PCA.h

#ifndef MTF_PCA_H
#define MTF_PCA_H

#include "SSDBase.h"

_MTF_BEGIN_NAMESPACE

struct PCAParams : AMParams{
    int n_eigenvec;
    int batch_size;
    double f_factor;
    bool show_basis;
    PCAParams(const AMParams *am_params,
        int _n_eigenvec,
        int _batch_size,
        double _f_factor,
        bool _show_basis);
    PCAParams(const PCAParams *params = nullptr);
};

class PCA : public SSDBase{
public:

    typedef PCAParams ParamType;

    PCA(const ParamType *pca_params = nullptr, const int _n_channels = 1);

    // Returns a normalized version of the similarity that lies between 0 and 1
    double getLikelihood() const override;

    // Initialize the features
    void initializeSimilarity() override;

    // Update the similarity
    void updateSimilarity(bool prereq_only = true) override;
    void updateModel(const Matrix2Xd& curr_pts) override;

    // Defined in Appearance Model,
    // It is called before performing the first iteration on a new image
    // to indicate that the image has changed since the last time the
    // update functions were called
    void setFirstIter() override;

    // It is called after performing the last iteration on a new image
    void clearFirstIter() override;

protected:

    ParamType params;

    // *****************************
    MatrixXd addi_patches;
    VectorXd mean_prev_patches;
    VectorXd max_patch_eachframe;
    int n_prev_patches;
    unsigned int batch_size;

    MatrixXd U;
    VectorXd sigma;
    bool U_available;

    int cv_img_type_uchar, cv_img_type_float;

    // update the basis U and eigen values sigma
    void updateBasis();

    // One step of incremental PCA
    void incrementalPCA();

    // the core algorithm in ivt tracker:
    // sklm(Sequential Karhunen-Loeve Transform with Mean update)
    void sklm(MatrixXd &U, VectorXd &sigma, VectorXd &mu_A, 
        MatrixXd &B, int &n, double ff, int max_n_eig);

    // display the basis and the reconstructed image
    void display_images(const VectorXd &curr_image,
        const VectorXdM &error_image);
    void display_basis();

};

_MTF_END_NAMESPACE

#endif