Image Processing

---

A C++ program that uses OpenCV basic tools to create image processing tools.

Looking to implement optimizations so that it runs smoothly for videos.

This project was built using OpenCV

---

Installing the Project

When you clone the repository, create a new directory called build using the following command:

mkdir build

After that, use this command in the build directory to build the cmake files:

cmake ..

It is critical that you perform this command in the build directory

Running the Project

Use the following command to use make to create the executable:

make

Type the following command in the Terminal:

./main <filepath>

Which should open the dev gui where you can manipulate the image using the filter sliders.

---

Or,

./main <filepath>

Which by default, the program will run based on what is put in this section of main.cpp:

else if (argc == 3)
    {
        string three = argv[2];
        if (three.compare("dev") == 0)
        {
            cout << "Dev mode" << endl;

            Image image(argv[1]);

            // Do the specified stuff here

            Mat img = image.getImage();
            namedWindow("Display Image", WINDOW_AUTOSIZE);
            imshow("Display Image", img);

            // Get the current time again
            auto end = chrono::steady_clock::now();
            // Calculate the difference between the start and the end and print the result
            auto elapsed = (chrono::duration_cast<chrono::nanoseconds>(end - start).count() / 1e9);

            cout << "Finished in " << elapsed << "s" << endl;

            waitKey(0);

            return 0;
        }
    }

---

Or lastly,

./main

Which then returns a video stream from whatever camera the program can locate. (It looks at the default camera at index 0). It will run this section where you can manipulate the frames

if (argc == 1) {
        VideoCapture cap(0); // open the video camera no. 0

        Image img;

        if (!cap.isOpened()) {
            cout << "Cannot open the video cam" << endl;
            return -1;
        }

        double dWidth = cap.get(CAP_PROP_FRAME_WIDTH);   //get the width of frames of the video
        double dHeight = cap.get(CAP_PROP_FRAME_HEIGHT); //get the height of frames of the video

        int hthresh, lthresh = 0;
        int thresh = 0;

        namedWindow("Stream", WINDOW_AUTOSIZE);
        createTrackbar("HPF:", "Stream", &hthresh, 100, 0);
        createTrackbar("LPF:", "Stream", &lthresh, 100, 0);
        createTrackbar("Threshold:", "Stream", &thresh, 255, 0);

        while (1) {
            Mat frame;
            bool bSuccess = cap.read(frame); // read a new frame from video
            Mat result;
            double scale = float(dWidth) / frame.size().width;
            resize(frame, result, cv::Size(dWidth / 3, dHeight / 3), scale, scale);
            img.changeImage(result);
            if (hthresh > 0)
            {
                img.highfilter(hthresh);
            }
            if (lthresh > 0)
            {
                img.lowfilter(lthresh);
            }

            img.threshold(thresh);

            if (!bSuccess) //if not success, break loop
            {
                cout << "Cannot read a frame from video stream" << endl;
                break;
            }

            imshow("Stream", img.getImage());

            if (waitKey(30) == 27)
            {
                break;
            }
        }
        return 0;
    }