opencv/samples/cpp/bgfg_segm.cpp

#include <opencv2/video/background_segm.hpp>
#include <opencv2/highgui/highgui.hpp>

#include <stdio.h>
void help()
{
 printf("\nDo background segmentation, especially demonstrating the use of cvUpdateBGStatModel.\n"
"Learns the background at the start and then segments.\n"
"Learning is togged by the space key. Will read from file or camera\n"
"Call:\n"
"./  bgfg_segm [file name -- if no name, read from camera]\n\n");
}

//this is a sample for foreground detection functions
int main(int argc, char** argv)
{
    IplImage*       tmp_frame = NULL;
    CvCapture*      cap = NULL;
    bool update_bg_model = true;

    if( argc < 2 )
        cap = cvCaptureFromCAM(0);
    else
        cap = cvCaptureFromFile(argv[1]);
    help();
    
    if( !cap )
    {
        printf("can not open camera or video file\n");
        return -1;
    }
    
    tmp_frame = cvQueryFrame(cap);
    if(!tmp_frame)
    {
        printf("can not read data from the video source\n");
        return -1;
    }

    cvNamedWindow("BG", 1);
    cvNamedWindow("FG", 1);

    CvBGStatModel* bg_model = 0;
    
    for( int fr = 1;tmp_frame; tmp_frame = cvQueryFrame(cap), fr++ )
    {
        if(!bg_model)
        {
            //create BG model
            bg_model = cvCreateGaussianBGModel( tmp_frame );
            //bg_model = cvCreateFGDStatModel( temp );
            continue;
        }
        
        double t = (double)cvGetTickCount();
        cvUpdateBGStatModel( tmp_frame, bg_model, update_bg_model ? -1 : 0 );
        t = (double)cvGetTickCount() - t;
        printf( "%d. %.1f\n", fr, t/(cvGetTickFrequency()*1000.) );
        cvShowImage("BG", bg_model->background);
        cvShowImage("FG", bg_model->foreground);
        char k = cvWaitKey(5);
        if( k == 27 ) break;
        if( k == ' ' )
        {
            update_bg_model = !update_bg_model;
            if(update_bg_model)
            	printf("Background update is on\n");
            else
            	printf("Background update is off\n");
        }
    }


    cvReleaseBGStatModel( &bg_model );
    cvReleaseCapture(&cap);

    return 0;
}