optflow.cpp

#include "optflow.h"
#include "ui_optflow.h"



OptFlow::OptFlow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::OptFlow)
{
    needToInit = false;
    plot_datas.resize(2);
    termcrit = TermCriteria(CV_TERMCRIT_ITER|CV_TERMCRIT_EPS, 20, 0.03);
    cap = new capture_webcam(this);
    main_timer = new QTimer(this);
    connect(main_timer,SIGNAL(timeout()),this,SLOT(timerEvent()));


    main_timer->start(2);
}

void OptFlow::timerEvent()
{
    cap->frame.copyTo(colorframe);
    cvtColor(colorframe, grayframe, CV_BGR2GRAY);
    OptFlow_LK();
}

void OptFlow::OptFlow_LK()
{

    if( needToInit )
    {
        goodFeaturesToTrack(grayframe, points[1], MAX_COUNT, 0.01, 10, Mat(), 3, 0, 0.04);
        cornerSubPix(grayframe, points[1], subPixWinSize, Size(-1,-1), termcrit);
    }
    else if( !points[0].empty() )
    {
        vector<uchar> status;
        vector<float> err;
        if(prevGray.empty())
            grayframe.copyTo(prevGray);
        calcOpticalFlowPyrLK(prevGray, grayframe, points[0], points[1], status, err, winSize,
                             3, termcrit, 0, 0.001);



        Features_counter =0;

        for( size_t i = 0 ; i < points[1].size(); i++ )
        {
            if( status[i] )
            {
                points[1][Features_counter++] = points[1][i];
                line(colorframe, points[0][i], points[1][i], Scalar(0,255,0), 1, 8, 0);
                Point2f p1 = points[0][i], p2 = points[1][i];
                delta_x += (p1.x - p2.x);
                delta_y += (p1.y - p2.y);
            }
        }
        delta_x /= Features_counter;
        delta_y /= Features_counter;
        points[1].resize(Features_counter);
        qDebug() << (int)delta_x << " , "<<(int)delta_y;
    }
#ifdef _GRAPH
    plot_datas[0] = delta_x;
    plot_datas[1] = delta_y;

    plot1.Plot("X(t)-Y(t) Velocity", -100, 100, plot_datas);
#endif

    if(points[1].size() < (unsigned int)THRESH_REFRESH)
        needToInit = true;
    else
        needToInit = false;

#ifdef _GRAPH
    imshow("LK Demo", colorframe);
#endif

    waitKey(1);

    std::swap(points[1], points[0]);
    cv::swap(prevGray, grayframe);
}





OptFlow::~OptFlow()
{
//    delete ui;
}