vpCircleHoughTransform::vpCircleHoughTransformParams Class Reference

#include <visp3/imgproc/vpCircleHoughTransform.h>

Public Member Functions
	vpCircleHoughTransformParams ()
	vpCircleHoughTransformParams (const int &gaussianKernelSize, const float &gaussianStdev, const int &gradientFilterKernelSize, const float &lowerCannyThresh, const float &upperCannyThresh, const int &edgeMapFilterNbIter, const std::pair< int, int > &centerXlimits, const std::pair< int, int > &centerYlimits, const float &minRadius, const float &maxRadius, const int &dilatationKernelSize, const int &averagingWindowSize, const float &centerThresh, const float &circleProbabilityThresh, const float &circlePerfectness, const float &centerMinDistThresh, const float &mergingRadiusDiffThresh, const vpImageFilter::vpCannyFilteringAndGradientType &filteringAndGradientMethod=vpImageFilter::CANNY_GBLUR_SOBEL_FILTERING, const vpImageFilter::vpCannyBackendType &backendType=vpImageFilter::CANNY_OPENCV_BACKEND, const float &lowerCannyThreshRatio=0.6f, const float &upperCannyThreshRatio=0.8f, const int &expectedNbCenters=-1, const bool &recordVotingPoints=false, const float &visibilityRatioThresh=0.1f)
int	getGaussianKernelSize () const
float	getGaussianStdev () const
int	getGradientKernelSize () const
float	getLowerCannyThreshold () const
float	getUpperCannyThreshold () const
int	getEdgeMapFilteringNbIter () const
std::pair< int, int >	getCenterXLimits () const
std::pair< int, int >	getCenterYLimits () const
float	getMinRadius () const
float	getMaxRadius () const
int	getDilatationKernelSize () const
int	getAveragingWindowSize () const
float	getCenterMinThreshold () const
int	getExpectedNbCenters () const
float	getProbabilityThreshold () const
float	getVisibilityRatioThreshold () const
float	getCirclePerfectness () const
bool	getRecordVotingPoints () const
float	getCenterMinDist () const
float	getMergingRadiusDiff () const
std::string	toString () const
void	saveConfigurationInJSON (const std::string &jsonPath) const

Static Public Member Functions
static vpCircleHoughTransformParams	createFromJSON (const std::string &jsonFile)

Friends
class	vpCircleHoughTransform
void	from_json (const nlohmann::json &j, vpCircleHoughTransformParams &params)
void	to_json (nlohmann::json &j, const vpCircleHoughTransformParams &params)

Detailed Description

Class that gather the algorithm parameters.

Examples

tutorial-circle-hough.cpp.

Definition at line 70 of file vpCircleHoughTransform.h.

Constructor & Destructor Documentation

vpCircleHoughTransformParams() [1/2]

vpCircleHoughTransform::vpCircleHoughTransformParams::vpCircleHoughTransformParams ( )

inline

Construct a new vpCircleHoughTransformParams object with default parameters.

Definition at line 76 of file vpCircleHoughTransform.h.

vpCircleHoughTransformParams() [2/2]

vpCircleHoughTransform::vpCircleHoughTransformParams::vpCircleHoughTransformParams ( const int &  gaussianKernelSize, const float &  gaussianStdev, const int &  gradientFilterKernelSize, const float &  lowerCannyThresh, const float &  upperCannyThresh, const int &  edgeMapFilterNbIter, const std::pair< int, int > &  centerXlimits, const std::pair< int, int > &  centerYlimits, const float &  minRadius, const float &  maxRadius, const int &  dilatationKernelSize, const int &  averagingWindowSize, const float &  centerThresh, const float &  circleProbabilityThresh, const float &  circlePerfectness, const float &  centerMinDistThresh, const float &  mergingRadiusDiffThresh, const vpImageFilter::vpCannyFilteringAndGradientType &  filteringAndGradientMethod = vpImageFilter::CANNY_GBLUR_SOBEL_FILTERING, const vpImageFilter::vpCannyBackendType &  backendType = vpImageFilter::CANNY_OPENCV_BACKEND, const float &  lowerCannyThreshRatio = 0.6f, const float &  upperCannyThreshRatio = 0.8f, const int &  expectedNbCenters = -1, const bool &  recordVotingPoints = false, const float &  visibilityRatioThresh = 0.1f  )

inline

Construct a new vpCircleHoughTransformParams object.

Parameters

[in]	gaussianKernelSize	Size of the Gaussian filter kernel used to smooth the input image. Must be an odd number.
[in]	gaussianStdev	Standard deviation of the Gaussian filter.
[in]	gradientFilterKernelSize	Size of the Sobel or Scharr kernels used to compute the gradients. Must be an odd number.
[in]	lowerCannyThresh	The lower threshold for the Canny operator. Values lower than this value are rejected. A negative value makes the algorithm compute this threshold and the lower one automatically.
[in]	upperCannyThresh	The upper threshold for the Canny operator. Only values greater than this value are marked as an edge. A negative value makes the algorithm compute this threshold and the lower one automatically.
[in]	edgeMapFilterNbIter	Number of 8-neighbor connectivity filtering iterations to apply to the edge map.
[in]	centerXlimits	Minimum and maximum position on the horizontal axis of the center of the circle we want to detect.
[in]	centerYlimits	Minimum and maximum position on the vertical axis of the center of the circle we want to detect.
[in]	minRadius	Minimum radius of the circles we want to detect.
[in]	maxRadius	Maximum radius of the circles we want to detect.
[in]	dilatationKernelSize	Kernel size of the dilatation that is performed to detect the maximum number of votes for the center candidates.
[in]	averagingWindowSize	Size of the averaging window around the maximum number of votes to compute the center candidate such as it is the barycenter of the window. Must be odd.
[in]	centerThresh	Minimum number of votes a point must exceed to be considered as center candidate.
[in]	circleProbabilityThresh	Probability threshold in order to keep a circle candidate.
[in]	circlePerfectness	The threshold for the colinearity between the gradient of a point and the radius it would form with a center candidate to be able to vote. The formula to get the equivalent angle is: angle = acos(circle_perfectness).
[in]	centerMinDistThresh	Two circle candidates whose centers are closer than this threshold are considered for merging.
[in]	mergingRadiusDiffThresh	Maximum radius difference between two circle candidates to consider merging them.
[in]	filteringAndGradientMethod	The choice of the filter and gradient operator to apply before the edge detection step.
[in]	backendType	Permits to choose the backend used to compute the edge map.
[in]	lowerCannyThreshRatio	If the thresholds must be computed,the lower threshold will be equal to the upper threshold times lowerThresholdRatio .
[in]	upperCannyThreshRatio	If the thresholds must be computed,the upper threshold will be equal to the value such as the number of pixels of the image times upperThresholdRatio have an absolute gradient lower than the upper threshold.
[in]	expectedNbCenters	Expected number of centers in the image. If the number is negative, all the centers are kept. Otherwise, maximum up to this number of centers are kept.
[in]	recordVotingPoints	If true, the edge-map points having voted for each circle will be stored.
[in]	visibilityRatioThresh	Visibility threshold: which minimum ratio of the circle must be visible in order to keep a circle candidate.

Definition at line 147 of file vpCircleHoughTransform.h.

Member Function Documentation

createFromJSON()

static vpCircleHoughTransformParams vpCircleHoughTransform::vpCircleHoughTransformParams::createFromJSON ( const std::string &  jsonFile )

inlinestatic

Create a new vpCircleHoughTransformParams from a JSON file.

Parameters

[in]

jsonFile

The path towards the JSON file.

Returns

vpCircleHoughTransformParams The corresponding vpCircleHoughTransformParams object.

Definition at line 453 of file vpCircleHoughTransform.h.

References vpException::ioError.

getAveragingWindowSize()

int vpCircleHoughTransform::vpCircleHoughTransformParams::getAveragingWindowSize ( ) const

inline

Get the size of the averaging window around the maximum number of votes to compute the center candidate such as it is the barycenter of the window.

Returns

int The size of the averaging window.

Definition at line 318 of file vpCircleHoughTransform.h.

getCenterMinDist()

float vpCircleHoughTransform::vpCircleHoughTransformParams::getCenterMinDist ( ) const

inline

Get the Maximum distance between two circle candidates centers to consider merging them.

Returns

float The maximum distance between two centers.

Definition at line 391 of file vpCircleHoughTransform.h.

getCenterMinThreshold()

float vpCircleHoughTransform::vpCircleHoughTransformParams::getCenterMinThreshold ( ) const

inline

Get the minimum number of votes a point must exceed to be considered as center candidate.

Returns

float The threshold.

Definition at line 328 of file vpCircleHoughTransform.h.

getCenterXLimits()

std::pair<int, int> vpCircleHoughTransform::vpCircleHoughTransformParams::getCenterXLimits ( ) const

inline

Get the minimum and maximum position on the horizontal axis of the center of the circle we want to detect.

Returns

std::pair<int, int> The min and max x positions.

Definition at line 266 of file vpCircleHoughTransform.h.

getCenterYLimits()

std::pair<int, int> vpCircleHoughTransform::vpCircleHoughTransformParams::getCenterYLimits ( ) const

inline

Get the minimum and maximum position on the vertical axis of the center of the circle we want to detect.

Returns

std::pair<int, int> The min and max y positions.

Definition at line 276 of file vpCircleHoughTransform.h.

getCirclePerfectness()

float vpCircleHoughTransform::vpCircleHoughTransformParams::getCirclePerfectness ( ) const

inline

Get the threshold for the colinearity between the gradient of a point and the radius it would form with a center candidate to be able to vote. The formula to get the equivalent angle is: angle = acos(circle_perfectness).

Returns

float The threshold.

Definition at line 371 of file vpCircleHoughTransform.h.

getDilatationKernelSize()

int vpCircleHoughTransform::vpCircleHoughTransformParams::getDilatationKernelSize ( ) const

inline

Get the kernel size of the dilatation that is performed to detect the maximum number of votes for the center candidates.

Returns

int The kernel size.

Definition at line 307 of file vpCircleHoughTransform.h.

getEdgeMapFilteringNbIter()

int vpCircleHoughTransform::vpCircleHoughTransformParams::getEdgeMapFilteringNbIter ( ) const

inline

Get the number of iterations of 8-neighbor connectivity filtering to apply to the edge map.

Returns

int The number of iterations.

Definition at line 256 of file vpCircleHoughTransform.h.

getExpectedNbCenters()

int vpCircleHoughTransform::vpCircleHoughTransformParams::getExpectedNbCenters ( ) const

inline

Get the expected number of centers in the image. If the number is negative, all the centers are kept. Otherwise, maximum up to this number of centers are kept.

Returns

int The expected number of centers.

Definition at line 339 of file vpCircleHoughTransform.h.

getGaussianKernelSize()

int vpCircleHoughTransform::vpCircleHoughTransformParams::getGaussianKernelSize ( ) const

inline

Get the size of the Gaussian filter kernel used to smooth the input image.

Returns

int The size of the kernel.

Definition at line 204 of file vpCircleHoughTransform.h.

getGaussianStdev()

float vpCircleHoughTransform::vpCircleHoughTransformParams::getGaussianStdev ( ) const

inline

Get the standard deviation of the Gaussian filter.

Returns

float The standard deviation.

Definition at line 214 of file vpCircleHoughTransform.h.

getGradientKernelSize()

int vpCircleHoughTransform::vpCircleHoughTransformParams::getGradientKernelSize ( ) const

inline

Get the size of the gradient kernel filters used to compute the gradients.

Returns

int The size of the kernel.

Definition at line 224 of file vpCircleHoughTransform.h.

getLowerCannyThreshold()

float vpCircleHoughTransform::vpCircleHoughTransformParams::getLowerCannyThreshold ( ) const

inline

Get the lower threshold for the Canny operator. Values lower than this value are rejected. A negative value means that the algorithm computes the lower threshold automatically.

Returns

float The lower Canny threshold.

Definition at line 235 of file vpCircleHoughTransform.h.

getMaxRadius()

float vpCircleHoughTransform::vpCircleHoughTransformParams::getMaxRadius ( ) const

inline

Get the maximum radius of the circles we want to detect.

Returns

float The radius max.

Definition at line 296 of file vpCircleHoughTransform.h.

getMergingRadiusDiff()

float vpCircleHoughTransform::vpCircleHoughTransformParams::getMergingRadiusDiff ( ) const

inline

Get the Maximum radius difference between two circle candidates to consider merging them.

Returns

float The merging radius difference.

Definition at line 401 of file vpCircleHoughTransform.h.

getMinRadius()

float vpCircleHoughTransform::vpCircleHoughTransformParams::getMinRadius ( ) const

inline

Get the minimum radius of the circles we want to detect.

Returns

float The radius min.

Definition at line 286 of file vpCircleHoughTransform.h.

getProbabilityThreshold()

float vpCircleHoughTransform::vpCircleHoughTransformParams::getProbabilityThreshold ( ) const

inline

Get the probability threshold in order to keep a circle candidate.

Returns

float The threshold.

Definition at line 349 of file vpCircleHoughTransform.h.

getRecordVotingPoints()

bool vpCircleHoughTransform::vpCircleHoughTransformParams::getRecordVotingPoints ( ) const

inline

Get the boolean indicating if we have to record the edge-map points having voted for the circles.

Returns

bool True if we have to record the voting points.

Definition at line 381 of file vpCircleHoughTransform.h.

getUpperCannyThreshold()

float vpCircleHoughTransform::vpCircleHoughTransformParams::getUpperCannyThreshold ( ) const

inline

Get the upper threshold for the Canny operator. Values lower than this value are rejected. A negative value means that the algorithm computes the lower and upper thresholds automatically.

Returns

float The upper Canny threshold.

Definition at line 246 of file vpCircleHoughTransform.h.

getVisibilityRatioThreshold()

float vpCircleHoughTransform::vpCircleHoughTransformParams::getVisibilityRatioThreshold ( ) const

inline

Get the visibility ratio threshold in order to keep a circle candidate.

Returns

float The threshold.

Definition at line 359 of file vpCircleHoughTransform.h.

saveConfigurationInJSON()

void vpCircleHoughTransform::vpCircleHoughTransformParams::saveConfigurationInJSON ( const std::string &  jsonPath ) const

inline

Save the configuration of the detector in a JSON file described by the path jsonPath. Throw a vpException is the file cannot be created.

Parameters

[in]

jsonPath

The path towards the JSON output file.

Definition at line 487 of file vpCircleHoughTransform.h.

Referenced by vpCircleHoughTransform::saveConfigurationInJSON().

toString()

std::string vpCircleHoughTransform::vpCircleHoughTransformParams::toString ( ) const

inline

Create a string with all the Hough transform parameters.

Definition at line 409 of file vpCircleHoughTransform.h.

References vpImageFilter::vpCannyBackendTypeToString(), and vpImageFilter::vpCannyFiltAndGradTypeToStr().

Referenced by vpCircleHoughTransform::toString().

Friends And Related Function Documentation

from_json

void from_json ( const nlohmann::json &  j, vpCircleHoughTransformParams &  params  )

friend

Read the detector configuration from JSON. All values are optional and if an argument is not present, the default value defined in the constructor is kept.

Parameters

[in]	j	: The JSON object, resulting from the parsing of a JSON file.
[out]	params	: The circle Hough transform parameters that will be initialized from the JSON data.

Definition at line 504 of file vpCircleHoughTransform.h.

to_json

void to_json ( nlohmann::json &  j, const vpCircleHoughTransformParams &  params  )

friend

Parse a vpCircleHoughTransform into JSON format.

Parameters

[out]	j	: A JSON parser object.
[in]	params	: The circle Hough transform parameters that will be serialized in the json object.

Definition at line 583 of file vpCircleHoughTransform.h.

vpCircleHoughTransform

friend class vpCircleHoughTransform

friend

Definition at line 663 of file vpCircleHoughTransform.h.