frame difference method[background subtraction]

Question

i m trying to implement frame difference method for performing background subtraction. The problem is when i try to show frame difference in a window. I dun get any output[black window].This is the code implemented

#include <highgui.h>
#include <iostream>
using namespace cv;

int main()
{

    VideoCapture cap("Camouflage/b%05d.bmp");
    if(!cap.isOpened())
    {
        std::cout<<"failed to open image sequence";
        return 1;
    }
    char c;
    Mat frame1, frame2, frame3;
    namedWindow("Original Frames",1);   
    namedWindow("Frame Difference",1);
    while(1)
    {
        cap>>frame1;
        if(frame1.empty())
        {
            std::cout<<"Frame1Message->End of sequence"<<std::endl;
            break;
        }
        cap>>frame2;
        if(frame2.empty())
        {
            std::cout<<"Frame2Message->End of sequence"<<std::endl;
            break;
        }
        //  absdiff(frame1,frame2,frame3);

        frame3=frame1.clone();
        frame3=frame3-frame2;
        //imwrite("C:/Users/hp/Desktop/file
        imshow("Frame Difference",frame3);
        c=waitKey(90);
        if(c==27)
            break;

        imshow("Original Frames",frame1);
        c=waitKey(90);
        if(c==27)           
            break;
    }
}

can anyone help me out ?.. i m stuck.

UPDATE

VideoCapture did not work for me so i used cvCapture.I thought it wont read sequence of images but it worked.This is what i did

CvCapture* capture = cvCreateFileCapture("Camouflage/b%05d.bmp");

The image name could be anything like b00000, b00010, b00001 etc..

the values in frame3 might be very small. try imshow("Frame Difference",frame3 * 100); — berak, Mar 05 '14 at 11:14

score 0 · Answer 1 · answered Mar 05 '14 at 11:58

0

You are opening a bmp file with VideoCapture. Try a video, but capturing 2 frames without a delay in between may cause some problems.

answered Mar 05 '14 at 11:58

yutasrobot

2,356
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i m reading a sequence of images which is read frame by frame.Anyways, its not working with video as well. – Mohit Rustagi Mar 06 '14 at 03:24

frame difference method[background subtraction]

1 Answers1