Namespace for collection of thresholding functions from the Foundation package. More...

Enumerations
enum class	StaticThresholding { LessThan = CExports::TH_Less , LessThanOrEqual = CExports::TH_LessOrEqual , Equal = CExports::TH_Equal , GreaterOrEqual = CExports::TH_GreaterOrEqual , Greater = CExports::TH_Greater }
	Comparisons for static thresholding. More...

enum class	DynamicThresholdNorm { Mean = CExports::DTN_Mean , MinMax = CExports::DTN_MinMax }
	Norm calculation approaches for dynamic thresholding. More...

Functions
std::unique_ptr< Image >	StaticThreshold (const Image &image, const Image &thresholds, StaticThresholding comparison)
	This function performs thresholding of an input image with pixel-by-pixel thresholds stored in the pixels of a thresholds image. More...

template<class RANGE >
TypedRange< std::unique_ptr< Image >, double, RANGE >::type	StaticThreshold (const Image &image, const RANGE &values, StaticThresholding comparison)
	Create an output image, that is the result of static thresholding. More...

std::unique_ptr< Image >	StaticThreshold (const Image &image, double value, StaticThresholding comparison)
	Create an output image that is the result of static thresholding. More...

std::unique_ptr< Image >	DynamicThreshold (const Image &image, int windowSize, int threshold, DynamicThresholdNorm norm=DynamicThresholdNorm::Mean)
	This function performs dynamic thresholding on the input image. More...

template<class RANGE >
TypedRange< std::unique_ptr< Image >, double, RANGE >::type	StaticTransparentThreshold (const Image &image, const RANGE &thresholds, StaticThresholding comparison, const RANGE &values)
	Create a thresholded image using a transparency approach. More...

std::unique_ptr< Image >	StaticTransparentThreshold (const Image &image, double threshold, StaticThresholding comparison, double value)
	Create a thresholded image using a transparency approach. More...

template<class RANGE >
TypedRange< std::unique_ptr< Image >, double, RANGE >::type	StaticTransparentThreshold (const Image &image, const RANGE &thresholds, StaticThresholding comparison)
	Create a thresholded image using a transparency approach. More...

std::unique_ptr< Image >	StaticTransparentThreshold (const Image &image, double threshold, StaticThresholding comparison)
	Create a thresholded image using a transparency approach. More...

void	RangeThresholdToDst (const ImagePlane &plane, ValueRange< int > range, Image &imageDst, Rect< int > aoi)
	A range based binarization algorithm to the given input. More...

void	RangeThresholdToDst (const ImagePlane &plane, ValueRange< int > range, Image &imageDst)
	A range based binarization algorithm to the given input. More...

std::unique_ptr< Image >	RangeThreshold (const ImagePlane &plane, ValueRange< int > range, Rect< int > aoi)
	A range based binarization algorithm to the given input. More...

std::unique_ptr< Image >	RangeThreshold (const ImagePlane &plane, ValueRange< int > range)
	A range based binarization algorithm to the given input. More...

Detailed Description

Namespace for collection of thresholding functions from the Foundation package.

Remarks: CMake users: Link to imported target CVB::CvbFoundationThreshold

Enumeration Type Documentation

◆ DynamicThresholdNorm

enum class DynamicThresholdNorm

strong

Norm calculation approaches for dynamic thresholding.

Enumerator
Mean	Dynamic thresholding compares versus the mean value of the threshold mask (default).
MinMax	Dynamic thresholding compares versus the middle between the minimum and the maximum value inside the threshold mask.

◆ StaticThresholding

enum class StaticThresholding

strong

Comparisons for static thresholding.

Enumerator
LessThan	Less than.
LessThanOrEqual	Less than or Equal.
Equal	Equal.
GreaterOrEqual	Greater or Equal.
Greater	Greater.

Function Documentation

◆ DynamicThreshold()

std::unique_ptr< Image > DynamicThreshold	(	const Image &	image,
		int	windowSize,
		int	threshold,
		DynamicThresholdNorm	norm = `DynamicThresholdNorm::Mean`
	)

inline

This function performs dynamic thresholding on the input image.

Parameters

[in]	image	Image to be thresholded.
[in]	windowSize	Window size to calculate the dynamic threshold. Bigger window sizes will lead to higher processing times.
[in]	threshold	Threshold offset to use.
[in]	norm	Either DynamicThresholdNorm::Mean (default) or DynamicThresholdNorm::MinMax.

Returns: Thresholded image.

Exceptions

Any	exception derived from std::exception including CvbException.

Dynamic thresholding works by calculating the average gray value over a mask with given size (centered around the pixel in question) for each input pixel. If the difference between this average and the pixel, that is currently being looked at, is above the specified threshold, then the corresponding pixel in the output image is set to white, otherwise it is black.

This function is particularly useful, when dealing with images, that have a non-uniform illumination.

◆ RangeThreshold() [1/2]

std::unique_ptr< Image > RangeThreshold	(	const ImagePlane &	plane,
		ValueRange< int >	range
	)

inline

A range based binarization algorithm to the given input.

Parameters

[in]	plane	Image plane to binarize.
[in]	range	The gray value range for binarization.

Returns: std::unique_ptr<Image> Resulting binarized image.

Exceptions

Any	exception derived from std::exception including CvbException.

The binarization algorithm is implemented in the blob analyzer.

◆ RangeThreshold() [2/2]

std::unique_ptr< Image > RangeThreshold	(	const ImagePlane &	plane,
		ValueRange< int >	range,
		Rect< int >	aoi
	)

inline

A range based binarization algorithm to the given input.

Parameters

[in]	plane	Image plane to binarize.
[in]	range	The gray value range for binarization.
[in]	aoi	Area of interest to binarize.

Returns: std::unique_ptr<Image> Resulting binarized image.

Exceptions

Any	exception derived from std::exception including CvbException.

The binarization algorithm is implemented in the blob analyzer.

◆ RangeThresholdToDst() [1/2]

void RangeThresholdToDst	(	const ImagePlane &	plane,
		ValueRange< int >	range,
		Image &	imageDst
	)

inline

A range based binarization algorithm to the given input.

Parameters

[in]	plane	Image plane to binarize.
[in]	range	The gray value range for binarization.
[in]	imageDst	Destination image to receive the binarization result.

Exceptions

Any	exception derived from std::exception including CvbException.

The binarization algorithm is implemented in the blob analyzer.

This destination image must have one plane only with 8 bits per pixel and be compatible with the input aoi in terms of size.

◆ RangeThresholdToDst() [2/2]

void RangeThresholdToDst	(	const ImagePlane &	plane,
		ValueRange< int >	range,
		Image &	imageDst,
		Rect< int >	aoi
	)

inline

A range based binarization algorithm to the given input.

Parameters

[in]	plane	Image plane to binarize.
[in]	range	The gray value range for binarization.
[in]	imageDst	Destination image to receive the binarization result.
[in]	aoi	Area of interest to binarize.

Exceptions

Any	exception derived from std::exception including CvbException.

The binarization algorithm is implemented in the blob analyzer.

Please note, that despite the fact, that it is possible to specify an area of interest, the binarized data will always be located in the top left corner of the image.

This destination image must have one plane only with 8 bits per pixel and be compatible with the input aoi in terms of size.

◆ StaticThreshold() [1/3]

std::unique_ptr< Image > StaticThreshold	(	const Image &	image,
		const Image &	thresholds,
		StaticThresholding	comparison
	)

inline

This function performs thresholding of an input image with pixel-by-pixel thresholds stored in the pixels of a thresholds image.

Parameters

[in]	image	Image to be thresholded.
[in]	thresholds	Image containing the threshold values for the pixels of the input image.
[in]	comparison	Comparison to apply.

Returns: The thresholded image.

Exceptions

Any	exception derived from std::exception including CvbException.

Both images should be identical in size. However, if they are not, the smallest common rectangle (located at the top left pixel) of both images will be the size of the result image. Both input images should have identical dimensions (either 1 or 3 planes per image) and identical data types.

◆ StaticThreshold() [2/3]

TypedRange< std::unique_ptr< Image >, double, RANGE >::type StaticThreshold	(	const Image &	image,
		const RANGE &	values,
		StaticThresholding	comparison
	)

inline

Create an output image, that is the result of static thresholding.

Parameters

[in]	image	Image to apply static thresholding to.
[in]	values	Threshold values - the array must contain at least one threshold per plane available in the image.
[in]	comparison	Comparison method.

Returns: The result image.

Exceptions

Any	exception derived from std::exception including CvbException.

◆ StaticThreshold() [3/3]

std::unique_ptr< Image > StaticThreshold	(	const Image &	image,
		double	value,
		StaticThresholding	comparison
	)

inline

Create an output image that is the result of static thresholding.

Parameters

[in]	image	Image to apply static thresholding to.
[in]	value	Threshold value to be applied to each image plane.
[in]	comparison	Comparison method.

Returns: Result image.

Exceptions

Any	exception derived from std::exception including CvbException.

◆ StaticTransparentThreshold() [1/4]

TypedRange< std::unique_ptr< Image >, double, RANGE >::type StaticTransparentThreshold	(	const Image &	image,
		const RANGE &	thresholds,
		StaticThresholding	comparison
	)

inline

Create a thresholded image using a transparency approach.

Parameters

[in]	image	Input image.
[in]	thresholds	Thresholds to apply (one per plane).
[in]	comparison	Thresholding condition.

Returns: Thresholded image.

Exceptions

Any	exception derived from std::exception including CvbException.

In the result image every pixel, that violates the comparison to its threshold, will be assigned the threshold value. All others will be assigned the same value, they had in the input image.

◆ StaticTransparentThreshold() [2/4]

TypedRange< std::unique_ptr< Image >, double, RANGE >::type StaticTransparentThreshold	(	const Image &	image,
		const RANGE &	thresholds,
		StaticThresholding	comparison,
		const RANGE &	values
	)

inline

Create a thresholded image using a transparency approach.

Parameters

[in]	image	Input image.
[in]	thresholds	Thresholds to apply (one per plane).
[in]	comparison	Thresholding condition.
[in]	values	Value to set for pixels, that violate the thresholding condition (one per plane required).

Returns: Thresholded image.

Exceptions

Any	exception derived from std::exception including CvbException.

In the result image every pixel, that violates the comparison to its threshold, will be assigned the value specified in values argument. All others will be assigned the same value, they had in the input image.

◆ StaticTransparentThreshold() [3/4]

std::unique_ptr< Image > StaticTransparentThreshold	(	const Image &	image,
		double	threshold,
		StaticThresholding	comparison
	)

inline

Create a thresholded image using a transparency approach.

Parameters

[in]	image	Input image.
[in]	threshold	Threshold to apply to each image plane.
[in]	comparison	Thresholding condition.

Returns: Thresholded image.

Exceptions

Any	exception derived from std::exception including CvbException.

In the result image every pixel, that violates the comparison to its threshold, will be assigned the threshold value. All others will be assigned the same value, they had in the input image.

◆ StaticTransparentThreshold() [4/4]

std::unique_ptr< Image > StaticTransparentThreshold	(	const Image &	image,
		double	threshold,
		StaticThresholding	comparison,
		double	value
	)

inline

Create a thresholded image using a transparency approach.

Parameters

[in]	image	Input image.
[in]	threshold	Threshold value to be applied to each image plane.
[in]	comparison	Thresholding condition.
[in]	value	Value to set for pixels, that violate the thresholding condition (applies to all planes).

Returns: Thresholded image.

Exceptions

Any	exception derived from std::exception including CvbException.

In the result image every pixel, that violates the comparison to its threshold, will be assigned the value specified in values argument. All others will be assigned the same value, they had in the input image.

Enumerations

Functions

Detailed Description

Enumeration Type Documentation

◆ DynamicThresholdNorm

◆ StaticThresholding

Function Documentation

◆ DynamicThreshold()

◆ RangeThreshold() [1/2]

◆ RangeThreshold() [2/2]

◆ RangeThresholdToDst() [1/2]

◆ RangeThresholdToDst() [2/2]

◆ StaticThreshold() [1/3]

◆ StaticThreshold() [2/3]

◆ StaticThreshold() [3/3]

◆ StaticTransparentThreshold() [1/4]

◆ StaticTransparentThreshold() [2/4]

◆ StaticTransparentThreshold() [3/4]

◆ StaticTransparentThreshold() [4/4]