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fl::DescriptorOrientationHistogram Class Reference

#include <descriptor.h>

Inheritance diagram for fl::DescriptorOrientationHistogram:

List of all members.

Public Methods
	DescriptorOrientationHistogram (float supportRadial=4.5f, int supportPixel=16, float kernelSize=2.5f, int bins=36)
	DescriptorOrientationHistogram (std::istream &stream)
void	computeGradient (const Image &image)
virtual Vector< float >	value (const Image &image, const PointAffine &point)
	Returns a vector of floats that describe the image patch near the interest point.
virtual Image	patch (const Vector< float > &value)
	Return a graphical representation of the descriptor. Preferrably an image patch that would stimulate this descriptor to return the given value.
virtual void	read (std::istream &stream)
virtual void	write (std::ostream &stream, bool withName=true)
Public Attributes
int	supportPixel
	Pixel radius of patch, if needed. Patch size = 2 * supportPixel.
float	kernelSize
	Similar to DescriptorOrientation::kernelSize, except that this class achieves the same effect by raising blur to the appropriate level. Only applies to patches with shape change.
int	bins
	Number of orientation bins in histogram.
float	cutoff
	Ratio of maximum histogram value above which to accept secondary maxima.
void *	lastBuffer
	For detecting change in cached image.
double	lastTime
	For detecting change in cached image.
ImageOf< float >	I_x
ImageOf< float >	I_y

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Detailed Description

Finds characteristic angle of point using a histogram of gradient directions. Follows David Lowe's approach.

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Constructor & Destructor Documentation

DescriptorOrientationHistogram::DescriptorOrientationHistogram (  float    supportRadial = 4.5f, int    supportPixel = 16, float    kernelSize = 2.5f, int    bins = 36 )

DescriptorOrientationHistogram::DescriptorOrientationHistogram (  std::istream &    stream )

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Member Function Documentation

void DescriptorOrientationHistogram::computeGradient (  const Image &    image )

Image DescriptorOrientationHistogram::patch (  const Vector< float > &    value )  [virtual]

Return a graphical representation of the descriptor. Preferrably an image patch that would stimulate this descriptor to return the given value. Implements fl::Descriptor.

void DescriptorOrientationHistogram::read (  std::istream &    stream )  [virtual]

Reimplemented from fl::Descriptor.

Vector< float > DescriptorOrientationHistogram::value (  const Image &    image, const PointAffine &    point )  [virtual]

Returns a vector of floats that describe the image patch near the interest point. Implements fl::Descriptor.

void DescriptorOrientationHistogram::write (  std::ostream &    stream, bool    withName = true )  [virtual]

Reimplemented from fl::Descriptor.

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Member Data Documentation

int fl::DescriptorOrientationHistogram::bins

Number of orientation bins in histogram.

float fl::DescriptorOrientationHistogram::cutoff

Ratio of maximum histogram value above which to accept secondary maxima.

ImageOf<float> fl::DescriptorOrientationHistogram::I_x

ImageOf<float> fl::DescriptorOrientationHistogram::I_y

float fl::DescriptorOrientationHistogram::kernelSize

Similar to DescriptorOrientation::kernelSize, except that this class achieves the same effect by raising blur to the appropriate level. Only applies to patches with shape change.

void* fl::DescriptorOrientationHistogram::lastBuffer

For detecting change in cached image.

double fl::DescriptorOrientationHistogram::lastTime

For detecting change in cached image.

int fl::DescriptorOrientationHistogram::supportPixel

Pixel radius of patch, if needed. Patch size = 2 * supportPixel.

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

• descriptor.h
• DescriptorOrientationHistogram.cc

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