08_threshold.cpp

//
// Created by varora on 22/04/24.
//
#include "opencv2/imgproc.hpp"
#include "opencv2/imgcodecs.hpp"
#include "opencv2/highgui.hpp"
#include <iostream>

using namespace cv;
using std::cout;


int threshold_value = 0;
int threshold_type = 3;
int const max_value = 255;
int const max_type = 4;
int const max_binary_value = 255;

Mat src, src_gray, dst;
const char* window_name = "Threshold Demo";

const char* trackbar_type = "Type: \n 0: Binary \n 1: Binary Inverted \n 2: Truncate \n 3: To Zero \n 4: To Zero Inverted";
const char* trackbar_value = "Value";


static void Threshold_Demo( int, void* )
{
    /* 0: Binary
    1: Binary Inverted
    2: Threshold Truncated
    3: Threshold to Zero
    4: Threshold to Zero Inverted
    */
    threshold_type = getTrackbarPos( trackbar_type, window_name );
    threshold_value = getTrackbarPos( trackbar_value, window_name );
    threshold( src_gray, dst, threshold_value, max_binary_value, threshold_type );
    imshow( window_name, dst );
}

int main( int argc, char** argv )
{
    String imageName("ims/sample.jpg"); // by default
    if (argc > 1)
    {
        imageName = argv[1];
    }
    src = imread( samples::findFile( imageName ), IMREAD_COLOR ); // Load an image

    if (src.empty())
    {
        cout << "Cannot read the image: " << imageName << std::endl;
        return -1;
    }

    cvtColor( src, src_gray, COLOR_BGR2GRAY ); // Convert the image to Gray

    namedWindow( window_name, WINDOW_AUTOSIZE ); // Create a window to display results

    createTrackbar( trackbar_type,
                    window_name, NULL,
                    max_type, Threshold_Demo ); // Create a Trackbar to choose type of Threshold

    createTrackbar( trackbar_value,
                    window_name, NULL,
                    max_value, Threshold_Demo ); // Create a Trackbar to choose Threshold value

    Threshold_Demo( 0, 0 ); // Call the function to initialize

    waitKey();
    return 0;
}