cv::line_descriptor::KeyLine Struct Reference

A class to represent a line. More...

#include <opencv2/line_descriptor/descriptor.hpp>

Public Member Functions
	KeyLine ()
Point2f	getEndPoint () const
Point2f	getEndPointInOctave () const
Point2f	getStartPoint () const
Point2f	getStartPointInOctave () const

Public Attributes
float	angle
int	class_id
float	endPointX
float	endPointY
float	ePointInOctaveX
float	ePointInOctaveY
float	lineLength
int	numOfPixels
int	octave
Point2f	pt
float	response
float	size
float	sPointInOctaveX
float	sPointInOctaveY
float	startPointX
float	startPointY

Detailed Description

A class to represent a line.

As aformentioned, it is been necessary to design a class that fully stores the information needed to characterize completely a line and plot it on image it was extracted from, when required.

KeyLine class has been created for such goal; it is mainly inspired to Feature2d's KeyPoint class, since KeyLine shares some of KeyPoint's fields, even if a part of them assumes a different meaning, when speaking about lines. In particular:

• the class_id field is used to gather lines extracted from different octaves which refer to same line inside original image (such lines and the one they represent in original image share the same class_id value)
• the angle field represents line's slope with respect to (positive) X axis
• the pt field represents line's midpoint
• the response field is computed as the ratio between the line's length and maximum between image's width and height
• the size field is the area of the smallest rectangle containing line

Apart from fields inspired to KeyPoint class, KeyLines stores information about extremes of line in original image and in octave it was extracted from, about line's length and number of pixels it covers.

Constructor & Destructor Documentation

cv::line_descriptor::KeyLine::KeyLine ( )

inline

constructor

Member Function Documentation

Point2f cv::line_descriptor::KeyLine::getEndPoint ( ) const

inline

Returns the end point of the line in the original image

Point2f cv::line_descriptor::KeyLine::getEndPointInOctave ( ) const

inline

Returns the end point of the line in the octave it was extracted from

Point2f cv::line_descriptor::KeyLine::getStartPoint ( ) const

inline

Returns the start point of the line in the original image

Point2f cv::line_descriptor::KeyLine::getStartPointInOctave ( ) const

inline

Returns the start point of the line in the octave it was extracted from

Member Data Documentation

float cv::line_descriptor::KeyLine::angle

orientation of the line

int cv::line_descriptor::KeyLine::class_id

object ID, that can be used to cluster keylines by the line they represent

float cv::line_descriptor::KeyLine::endPointX

float cv::line_descriptor::KeyLine::endPointY

float cv::line_descriptor::KeyLine::ePointInOctaveX

float cv::line_descriptor::KeyLine::ePointInOctaveY

float cv::line_descriptor::KeyLine::lineLength

the length of line

int cv::line_descriptor::KeyLine::numOfPixels

number of pixels covered by the line

int cv::line_descriptor::KeyLine::octave

octave (pyramid layer), from which the keyline has been extracted

Point2f cv::line_descriptor::KeyLine::pt

coordinates of the middlepoint

float cv::line_descriptor::KeyLine::response

the response, by which the strongest keylines have been selected. It's represented by the ratio between line's length and maximum between image's width and height

float cv::line_descriptor::KeyLine::size

minimum area containing line

float cv::line_descriptor::KeyLine::sPointInOctaveX

line's extremes in image it was extracted from

float cv::line_descriptor::KeyLine::sPointInOctaveY

float cv::line_descriptor::KeyLine::startPointX

lines's extremes in original image

float cv::line_descriptor::KeyLine::startPointY

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The documentation for this struct was generated from the following file:

• line_descriptor/include/opencv2/line_descriptor/descriptor.hpp