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ThresholdToRegion_Color

Header:	AVL.h
Namespace:	avl

Creates a region containing image pixels with values close to the given color.

Syntax

void avl::ThresholdToRegion_Color
(
	const avl::Image& inImage,
	atl::Optional<const avl::Region&> inRoi,
	const avl::Pixel& inRgbColor,
	float inChromaAmount,
	float inMaxDifference,
	float inHysteresis,
	avl::Region& outRegion
)

Parameters

Name	Type	Range	Default	Description
inImage	const Image&			Input image
inRoi	Optional<const Region&>		NIL	Region of interest
inRgbColor	const Pixel&			Color to compare the image to
inChromaAmount	float	0.0 - 1.0	0.7f	Proportion of chromatic information in distance computation
inMaxDifference	float	0.0 -	5.0f	Maximum difference between image pixel and model color
inHysteresis	float	0.0 -	0.0f	Defines how much the difference criterium is lowered for pixels neighboring with other foreground pixels
outRegion	Region&			Output region

Requirements

For input inImage only pixel formats are supported: 1⨯uint8, 2⨯uint8, 3⨯uint8, 4⨯uint8.

Read more about pixel formats in Image documentation.

Hints

Define the reference color by setting the inRgbColor input.
Increase inChromaAmount to make the filter less sensitive to changes in brightness. Decrease it to make brightness more important.
Set inMaxDifference experimentally to a value that best separates the foreground and background pixels.

Examples

ThresholdToRegion_Color performed on a sample image with inRgbColor = (192, 34, 22), inChromaAmount = 1.0, inMaxDifference = 48.

Hardware Acceleration

This operation is optimized for SSE2 technology for pixels of types: 1xUINT8, 3xUINT8.

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 ThresholdToRegion_Color.
DomainError	Not supported inImage pixel format in ThresholdToRegion_Color.