NICE_VisLearning/features/localfeatures/LocalFeatureSift.h

/**
* @file LocalFeatureSift.h
* @brief local feature with sift
* @author Erik Rodner
* @date 03/10/2012 (Eric Bach)
* @note some notes to the use of siftGPU (added by Eric Bach)
*		- install cudaSift & siftGPU (see Makefile.config)
*		- add to libdepend.inc: $(call PKG_DEPEND_EXT, CUDASIFT) to specify: -DNICE_USELIB_CUDASIFT as compilerflag
*		- add to section [LFSiftPP] use_siftgpu=true (or 'false' to disable the gpu-support)
*		
*		If you use the gpu-support just one device is supported until now.
*		If your device do not support the siftGPU completly the class switch to "normal" sift.
*		It is possible to compile this class without siftGPU, but then you must not specify the flag: -DNICE_USELIB_CUDASIFT.
*/
#ifndef LOCALFEATURESIFTINCLUDE
#define LOCALFEATURESIFTINCLUDE

// NICE includes
#include <objrec/baselib/StringTools.h>
#include <objrec/baselib/Config.h>
#include "LocalFeature.h"
#include "sift.h"

// std includes
#include <iostream>
#include <string>
#include <stdexcept>

// SiftGPU & GL
#ifdef NICE_USELIB_CUDASIFT
		#include <src/SiftGPU.h>
		#include <GL/gl.h>
#endif


namespace OBJREC {

/** local feature with sift */
class LocalFeatureSift : public LocalFeature
{
private:
    const Config* conf;

protected:
    int octaves;
    int levels;
    bool normalizeFeature;
    int first_octave;
    double magnif;
    bool deletemode;
    bool integerValues;

    // for SiftGPU
    bool usegpu;

    float threshold;
    float edgeThreshold;

    void withPP( const NICE::Image & img, VVector & positions, VVector & descriptors ) const;
#ifdef NICE_USELIB_CUDASIFT
    void withGPU( const NICE::Image & img, VVector & positions, VVector & descriptors ) const;
#endif

public:

    /** simple constructor */
    LocalFeatureSift ( const Config *conf );

    /** simple destructor */

    virtual ~LocalFeatureSift();

    /**
     * returns the size of each the SIFT-Feature
     * @return 128
     */
    int getDescSize() const {
        return 128;
    };


    //! returns true if gpu is used
    bool isGpuUsed() const {
#ifdef NICE_USELIB_CUDASIFT
        return usegpu;
#else
		return false;
#endif
    };

    /**
     * get the descriptor
     * @param img input image
     * @param positions positions for the SIFT features
     * @param descriptors output
     * @return 0
     */
    virtual int getDescriptors ( const NICE::Image & img,
                                 VVector & positions,
                                 VVector & descriptors ) const;

    /**
     * computes the descriptor for a single image
     * @param img
     * @param positions
     * @param descriptors
     */
    void computeDesc( const NICE::Image & img, VVector & positions, VVector & descriptors ) const;

    /**
     * sort positions by scales for faster computing of the Keypoint orientation
     * @param positions
     */
    void sortPositions(VVector & positions) const;

    void visualizeFeatures ( NICE::Image & mark, const VVector & positions, size_t color ) const;




};


} // namespace

#endif