stira::imageanalysis::HOG Class Reference

Class to compute Image descriptor based on Histogram of Orientated Gradients (HOG) for gray-level images References: - https://software.intel.com/en-us/node/529070. More...

#include <HOG.h>

Public Member Functions
	HOG (Image *pImage, common::RectangularROI< int > myRoi, int cellWidth, int cellHeight, int nrBins)
	constructor More...
void	ComputeHogDescriptor (std::vector< double > &descriptorValues)
	computes the HOG descriptor for the given ROI image More...
Image *	VisualizeHogDescriptor (std::vector< double > &descriptorValues, int winWidth, int winHeight, double scaleFactor, double viz_factor)
	visualization of HOG descriptor method More...

Detailed Description

Class to compute Image descriptor based on Histogram of Orientated Gradients (HOG) for gray-level images References: - https://software.intel.com/en-us/node/529070.

• http://stackoverflow.com/questions/32417531/hog-what-is-done-in-the-contrast-normalization-step TODO: further implement rest of SIFT: http://www.vlfeat.org/api/sift.html

Constructor & Destructor Documentation

stira::imageanalysis::HOG::HOG	(	Image *	pImage,
		common::RectangularROI< int >	myRoi,
		int	cellWidth,
		int	cellHeight,
		int	nrBins
	)

constructor

Parameters

pImage	input image
myRoi	Region of Interest to compute descriptor for (currently not used; HOG descriptor is computed for whole image)
cellWidth	width of single cell in HOG
cellHeight	height of single cell in HOG
nrBins	number of bins for orientation histogram in single cell ;

References stira::imagedata::OrientationGrid::GetOrientationVector(), stira::imagedata::ArrayGrid< T >::GetValue(), stira::imagedata::OrientationGrid::SetAngle(), and stira::imagedata::OrientationGrid::SetMagnitude().

Member Function Documentation

void stira::imageanalysis::HOG::ComputeHogDescriptor

(

std::vector< double > &

descriptorValues

)

computes the HOG descriptor for the given ROI image

Parameters

descriptorValues

output vector containing the output descriptor values

References stira::common::MathUtils::NormalizeVector().

Image * stira::imageanalysis::HOG::VisualizeHogDescriptor	(	std::vector< double > &	descriptorValues,
		int	winWidth,
		int	winHeight,
		double	scaleFactor,
		double	viz_factor
	)

visualization of HOG descriptor method

Parameters

descriptorValues	vector containing the descriptor values to be visualized
winWidth	width of window to be visualized
winHeight	height of window to be visualized
scaleFactor	factor to scale whole visualization grid
viz_factor	factor to stretch the line of the HOG per cell with for easier visualization

References stira::imagedata::Image::Clone(), stira::imagetools::DrawImageTools::DrawLine(), and stira::imagetools::DrawImageTools::DrawRectangle().

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

• imageanalysis/imageanalysis/HOG.h
• imageanalysis/imageanalysis/HOG.cpp