/**
* @file Image_tools.h
* @author Alexander Freytag
* @date 18/11/2010
* @brief Contains tools for Image_Processing
*/
#ifndef _NICE_OBJREC_IMAGETOOLS
#define _NICE_OBJREC_IMAGETOOLS

#include "core/image/ImageT.h"
#include "core/image/ColorImageT.h"
#include <utility>

namespace OBJREC {
class Image_tools
{

    protected:

    public:

	/** simple constructor */
	Image_tools();

	/** simple destructor */
	~Image_tools();

	/**
         * @author Alexander Freytag
         * @brief Calculate gradient-images for x- and y-direction, using [1 0 -1] without smoothing
         */
	void calculateGradients(
            const NICE::Image & origImage,
            NICE::ImageT<float> & grad_x_Image,
            NICE::ImageT<float> & grad_y_Image );

	/**
         * @author Alexander Freytag
         * @brief Calculate gradient-images for x- and y-direction, using [1 0 -1] without smoothing, considering the chanel with the greatest magnitude als resulting gradient
         */
	void calculateGradients(
            NICE::ColorImage origColorImage,
            NICE::ImageT<float> & grad_x_Image,
            NICE::ImageT<float> & grad_y_Image );

	/**
         * @author Alexander Freytag
         * @brief Calculate gradient-orientations
         */
	void calculateGradientOrientations(
            const NICE::ImageT<float> & grad_x_Image,
            const NICE::ImageT<float> & grad_y_Image,
            const int & number_Of_Bins,
            NICE::Image & gradient_orientations,
            const bool unsignedBins=true );

	void calculateGradientOrientations(
            const NICE::GrayImage16s & grad_x_Image,
            const NICE::GrayImage16s & grad_y_Image,
            const int & number_Of_Bins,
            NICE::Image & gradient_orientations,
            const bool unsignedBins=true );

	/**
          *@author Alexander Freytag
          *@brief Calculate gradient-magnitudes
          */
	void calculateGradientMagnitudes(
            const NICE::ImageT<float> & grad_x_Image,
            const NICE::ImageT<float> & grad_y_Image,
            NICE::ImageT<float> & gradient_magnitudes );

	/**
          *@author Alexander Freytag
          *@brief Normalizes the descriptor-vector of the specified block, using L2-norm
          */
	std::vector<float> normalizeBlockDescriptor(
            const std::vector<float> & orig_Block_Descriptor,
            const float epsilon = 0.01 );

	/**
          *author Alexander Freytag
          *@brief Calculates the resulting HoG-Features for an image by normalizing spatial blocks und storing the resulting normalized histograms in a vector - not implemented up to now
          */
	std::vector< std::vector<float> > calculateResultingHogFeatures(
            const NICE::Image & gradient_orientations,
            const NICE::ImageT<float> & gradient_magnitudes,
            const int & blocksize = 2,
            const int & cellsize = 8 );
};
}

#endif