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ThresholdImage_Color

Header:	AVL.h
Namespace:	avl
Module:	FoundationPro

Transforms each pixel value to maximum or minimum depending on the distance from a given color.

Applications: Color analysis with a given reference color.

Syntax

void avl::ThresholdImage_Color
(
	const avl::Image& inImage,
	atl::Optional<const avl::Region&> inRoi,
	const avl::Pixel& inRgbColor,
	float inChromaAmount,
	float inMaxDifference,
	float inFuzziness,
	avl::Image& outMonoImage
)

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
inFuzziness	float	0.0 -	0.0f	A tolerance for computed difference that results in intermediate output values
outMonoImage	Image&

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 function 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.
Use inFuzziness to add some smooth transitions between black and white pixels in the result.

Examples

ThresholdImage_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 (for inFuzziness = 0), 3xUINT8 (for inFuzziness = 0).

This operation is optimized for NEON technology for pixels of types: 1xUINT8 (for inFuzziness = 0), 3xUINT8 (for inFuzziness = 0).

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 ThresholdImage_Color.
DomainError	Not supported inImage pixel format in ThresholdImage_Color. Supported formats: 1xUInt8, 2xUInt8, 3xUInt8, 4xUInt8.