a image using a predefined kernel.

Syntax

void fil::BottomHatImage
(
	const fil::Image& inImage,
	ftl::Optional<const fil::Region&> inRoi,
	ftl::Optional<const fil::Region&> inSourceRoi,
	ftl::Optional<fil::Pixel> inBorderColor,
	fil::KernelShape::Type inKernel,
	int inRadiusX,
	ftl::Optional<int> inRadiusY,
	fil::Image& outImage,
	fil::Region& diagKernel
)

Parameters

Name	Type	Range	Default	Description
inImage	const Image&			Input image
inRoi	Optional<const Region&>		NIL	Range of outImage pixels to be computed
inSourceRoi	Optional<const Region&>		NIL	Range of inImage pixels to be considered in computations
inBorderColor	Optional<Pixel>		NIL	Color of the imaginary pixels outside the image boundaries
inKernel	KernelShape::Type			Selects kernel shape
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
outImage	Image&			Output image
diagKernel	Region&			Kernel shape

In-place Processing

This function supports in-place data processing - you can pass the same reference to inImage and outImage

Description

Extracts from image small objects that are darker than surroundings.

Is performed by running consecutively two filters. CloseImage to get the image without small objects and SubtractFromImage to remove everything but them.

Examples

Bottom Hat used to remove bigger objects. Used parameters inKernel=Ellipse and inRadiusX=6. Source image on the left and result on the right.

Hardware Acceleration

This operation is optimized for SSE2 technology for pixels of types: all formats (when inSourceRoi = NIL and inBorderColor = NIL).

This operation is optimized for NEON technology for pixels of types: all formats (when inSourceRoi = NIL and inBorderColor = NIL).

This operation supports automatic parallelization for multicore and multiprocessor systems.

Errors

List of possible exceptions:

Error type	Description
DomainError	Region exceeds an input image in BottomHatImage.