NICE_VisLearning/features/gradientfeatures/PHOGFeature.cpp

/** 
* @file PHOGFeature.cpp
* @brief Implementation of the PHOG-Features and corresponding Kernel as done by Anna Bosch et al.
* @author Alexander Lütz
* @date 15/11/2011
*/

#include "PHOGFeature.h"

using namespace std;
using namespace OBJREC;
using namespace NICE;

/** protected things*/
/**
* @brief Calculates the PHOG-Pyramide for given gradient images (idea of Anna Bosch and Andrew Zisserman)
* @author Alexander Lütz
* @date 15/11/2011
*/
void PHOGFeature::calculate_PHOG_Pyramide(const NICE::Image & gradient_orientations, const NICE::ImageT<float> & gradient_magnitudes, std::vector< std::vector<float> > & PHOG_descriptor)
{
	float sum_of_all = 0.0;
	float sum_of_level = 0.0;

	std::vector<float> one_collecting_vector;
	one_collecting_vector.clear();
	std::vector<float> HoG (number_Of_Bins);
	for (int j = 0; j < gradient_orientations.height(); j++)
		for (int i = 0; i < gradient_orientations.width(); i++)
		{
			int orientation (gradient_orientations(i,j));
			if (( (orientation<0) || ((uint)orientation>=HoG.size())) && verbose)
			{
				cerr << "orientation is " << orientation << " and does not fit to HoG.size(): " << HoG.size() << endl;
				cerr << "i: " << i << " j: " << j << " gradient_orientations.width() : " <<  gradient_orientations.width() << " gradient_orientations.height() : " << gradient_orientations.height() << endl;
			}
			HoG[gradient_orientations(i,j)] += gradient_magnitudes(i,j);
			sum_of_all += gradient_magnitudes(i,j);
			sum_of_level += gradient_magnitudes(i,j);
		}
		
	switch(histrogram_concatenation)
	{
		case 0:
		{
			if (sum_of_level != 0.0)  //normalize the descriptor-entries
			{
				for (std::vector<float>::iterator HoG_it = HoG.begin(); HoG_it != HoG.end(); HoG_it++)
				{
					*HoG_it /= sum_of_level;
				}
			}
			PHOG_descriptor.push_back(HoG);
			break;
		}
		case 1:
		{
			if (sum_of_level != 0.0)  //normalize the descriptor-entries
			{
				for (std::vector<float>::iterator HoG_it = HoG.begin(); HoG_it != HoG.end(); HoG_it++)
				{
					*HoG_it /= sum_of_level;
				}
			}
			PHOG_descriptor.push_back(HoG);
			break;
		}
		case 2:
		{
			one_collecting_vector.insert(one_collecting_vector.begin()+one_collecting_vector.size(), HoG.begin(), HoG.end());
			break;
		}
	}
	sum_of_all += sum_of_level;

	if (verbose) cerr << "PHOGFeature::calculate_PHOG_Pyramide -- Level 0 calculated, working on finer levels" << endl;
	if (verbose) cerr << "gradient_orientations.width(): " << gradient_orientations.width() << " gradient_orientations.height(): " << gradient_orientations.height() << endl;

	//further levels
	for (int level = 1; level < number_of_Levels; level++) 
	{
		if (verbose) cerr << "PHOGFeature::calculate_PHOG_Pyramide -- working on level "<< level << endl;
		if (like_AnnaBosch)
		{
			int step_x = (int) floor(gradient_orientations.width() / pow(2.0f,level) );
			int step_y = (int) floor(gradient_orientations.height() / pow(2.0f,level) );

			vector<float> PHoG_level;

			int run_y = 0;
			for (int y_counter = 0; y_counter < pow(2.0,level) ; y_counter++) 
			{
				int run_x = 0;
				for (int x_counter = 0; x_counter < pow(2.0,level) ; x_counter++)
				{
					vector<float> HoG_local (number_Of_Bins);
					float sum_of_hog(0.0);
	
					//check, wether rectangle lies on the boundary, if so, then correct the max-step
					int y_max = (run_y + step_y);
					if (gradient_orientations.height() < y_max)
						y_max = gradient_orientations.height();
	
					int x_max = (run_x + step_x);
					if (gradient_orientations.width() < x_max)
						x_max = gradient_orientations.width();
	
					for (int j = run_y; j < y_max; j++)
						for (int i = run_x; i < x_max; i++)
						{
							int orientation = 0;
							try{	orientation = gradient_orientations(i,j);
							}
							catch( ... )
							{
								cerr << "WARNING: PHOGFeature::calculate_PHOG_Pyramide gradient_orientations(i,j) not possible. (i,j): " << i << " " << j << endl;
							}
							float magnitude = 0.0;
							try{	magnitude = gradient_magnitudes(i,j);
							}
							catch( ... )
							{
								cerr << "WARNING: PHOGFeature::calculate_PHOG_Pyramide radient_magnitudes(i,j) not possible. (i,j): " << i << " " << j << endl;
							}
 							HoG_local[orientation] += magnitude;
							sum_of_hog += magnitude;
						}

					sum_of_level += sum_of_hog;
					
					switch(histrogram_concatenation)
					{
						case 0:
						{
							if (sum_of_hog != 0.0)  //normalize the descriptor-entries
							{
								for (std::vector<float>::iterator hog_it = HoG_local.begin(); hog_it != HoG_local.end(); hog_it++)
								{
									*hog_it /= sum_of_hog;
								}
							}
							PHOG_descriptor.push_back(HoG_local);
							break;
						}
						case 1:
						{
							for (std::vector<float>::const_iterator foo = HoG_local.begin(); foo != HoG_local.end(); foo++)
							{
								PHoG_level.insert(PHoG_level.begin()+PHoG_level.size(), HoG_local.begin(), HoG_local.end());
							}
							break;
						}
						case 2:
						{
								PHoG_level.insert(PHoG_level.begin()+PHoG_level.size(), HoG_local.begin(), HoG_local.end());
							break;
						}
					}
	
					run_x = run_x + step_x;
				}
				run_y = run_y + step_y;
			}
			
			sum_of_all += sum_of_level;
			
			switch(histrogram_concatenation)
			{
				case 0:
				{
					break;
				}
				case 1:
				{
					if (sum_of_level != 0.0)  //normalize the descriptor-entries
					{
						for (std::vector<float>::iterator Level_it = PHoG_level.begin(); Level_it != PHoG_level.end(); Level_it++)
						{
							*Level_it /= sum_of_level;
						}
					}
					PHOG_descriptor.push_back(PHoG_level);
					break;
				}
				case 2:
				{
					one_collecting_vector.insert(one_collecting_vector.begin()+one_collecting_vector.size(), PHoG_level.begin(), PHoG_level.end());
					break;
				}
			}
		}
		else //better than anna bosch
		{
			int step_x = (int) ceil(gradient_orientations.width() / pow(2.0f,level) );
			int step_y = (int) ceil(gradient_orientations.height() / pow(2.0f,level) );
			if (verbose) cerr << "step_x: " << step_x << " step_y: " << step_y << endl;

			std::vector<float> PHoG_level;
	
			int run_y = 0;
			for (int y_counter = 0; y_counter < pow(2.0f,level) ; y_counter++) 
			{
				int run_x = 0;
				if (verbose) cerr << "run_y: " << run_y << endl;
				for (int x_counter = 0; x_counter < pow(2.0f,level) ; x_counter++)
				{
					if (verbose) cerr << "run_x: " << run_x << endl;
					float sum_of_hog(0.0);
					vector<float> HoG_local (number_Of_Bins);
	
					//check, wether rectangle lies on the boundary, if so, then correct the max-step
					int y_max = (run_y + step_y);
					if (gradient_orientations.height() < y_max)
					{
						if (verbose) cerr << "y_max old:: " << y_max << " y_max_new: "<<gradient_orientations.height() << endl;
						y_max = gradient_orientations.height();
						
					}
	
					int x_max = (run_x + step_x);
					if (gradient_orientations.width() < x_max)
					{
						if (verbose) cerr << "x_max old:: " << x_max << " x_max_new: "<<gradient_orientations.width() << endl;
						x_max = gradient_orientations.width();
						
					}
			
					for (int j = run_y; j < y_max; j++)
						for (int i = run_x; i < x_max; i++)
						{
							int orientation = 0;
							try{	orientation = gradient_orientations.getPixel(i,j);
							}
							catch( ... )
							{
								cerr << "WARNING: PHOGFeature::calculate_PHOG_Pyramide gradient_orientations(i,j) not possible. (i,j): " << i << " " << j << endl;
							}
							float magnitude = 0.0;
							try{	magnitude = gradient_magnitudes.getPixel(i,j);
							}
							catch( ... )
							{
								cerr << "WARNING: PHOGFeature::calculate_PHOG_Pyramide gradient_magnitudes(i,j) not possible. (i,j): " << i << " " << j << endl;
							}
							if ( (orientation<0) || ((uint)orientation>=HoG_local.size()))
							{
								cerr << "orientation is " << orientation << " and does not fit to HoG_local.size(): " << HoG_local.size() << endl;
								cerr << "i: " << i << " j: " << j << " gradient_orientations.width() : " <<  gradient_orientations.width() << " gradient_orientations.height() : " << gradient_orientations.height() << endl;
							}
 							try{
								HoG_local[orientation] += magnitude;
							}
							catch( ... )
							{
								cerr << "WARNING: PHOGFeature::calculate_PHOG_Pyramide HoG_local[orientation] += magnitude not possible. orientation: " << orientation << " magnitude " << magnitude << endl;
							}
							sum_of_hog += magnitude;
						}
					sum_of_level += sum_of_hog;
					
					switch(histrogram_concatenation)
					{
						case 0:
						{
							if (sum_of_hog != 0.0)  //normalize the descriptor-entries
							{
								for (std::vector<float>::iterator hog_it = HoG_local.begin(); hog_it != HoG_local.end(); hog_it++)
								{
									*hog_it /= sum_of_hog;
								}
							}
							PHOG_descriptor.push_back(HoG_local);
							break;
						}
						case 1:
						{
							for (std::vector<float>::const_iterator foo = HoG_local.begin(); foo != HoG_local.end(); foo++)
							{
								PHoG_level.insert(PHoG_level.begin()+PHoG_level.size(), HoG_local.begin(), HoG_local.end());
							}
							break;
						}
						case 2:
						{
								PHoG_level.insert(PHoG_level.begin()+PHoG_level.size(), HoG_local.begin(), HoG_local.end());
							break;
						}
					}
	
					run_x = run_x + step_x;
				}
				run_y = run_y + step_y;
			}
			sum_of_all += sum_of_level;
			
			switch(histrogram_concatenation)
			{
				case 0:
				{
					break;
				}
				case 1:
				{
					if (sum_of_level != 0.0)  //normalize the descriptor-entries
					{
						for (std::vector<float>::iterator Level_it = PHoG_level.begin(); Level_it != PHoG_level.end(); Level_it++)
						{
							*Level_it /= sum_of_level;
						}
					}
					PHOG_descriptor.push_back(PHoG_level);
					break;
				}
				case 2:
				{
					one_collecting_vector.insert(one_collecting_vector.begin()+one_collecting_vector.size(), PHoG_level.begin(), PHoG_level.end());
					break;
				}
			}
		}
	}
	
	if (histrogram_concatenation == ALL)
	{
		if (sum_of_all != 0.0)  //normalize the descriptor-entries
		{
			for (std::vector<float>::iterator it = one_collecting_vector.begin(); it != one_collecting_vector.end(); it++)
			{
				*it /= sum_of_all;
			}
		}
		PHOG_descriptor.push_back(one_collecting_vector);
	}
}

/**
* @brief Calculates resulting PHOG-Features for the specified ROI in the given image
* @author Alexander Lütz
* @date 15/11/2011
*/
std::vector< std::vector<float> > PHOGFeature::calculate_PHOG_Features(const NICE::Image & orig_Image, const NICE::Rect & roi)
{
	if (like_AnnaBosch) //not supported in that version, 'cause !
	{
		std::cerr << "PHOGFeature::calculate_PHOG_Features is not supported right now" << std::endl;
// 		//Canny Edge Detector
// 		Image canny_Image;
// 		canny_Image = (*canny(orig_Image, 10,30) );
// 
// 		//gradient-calculation
// 		GrayImage16s* grad_x_Image= sobelX(canny_Image);
// 		GrayImage16s* grad_y_Image = sobelY(canny_Image);
// 		if (verbose)	cerr << "gradient-calculation done" << endl;
// 
// 		//gradient-orientation-calculation
// 		NICE::Image gradient_orientations;
// 		image_tool.calculateGradientOrientations( *grad_x_Image, *grad_y_Image, number_Of_Bins, gradient_orientations, unsignedBins);
// 		if (verbose)	cerr << "gradient-orientation-calculation done" << endl;
// 
// 		//gradient-magnitude-calculation
// 		//maybe this is not good - implicit cast from int to float in image structure
// 		NICE::Image* gradient_magnitudes_int = gradientStrength( (*grad_x_Image), (*grad_y_Image) );
// 		NICE::ImageT<float> gradient_magnitudes(orig_Image.width(), orig_Image.height());
// 		for (int y = 0; y < orig_Image.height(); y++)
// 			for (int x = 0; x < orig_Image.width(); x++)
// 			{
// 				gradient_magnitudes.setPixel(x,y,(*gradient_magnitudes_int).getPixel(x,y));
// 			}
// 		if (verbose)	cerr << "gradient-magnitude-calculation done" << endl;
// 		
// 		NICE::Image go_roi (gradient_orientations.subImage(roi));
// 		NICE::ImageT<float> gm_roi (gradient_magnitudes.subImage(roi));
// 
// 	//pyramide-calculation
// 
		std::vector< std::vector<float> > PHOG_pyramide;
// 		calculate_PHOG_Pyramide(go_roi, gm_roi, PHOG_pyramide);
// 
// 		if (verbose) cerr << "Pyramide-calculation done" << endl;

		return PHOG_pyramide;

	}
	else
	{
		//gradient-calculation
		NICE::ImageT<float> grad_x_Image;
		NICE::ImageT<float> grad_y_Image;
		image_tool.calculateGradients(orig_Image, grad_x_Image, grad_y_Image );
		if (verbose)	cerr << "gradient-calculation done" << endl;

		//gradient-orientation-calculation
		NICE::Image gradient_orientations;
		image_tool.calculateGradientOrientations(grad_x_Image, grad_y_Image, number_Of_Bins, gradient_orientations, unsignedBins);
		if (verbose) 	cerr << "gradient-orientation-calculation done" << endl;

		//gradient-magnitude-calculation
		NICE::ImageT<float> gradient_magnitudes;
		image_tool.calculateGradientMagnitudes(grad_x_Image, grad_y_Image, gradient_magnitudes);
		if (verbose) 	cerr << "gradient-magnitude-calculation done" << endl;

		NICE::Image go_roi (gradient_orientations.subImage(roi));
		NICE::ImageT<float> gm_roi (gradient_magnitudes.subImage(roi));

	//pyramide-calculation

		std::vector< std::vector<float> > PHOG_pyramide;
		calculate_PHOG_Pyramide(go_roi, gm_roi, PHOG_pyramide);

		if (verbose) cerr << "Pyramide-calculation done" << endl;

		return PHOG_pyramide;
	}
}
//TODO ebenso für Farbbilder, falls das erwünscht ist. Frau Bosch macht einfach nur eine Grauwertkonvertierunt, also auch nicht so schön, wie Dalal und Triggs.!


/** public things*/

/** 
* @brief Simple Default Constructor 
* @author Alexander Lütz
* @date 15/11/2011
*/
PHOGFeature::PHOGFeature()
{
	image_tool = OBJREC::Image_tools();
	number_Of_Bins = 9;
	unsignedBins = true;
	number_of_Levels = 3;
	like_AnnaBosch = false;
	distances_only_between_levels = true;
	histrogram_concatenation = NONE;
	verbose = false;
}

/** 
* @brief Recommended Constructor 
* @author Alexander Lütz
* @date 15/11/2011
*/
PHOGFeature::PHOGFeature( const Config *conf, std::string section)
{
	image_tool = OBJREC::Image_tools();
	number_Of_Bins = conf->gI("PHOGFeature", "number_Of_Bins", 9);
	unsignedBins = conf->gB("PHOGFeature", "unsignedBins", true);
	number_of_Levels = conf->gI("PHOGFeature", "number_of_Levels", 3);
	like_AnnaBosch = conf->gB("PHOGFeature", "like_AnnaBosch", false);
	distances_only_between_levels = conf->gB("PHOGFeature", "distances_only_between_levels", true);
	switch(conf->gI("PHOGFeature", "histrogram_concatenation", 0) )
	{
		case 0:
		{histrogram_concatenation = NONE; break;}
		case 1:
		{histrogram_concatenation = LEVELWISE; break;}
		case 2:
		{histrogram_concatenation = ALL; break;}
	}
	verbose = conf->gB("PHOGFeature", "verbose", false);
}

/** 
* @brief Simple Destructor 
* @author Alexander Lütz
* @date 15/11/2011
*/
PHOGFeature::~PHOGFeature()
{

}


/** 
* @brief Creating the PHOG-featureVectores of all trainingexamples
* @author Alexander Lütz
* @date 15/11/2011
*/
// std::vector<std::vector< std::vector<float> > >  PHOGFeature::createAllFeatureVectors(const OBJREC::LabeledSet::Permutation & order)
// {
// 
// 	std::vector<std::vector< std::vector<float> > > PHOG_Features_all_images;
// 
// 	ProgressBar pb_createFV ("PHOGFeature::createAllFeatureVectors");
// 	pb_createFV.show();
// 
// 	uint k = 0;
// 	for ( LabeledSet::Permutation::const_iterator i = order.begin(); i != order.end(); i++,k++  )
// 	{
// 		string imgfilename = (*i).second->img();
// 
// 		NICE::Image img(imgfilename);
// 
// 		NICE::Rect roi = NICE::Rect(0,0,img.width(),img.height());
// 		vector<vector<float> > PHOG = calculate_PHOG_Features(img, roi);
// 
// 		PHOG_Features_all_images.push_back ( PHOG );
// 
// 		pb_createFV.update ( order.size() );
// 	}
// 
// 	// hide the last progress bar
// 	pb_createFV.hide();
// 
// 	return PHOG_Features_all_images;
// }


/** 
* @brief Creating the PHOG-featureVectores of all trainingexamples
* @author Alexander Lütz
* @date 15/11/2011
*/
// std::vector<std::vector< std::vector<float> > >  PHOGFeature::createAllFeatureVectors(const OBJREC::LabeledSet::Permutation & order, std::vector< NICE::Image > & gradient_orientations, std::vector<NICE::ImageT<float> > & gradient_magnitudes)
// {
// 
// 	std::vector<std::vector< std::vector<float> > > PHOG_Features_all_images;
// 
// 	cerr << "Calculating gradient orientations." << endl;
// 	gradient_orientations = calculate_gradient_orientations(order);
// 	cerr << "Calculating gradient magnitudes." << endl;
// 	gradient_magnitudes = calculate_gradient_magnitudes(order);
// 
// 	ProgressBar pb_quantization ("PHOGFeature::createAllFeatureVectors");
// 	pb_quantization.show();
// 
// 	uint k = 0;
// 	for ( LabeledSet::Permutation::const_iterator i = order.begin(); i != order.end(); i++,k++  )
// 	{
// 		std::string imgfilename = (*i).second->img();
// 
// 		NICE::Image img(imgfilename);
// 
// 		std::vector<std::vector<float> > PHOG;
// 		calculate_PHOG_Pyramide(gradient_orientations[k], gradient_magnitudes[k], PHOG);
// 
// 		PHOG_Features_all_images.push_back ( PHOG );
// 
// 		pb_quantization.update ( order.size() );
// 	}
// 
// 	// hide the last progress bar
// 	pb_quantization.hide();
// 
// 	return PHOG_Features_all_images;
// }

/** 
* @brief Creating the PHOG-featureVectores of all trainingexamples
* @author Alexander Lütz
* @date 15/11/2011
*/
// // // std::vector<std::vector< std::vector<float> > >  PHOGFeature::createAllFeatureVectors(const OBJREC::LabeledSet::Permutation & order, const std::vector<int> & trainSelection)
// // // {
// // // 
// // // 	std::vector<std::vector< std::vector<float> > > PHOG_Features_all_images;
// // // 
// // // 	ProgressBar pb_quantization ("PHOGFeature::createAllFeatureVectors");
// // // 	pb_quantization.show();
// // // 
// // // 	uint k = 0;
// // // 	for ( std::vector<int>::const_iterator i = trainSelection.begin(); i != trainSelection.end(); i++,k++ )
// // // 	{
// // // 		if (verbose) cerr << " Image number " << *i << " will be treated now" << endl;
// // // 		string imgfilename = order[*i].second->img();
// // // 
// // // 		NICE::Image img(imgfilename);
// // // 
// // // 		NICE::Rect roi = NICE::Rect(0,0,img.width(),img.height());
// // // 		vector<vector<float> > PHOG = calculate_PHOG_Features(img, roi);
// // // 
// // // 		PHOG_Features_all_images.push_back ( PHOG );
// // // 
// // // 		pb_quantization.update ( trainSelection.size() );
// // // 	}
// // // 
// // // 	// hide the last progress bar
// // // 	pb_quantization.hide();
// // // 
// // // 	return PHOG_Features_all_images;
// // // }
// // 
// // 
// // 
/** 
* @brief Creating the PHOG-featureVectore for one trainingexample
* @author Alexander Lütz
* @date 15/11/2011
*/
std::vector<std::vector<float> > PHOGFeature::createOneFeatureVector(const std::string & imgfilename, const NICE::Rect & ROI)
{
	NICE::Image img(imgfilename);

	std::vector<std::vector<float> > PHOG (calculate_PHOG_Features(img, ROI));

	return PHOG;
}

/** 
* @brief Creating the PHOG-featureVectore for one trainingexample
* @author Alexander Lütz
* @date 15/11/2011
*/
std::vector<std::vector<float> > PHOGFeature::createOneFeatureVector(const std::string & imgfilename)
{
	NICE::Image img(imgfilename);
	NICE::Rect ROI(0,0,img.width(), img.height());

	std::vector<std::vector<float> > PHOG (calculate_PHOG_Features(img, ROI));

	return PHOG;
}

/** 
* @brief Creating the PHOG-featureVectore for one trainingexample
* @author Alexander Lütz
* @date 15/11/2011
*/
std::vector<std::vector<float> > PHOGFeature::createOneFeatureVector(const NICE::Image img, const NICE::Rect & ROI)
{
	std::vector<std::vector<float> > PHOG (calculate_PHOG_Features(img, ROI));

	return PHOG;
}

/** 
* @brief Creating the PHOG-featureVectore for one trainingexample
* @author Alexander Lütz
* @date 15/11/2011
*/
std::vector<std::vector<float> > PHOGFeature::createOneFeatureVector(const NICE::Image img)
{
	NICE::Rect ROI(0,0,img.width(), img.height());
	std::vector<std::vector<float> > PHOG (calculate_PHOG_Features(img, ROI));

	return PHOG;
}

/** 
* @brief computes the featurevector for the given image, which is already converted to a gradient-image, just considering features in the specified ROI
* @author Alexander Lütz
* @date 15/11/2011
*/
std::vector< std::vector<float> > PHOGFeature::createOneFeatureVectorDirect(NICE::Image & gradient_orientations, NICE::ImageT<float> & gradient_magnitudes, const NICE::Rect & ROI)
{
	NICE::Image ROI_go (gradient_orientations.subImage(ROI));
	NICE::ImageT<float> ROI_gm (gradient_magnitudes.subImage(ROI));

	std::vector< std::vector<float> > PHOG_pyramide;
	calculate_PHOG_Pyramide(ROI_go, ROI_gm, PHOG_pyramide);

	return PHOG_pyramide;
}

/** 
* @brief computes the featurevector for the given image, which is already converted to a gradient-image, considering the whole image
* @author Alexander Lütz
* @date 15/11/2011
*/
std::vector< std::vector<float> > PHOGFeature::createOneFeatureVectorDirect(NICE::Image & gradient_orientations, NICE::ImageT<float> & gradient_magnitudes)
{
	NICE::Image ROI_go (gradient_orientations);
	NICE::ImageT<float> ROI_gm (gradient_magnitudes);

	std::vector< std::vector<float> > PHOG_pyramide;
	calculate_PHOG_Pyramide(ROI_go, ROI_gm, PHOG_pyramide );

	return PHOG_pyramide;
}
// // 
// // /** 
// // * @brief computes the gradient-orientation-images of all training-images
// // * @author Alexander Lütz
// // * @date 15/11/2011
// // */
// // std::vector< NICE::Image> PHOGFeature::calculate_gradient_orientations(const OBJREC::LabeledSet::Permutation & order)
// // {
// // 	std::vector< NICE::Image> gradient_orientations;
// // 
// // 	for(OBJREC::LabeledSet::Permutation::const_iterator i = order.begin(); i != order.end(); i++)
// // 	{
// // 		string filename = (*i).second->img();
// // 		NICE::Image img (filename);
// // 		//gradient-calculation
// // 		NICE::ImageT<float> grad_x_Image;
// // 		NICE::ImageT<float> grad_y_Image;
// // 		image_tool.calculateGradients(img, grad_x_Image, grad_y_Image );
// // 	
// // 		//gradient-orientation-calculation
// // 		NICE::Image gradient_orientation_image;
// // 		image_tool.calculateGradientOrientations(grad_x_Image, grad_y_Image, number_Of_Bins, gradient_orientation_image, unsignedBins);
// // 
// // 		gradient_orientations.push_back(gradient_orientation_image);
// // 	}
// // 
// // 	return gradient_orientations;
// // }
// 
// /** 
// * @brief computes the gradient-magnitudes-images of all training-images
// * @author Alexander Lütz
// * @date 15/11/2011
// */
// std::vector< NICE::ImageT<float> > PHOGFeature::calculate_gradient_magnitudes(const OBJREC::LabeledSet::Permutation & order)
// {
// 	std::vector< NICE::ImageT<float> > gradient_magnitudes;
// 
// 	for(OBJREC::LabeledSet::Permutation::const_iterator i = order.begin(); i != order.end(); i++)
// 	{
// 		string filename = (*i).second->img();
// 		Image img (filename);
// 		//gradient-calculation
// 		NICE::ImageT<float> grad_x_Image;
// 		NICE::ImageT<float> grad_y_Image;
// 		image_tool.calculateGradients(img, grad_x_Image, grad_y_Image );
// 	
// 		//gradient-orientation-calculation
// 		NICE::ImageT<float> gradient_magnitude_image;
// 		image_tool.calculateGradientMagnitudes(grad_x_Image, grad_y_Image, gradient_magnitude_image);
// 
// 		gradient_magnitudes.push_back(gradient_magnitude_image);
// 	}
// 
// 	return gradient_magnitudes;
// }

/** 
* @brief computes the gradient-orientation-images of all training-images
* @author Alexander Lütz
* @date 15/11/2011
*/
NICE::Image PHOGFeature::calculate_gradient_orientations(const std::string & imgfilenam)
{
	NICE::Image gradient_orientations;

	NICE::Image img (imgfilenam);
	//gradient-calculation
	NICE::ImageT<float> grad_x_Image;
	NICE::ImageT<float> grad_y_Image;
	image_tool.calculateGradients(img, grad_x_Image, grad_y_Image );

	//gradient-orientation-calculation
	NICE::Image gradient_orientation_image;
	image_tool.calculateGradientOrientations(grad_x_Image, grad_y_Image, number_Of_Bins, gradient_orientation_image, unsignedBins);

	return gradient_orientations;
}

/** 
* @brief computes the gradient-magnitudes-images of all training-images
* @author Alexander Lütz
* @date 15/11/2011
*/
NICE::ImageT<float> PHOGFeature::calculate_gradient_magnitudes(const std::string & imgfilename)
{
	NICE::ImageT<float> gradient_magnitudes;

	Image img (imgfilename);
	//gradient-calculation
	NICE::ImageT<float> grad_x_Image;
	NICE::ImageT<float> grad_y_Image;
	image_tool.calculateGradients(img, grad_x_Image, grad_y_Image );

	//gradient-orientation-calculation
	NICE::ImageT<float> gradient_magnitude_image;
	image_tool.calculateGradientMagnitudes(grad_x_Image, grad_y_Image, gradient_magnitude_image);

	return gradient_magnitudes;
}

/** 
* @brief Compute the resulting kernel measuring the distance between the given feature-vectores
* @author Alexander Lütz
* @date 15/11/2011
*/
void PHOGFeature::calculate_Kernel_from_Features(const std::vector<std::vector< std::vector<float> > > & PHoG_Features, NICE::Matrix & PHoG_Kernel){

// 	ProgressBar pb_kernelcalc ("PHOGFeature::Kernel Calculation");
// 	pb_kernelcalc.show();
	PHoG_Kernel = NICE::Matrix(PHoG_Features.size(), PHoG_Features.size(), 0.0);
	uint ik = 0;
	for ( std::vector< std::vector < std::vector<float> > >::const_iterator i = PHoG_Features.begin();i != PHoG_Features.end(); i++,ik++ )
	{
		uint jk = ik;
		for ( std::vector< std::vector< std::vector<float> > >::const_iterator j = i; 
			j != PHoG_Features.end(); j++,jk++ )
		{
			double kernelValue (measureDistance(*i,*j));
		
			PHoG_Kernel(ik,jk) = kernelValue;
			PHoG_Kernel(jk,ik) = kernelValue;
		}
// 		pb_kernelcalc.update ( PHoG_Features.size() );
	}
}

/** 
* @brief function which computes the exp^(-Chi^2)-kernel of two PHOG-feature-vectores a and b
* @author Alexander Lütz
* @date 15/11/2011
*/
double PHOGFeature::measureDistance ( const std::vector<std::vector<float> > & a, const std::vector<std::vector<float> > & b )
{
	double expChi_value = 0.0;

	if (a.size() != b.size() ) {
		cerr << "a.size(): " << a.size() << " and b.size(): " << b.size() << endl;
		fthrow(IOException, "Sizes of PHOG-Feature-vectores do not fit!");
	}

	for (uint i = 0; i < a.size(); i++)  //run over every HoG-Level 
	{
		std::vector<float> a_intern = a[i];
		std::vector<float> b_intern = b[i];

		double chi_value = 0.0;

		if (a_intern.size() != b_intern.size() )  {
			cerr << "a_intern.size(): " << a_intern.size() << " and b_intern.size(): " << b_intern.size() << endl;
			fthrow(IOException, "Sizes of PHOG-Feature-vectores do not fit!");
		}

		for (uint j = 0; j < a_intern.size(); j++) //run over every HoG-entry of this level
		{
			float u = a_intern[j];
			float v = b_intern[j];
			float s = ( u + v );
			if ( fabs(s) < 10e-6 ) continue;
			float d = u-v;
			chi_value += d*d / s;
		}

		chi_value *= 0.5;
		expChi_value += exp(-chi_value);
	}
	expChi_value /= a.size(); //normalize to be in between zero and one

	return expChi_value;
}

/** 
* @brief Simply set the verbose-flag
* @author Alexander Lütz
* @date 15/11/2011
*/
void PHOGFeature::set_verbose(const bool & new_verbose){
	verbose = new_verbose;
}