GDAL
Public Member Functions | Static Public Attributes
GDALFeaturePoint Class Reference

Class of "feature point" in raster. More...

#include <gdal_simplesurf.h>

List of all members.

Public Member Functions

 GDALFeaturePoint ()
 Standard constructor.
 GDALFeaturePoint (const GDALFeaturePoint &fp)
 Copy constructor.
 GDALFeaturePoint (int nX, int nY, int nScale, int nRadius, int nSign)
 Create instance of GDALFeaturePoint class.
GDALFeaturePointoperator= (const GDALFeaturePoint &point)
double & operator[] (int nIndex)
 Provide access to point's descriptor.
int GetX ()
 Fetch X-coordinate (pixel) of point.
void SetX (int nX)
 Set X coordinate of point.
int GetY ()
 Fetch Y-coordinate (line) of point.
void SetY (int nY)
 Set Y coordinate of point.
int GetScale ()
 Fetch scale of point.
void SetScale (int nScale)
 Set scale of point.
int GetRadius ()
 Fetch radius of point.
void SetRadius (int nRadius)
 Set radius of point.
int GetSign ()
 Fetch sign of Hessian determinant of point.
void SetSign (int nSign)
 Set sign of point.

Static Public Attributes

static const int DESC_SIZE = 64

Detailed Description

Class of "feature point" in raster.

Used by SURF-based algorithm.

This point presents coordinates of distinctive pixel in image. In computer vision, feature points - the most "strong" and "unique" pixels (or areas) in picture, which can be distinguished from others. For more details, see FAST corner detector, SIFT, SURF and similar algorithms.


Constructor & Destructor Documentation

Standard constructor.

Initializes all parameters with negative numbers and allocates memory for descriptor.

Copy constructor.

Parameters:
fpCopied instance of GDALFeaturePoint class
GDALFeaturePoint::GDALFeaturePoint ( int  nX,
int  nY,
int  nScale,
int  nRadius,
int  nSign 
)

Create instance of GDALFeaturePoint class.

Parameters:
nXX-coordinate (pixel)
nYY-coordinate (line)
nScaleScale which contains this point (2, 4, 8, 16 and so on)
nRadiusHalf of the side of descriptor area
nSignSign of Hessian determinant for this point
Note:
This constructor normally is invoked by SURF-based algorithm, which provides all necessary parameters.

Member Function Documentation

Fetch radius of point.

Returns:
Radius for this point.

Fetch scale of point.

Returns:
Scale for this point.

Fetch sign of Hessian determinant of point.

Returns:
Sign for this point.

Fetch X-coordinate (pixel) of point.

Returns:
X-coordinate in pixels

Fetch Y-coordinate (line) of point.

Returns:
Y-coordinate in pixels.
double & GDALFeaturePoint::operator[] ( int  nIndex)

Provide access to point's descriptor.

Parameters:
nIndexPosition of descriptor's value. nIndex should be within range from 0 to DESC_SIZE (in current version - 64)
Returns:
Reference to value of descriptor in 'nIndex' position. If index is out of range then behaviour is undefined.
void GDALFeaturePoint::SetRadius ( int  nRadius)

Set radius of point.

Parameters:
nRadiusRadius for this point.
void GDALFeaturePoint::SetScale ( int  nScale)

Set scale of point.

Parameters:
nScaleScale for this point.
void GDALFeaturePoint::SetSign ( int  nSign)

Set sign of point.

Parameters:
nSignSign of Hessian determinant for this point.
void GDALFeaturePoint::SetX ( int  nX)

Set X coordinate of point.

Parameters:
nXX coordinate in pixels
void GDALFeaturePoint::SetY ( int  nY)

Set Y coordinate of point.

Parameters:
nYY coordinate in pixels.

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

Generated for GDAL by doxygen 1.7.6.1.