TopHatImage

Header:	AVL.h
Namespace:	avl

Performs a morphological white top hat operation on a image using a predefined kernel.

Syntax

void avl::TopHatImage
(
	const avl::Image& inImage,
	atl::Optional<const avl::Region&> inRoi,
	atl::Optional<const avl::Region&> inSourceRoi,
	atl::Optional<avl::Pixel> inBorderColor,
	avl::KernelShape::Type inKernel,
	int inRadiusX,
	atl::Optional<int> inRadiusY,
	avl::Image& outImage,
	avl::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			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 (2*R+1), or same as inRadiusX
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 brighter than surroundings.

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

Examples

Top 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 TopHatImage.