OpenCV  3.3.0
Open Source Computer Vision
Public Member Functions | Static Public Member Functions | List of all members
cv::line_descriptor::LSDDetector Class Reference

#include "descriptor.hpp"

Inheritance diagram for cv::line_descriptor::LSDDetector:
cv::Algorithm

Public Member Functions

 LSDDetector ()
 
void detect (const Mat &image, std::vector< KeyLine > &keypoints, int scale, int numOctaves, const Mat &mask=Mat())
 Detect lines inside an image. More...
 
void detect (const std::vector< Mat > &images, std::vector< std::vector< KeyLine > > &keylines, int scale, int numOctaves, const std::vector< Mat > &masks=std::vector< Mat >()) const
 
- Public Member Functions inherited from cv::Algorithm
 Algorithm ()
 
virtual ~Algorithm ()
 
virtual void clear ()
 Clears the algorithm state. More...
 
virtual bool empty () const
 Returns true if the Algorithm is empty (e.g. in the very beginning or after unsuccessful read. More...
 
virtual String getDefaultName () const
 
virtual void read (const FileNode &fn)
 Reads algorithm parameters from a file storage. More...
 
virtual void save (const String &filename) const
 
virtual void write (FileStorage &fs) const
 Stores algorithm parameters in a file storage. More...
 

Static Public Member Functions

static Ptr< LSDDetectorcreateLSDDetector ()
 Creates ad LSDDetector object, using smart pointers. More...
 
- Static Public Member Functions inherited from cv::Algorithm
template<typename _Tp >
static Ptr< _Tp > load (const String &filename, const String &objname=String())
 Loads algorithm from the file. More...
 
template<typename _Tp >
static Ptr< _Tp > loadFromString (const String &strModel, const String &objname=String())
 Loads algorithm from a String. More...
 
template<typename _Tp >
static Ptr< _Tp > read (const FileNode &fn)
 Reads algorithm from the file node. More...
 

Additional Inherited Members

- Protected Member Functions inherited from cv::Algorithm
void writeFormat (FileStorage &fs) const
 

Detailed Description

Lines extraction methodology

The lines extraction methodology described in the following is mainly based on [183] . The extraction starts with a Gaussian pyramid generated from an original image, downsampled N-1 times, blurred N times, to obtain N layers (one for each octave), with layer 0 corresponding to input image. Then, from each layer (octave) in the pyramid, lines are extracted using LSD algorithm.

Differently from EDLine lines extractor used in original article, LSD furnishes information only about lines extremes; thus, additional information regarding slope and equation of line are computed via analytic methods. The number of pixels is obtained using LineIterator. Extracted lines are returned in the form of KeyLine objects, but since extraction is based on a method different from the one used in BinaryDescriptor class, data associated to a line's extremes in original image and in octave it was extracted from, coincide. KeyLine's field class_id is used as an index to indicate the order of extraction of a line inside a single octave.

Constructor & Destructor Documentation

§ LSDDetector()

cv::line_descriptor::LSDDetector::LSDDetector ( )
inline

Member Function Documentation

§ createLSDDetector()

static Ptr<LSDDetector> cv::line_descriptor::LSDDetector::createLSDDetector ( )
static

Creates ad LSDDetector object, using smart pointers.

§ detect() [1/2]

void cv::line_descriptor::LSDDetector::detect ( const Mat image,
std::vector< KeyLine > &  keypoints,
int  scale,
int  numOctaves,
const Mat mask = Mat() 
)

Detect lines inside an image.

Parameters
imageinput image
keypointsvector that will store extracted lines for one or more images
scalescale factor used in pyramids generation
numOctavesnumber of octaves inside pyramid
maskmask matrix to detect only KeyLines of interest

§ detect() [2/2]

void cv::line_descriptor::LSDDetector::detect ( const std::vector< Mat > &  images,
std::vector< std::vector< KeyLine > > &  keylines,
int  scale,
int  numOctaves,
const std::vector< Mat > &  masks = std::vector< Mat >() 
) const

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Parameters
imagesinput images
keylinesset of vectors that will store extracted lines for one or more images
scalescale factor used in pyramids generation
numOctavesnumber of octaves inside pyramid
masksvector of mask matrices to detect only KeyLines of interest from each input image

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