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SegmentImage_Gray

Header:	AVL.h
Namespace:	avl
Module:	FoundationPro

Segments an image into blobs examining differences between neighbouring pixels values.

Applications: Detection of objects of undefined shape, but characterized by uniform brightness and good contrast to the background.

Syntax

void avl::SegmentImage_Gray
(
	const avl::Image& inImage,
	atl::Optional<const avl::Region&> inRoi,
	const float inMaxDifference,
	const avl::BlobsDifferenceMeasure::Type inDifferenceMeasure,
	const int inMinArea,
	atl::Optional<int> inMaxArea,
	atl::Array<avl::Region>& outBlobs
)

Parameters

Name	Type	Range	Default	Description
inImage	const Image&			Image from which blobs are extracted
inRoi	Optional<const Region&>		NIL	Range of pixels to be processed
inMaxDifference	const float	0.0 -	5.0f	Maximal difference between two neighbouring blobs to be merged
inDifferenceMeasure	const BlobsDifferenceMeasure::Type		Neighbour	Measure of blobs difference
inMinArea	const int	0 -	50	Minimal area of a blob
inMaxArea	Optional<int>	0 -	NIL	Maximal area of a blob
outBlobs	Array<Region>&			Blobs extracted from the input image

Description

The filter segments the inImage image into blobs of adjacent pixels which gray values do not differ too much. The classification is different depending on the inDifferenceMeasure method:

if Mean is selected, pixel is considered to belong to an adjacent blob when its value differs by at most inMaxDifference from the mean value of this blob's pixels
if Neighbour is selected, two adjacent pixels are considered to belong to the same blob when their values differ by at most inMaxDifference

Examples

SegmentImage_Gray performed on the sample image with inMaxDifference = 55, inDifferenceMeasure = Mean and inMinArea = 50.

Errors

List of possible exceptions: