[Tutorial] Adding new Tracker Method for dummies

/*---------------STEP 1---------------------*/
/* modify this file
*  opencv2/tracking/tracker.hpp
*  and put several lines of snippet similar to 
*  the following:
*/ 
/*------------------------------------------*/

class CV_EXPORTS_W TrackerKCF : public Tracker
{
 public:
  struct CV_EXPORTS Params
  {
    Params();
    void read( const FileNode& /*fn*/ );
    void write( FileStorage& /*fs*/ ) const;
  };

  /** @brief Constructor
    @param parameters KCF parameters TrackerKCF::Params
     */
  BOILERPLATE_CODE("KCF",TrackerKCF);
};


/*---------------STEP 2---------------------*/
/* modify this file
*  src/tracker.cpp
*  add one line in function  
*  Ptr<Tracker> Tracker::create( const String& trackerType )
*/ 
/*------------------------------------------*/

Ptr<Tracker> Tracker::create( const String& trackerType )
{
  BOILERPLATE_CODE("MIL",TrackerMIL);
  BOILERPLATE_CODE("BOOSTING",TrackerBoosting);
  BOILERPLATE_CODE("MEDIANFLOW",TrackerMedianFlow);
  BOILERPLATE_CODE("TLD",TrackerTLD);
  BOILERPLATE_CODE("KCF",TrackerKCF); // add this line!
  return Ptr<Tracker>();
}


/*---------------STEP 3---------------------*/
/* make a new file and paste the snippet below
*  and modify it according to your needs.
*  also make sure to put the LICENSE part.
*  src/trackerKCF.cpp
*/
/*------------------------------------------*/

/*---------------------------
|  TrackerKCFModel
|---------------------------*/
namespace cv{
   /**
  * \brief Implementation of TrackerModel for MIL algorithm
  */
  class TrackerKCFModel : public TrackerModel{
  public:
    TrackerKCFModel(TrackerKCF::Params /*params*/){}
    ~TrackerKCFModel(){}
  protected:
    void modelEstimationImpl( const std::vector<Mat>& responses ){}
    void modelUpdateImpl(){}
  };
} /* namespace cv */


/*---------------------------
|  TrackerKCF
|---------------------------*/
namespace cv{
  
  /*
 * Prototype
 */
  class TrackerKCFImpl : public TrackerKCF{
  public:
    TrackerKCFImpl( const TrackerKCF::Params &parameters = TrackerKCF::Params() );
    void read( const FileNode& fn );
    void write( FileStorage& fs ) const;
  
  protected:
    bool initImpl( const Mat& image, const Rect2d& boundingBox );
    bool updateImpl( const Mat& image, Rect2d& boundingBox );
    
    TrackerKCF::Params params;
  };
    
  /*
 * Constructor
 */
  Ptr<TrackerKCF> TrackerKCF::createTracker(const TrackerKCF::Params &parameters){
      return Ptr<TrackerKCFImpl>(new TrackerKCFImpl(parameters));
  }
  TrackerKCFImpl::TrackerKCFImpl( const TrackerKCF::Params &parameters ) :
      params( parameters )
  {
    isInit = false;
  }
  
  void TrackerKCFImpl::read( const cv::FileNode& fn ){
    params.read( fn );
  }

  void TrackerKCFImpl::write( cv::FileStorage& fs ) const{
    params.write( fs );
  }
  
  
  bool TrackerKCFImpl::initImpl( const Mat& image, const Rect2d& boundingBox ){
    model=Ptr<TrackerKCFModel>(new TrackerKCFModel(params));
    return true;
  }
  bool TrackerKCFImpl::updateImpl( const Mat& image, Rect2d& boundingBox ){return true;}
  
  /*
 * Parameters
 */
  TrackerKCF::Params::Params(){
      
  }

  void TrackerKCF::Params::read( const cv::FileNode& fn ){
    
  }

  void TrackerKCF::Params::write( cv::FileStorage& fs ) const{
    
  }
  
} /* namespace cv */