CannyStill.cpp

// CannyStill.cpp

#include<opencv2/opencv.hpp>

#include<iostream>
#include<conio.h>           // may have to modify this line if not using Windows

///////////////////////////////////////////////////////////////////////////////////////////////////
int main() {
    cv::Mat imgOriginal;        // input image
    cv::Mat imgGrayscale;       // grayscale of input image
    cv::Mat imgBlurred;         // intermediate blured image
    cv::Mat imgCanny;           // Canny edge image

    imgOriginal = cv::imread("image.png");          // open image

    if (imgOriginal.empty()) {                                  // if unable to open image
        std::cout << "error: image not read from file\n\n";     // show error message on command line
        _getch();                                               // may have to modify this line if not using Windows
        return(0);                                              // and exit program
    }

    cv::cvtColor(imgOriginal, imgGrayscale, CV_BGR2GRAY);       // convert to grayscale

    cv::GaussianBlur(imgGrayscale,          // input image
        imgBlurred,                         // output image
        cv::Size(5, 5),                     // smoothing window width and height in pixels
        1.5);                               // sigma value, determines how much the image will be blurred

    cv::Canny(imgBlurred,           // input image
        imgCanny,                   // output image
        82,                         // low threshold
        164);                       // high threshold

                                    // declare windows
    cv::namedWindow("imgOriginal", CV_WINDOW_AUTOSIZE);     // note: you can use CV_WINDOW_NORMAL which allows resizing the window
    cv::namedWindow("imgCanny", CV_WINDOW_AUTOSIZE);        // or CV_WINDOW_AUTOSIZE for a fixed size window matching the resolution of the image
                                                            // CV_WINDOW_AUTOSIZE is the default
    cv::imshow("imgOriginal", imgOriginal);     // show windows
    cv::imshow("imgCanny", imgCanny);

    cv::waitKey(0);                 // hold windows open until user presses a key

    return(0);
}