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improving background subtraction

Hi, I am working on video processing project to detect fore ground objects. Below is a part of my code which is used to separate foreground and background.

#include "opencv2/core/core.hpp"
#include "opencv2/video/background_segm.hpp"
#include "opencv2/highgui/highgui.hpp"
#include <stdio.h>

using namespace std;
using namespace cv;

//this is a sample for foreground detection functions
int main(int argc, const char** argv)

    VideoCapture cap;
    bool update_bg_model = true;;

    if( !cap.isOpened() )
        printf("can not open camera or video file\n");
        return -1;

    namedWindow("image", CV_WINDOW_NORMAL);
    namedWindow("foreground mask", CV_WINDOW_NORMAL);
    namedWindow("foreground image", CV_WINDOW_NORMAL);
    namedWindow("mean background image", CV_WINDOW_NORMAL);

    BackgroundSubtractorMOG2 bg_model;
    Mat img, fgmask, fgimg;

        cap >> img;

        if( img.empty() )

        if( fgimg.empty() )
          fgimg.create(img.size(), img.type());

        //update the model
        bg_model(img, fgmask, update_bg_model ? -1 : 0);

        fgimg = Scalar::all(0);
        img.copyTo(fgimg, fgmask);

        Mat bgimg;

        imshow("image", img);
        imshow("foreground mask", fgmask);
        imshow("foreground image", fgimg);
          imshow("mean background image", bgimg );

        char k = (char)waitKey(30);
        if( k == 27 ) break;
        if( k == ' ' )
            update_bg_model = !update_bg_model;
                printf("Background update is on\n");
                printf("Background update is off\n");

    return 0;

In the foreground mask window I am getting lot of noise along with the actual fore ground object. Also the fulll object is note recognized as foreground. I need to bound the fore ground objects with rectangles as well. Wil BoundRect() do the job if I draw contours around in the foreground mask?...Also what are the most recommended parameter to be passed while finding contours(findcontour()) and for the BoundRect function...thanks in advance