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ThresholdToRegion_RGB

Header:	FIL.h
Namespace:	fil
Module:	FoundationBasic

Creates a region containing image pixels which belongs to the specified range for each individual pixel component.

Applications: Multi-channel thresholding.

Syntax

void fil::ThresholdToRegion_RGB
(
	const fil::Image& inRgbImage,
	ftl::Optional<const fil::Region&> inRoi,
	ftl::Optional<int> inMinRed,
	ftl::Optional<int> inMaxRed,
	ftl::Optional<int> inMinGreen,
	ftl::Optional<int> inMaxGreen,
	ftl::Optional<int> inMinBlue,
	ftl::Optional<int> inMaxBlue,
	ftl::Optional<int> inMinAlpha,
	ftl::Optional<int> inMaxAlpha,
	fil::Region& outRegion
)

Parameters

Name	Type	Range	Default	Description
inRgbImage	const Image&			Input image, usually in the RGB color space
inRoi	Optional<const Region&>		NIL	Region of interest
inMinRed	Optional<int>	0 - 255	128	Minimum for the first pixel component, usually Red (Auto = -INF)
inMaxRed	Optional<int>	0 - 255	NIL	Maximum for the first pixel component, usually Red (Auto = +INF)
inMinGreen	Optional<int>	0 - 255	128	Minimum for the second pixel component, usually Green (Auto = -INF)
inMaxGreen	Optional<int>	0 - 255	NIL	Maximum for the second pixel component, usually Green (Auto = +INF)
inMinBlue	Optional<int>	0 - 255	128	Minimum for the third pixel component, usually Blue (Auto = -INF)
inMaxBlue	Optional<int>	0 - 255	NIL	Maximum for the third pixel component, usually Blue (Auto = +INF)
inMinAlpha	Optional<int>	0 - 255	NIL	Minimum for the fourth pixel component, usually Blue (Auto = -INF)
inMaxAlpha	Optional<int>	0 - 255	NIL	Maximum for the fourth pixel component, usually Blue (Auto = +INF)
outRegion	Region&			Output region

Requirements

For input inRgbImage only pixel formats are supported: 3⨯uint8, 4⨯uint8.

Read more about pixel formats in Image documentation.

Description

The operation is a cousin of ThresholdImage_RGB yet it computes a region instead of an image. The three-channel inRgbImage is considered to be encoded using RGB color representation. The resulting region contains only those pixels of the input image, which meets all of the following conditions:

Intensity of the "red" channel is in range (inMinRed, inMaxRed).
Intensity of the "green" channel is in range (inMinGreen, inMaxGreen).
Intensity of the "blue" channel is in range (inMinBlue, inMaxBlue).

If any of the parameters inMinRed, inMinGreen, inMinBlue is not set, it is assumed to be -infinity.

If any of the parameters inMaxRed, inMaxGreen, inMaxBlue is not set, it is assumed to be infinity.

Examples

ThresholdToRegion_RGB performed on the sample image with inMinRed = 120.0, inMaxGreen = 100.0, inMaxBlue = 100.0.

Hardware Acceleration

This operation is optimized for SSE41 technology for pixels of type: UINT8.

This operation is optimized for NEON technology for pixels of type: UINT8.

This operation supports automatic parallelization for multicore and multiprocessor systems.

Errors

List of possible exceptions:

Error type	Description
DomainError	Not an 8-bit image in ThresholdToRegion_RGB.
DomainError	Region exceeds an input image in ThresholdToRegion_RGB.
DomainError	Unsupported image depth in ThresholdToRegion_RGB.
DomainError	Not supported inRgbImage pixel format in ThresholdToRegion_RGB. Supported formats: 3xUInt8, 4xUInt8.