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Here is a very simple approach by comparing the contour and Point in the image. You can adapt this code in what ever language you want! Hope this helps you!

#include <iostream>
#include "opencv2/photo.hpp"
#include "opencv2/imgproc.hpp"
#include "opencv2/imgcodecs.hpp"
#include "opencv2/highgui.hpp"
#include "opencv2/ximgproc/edge_filter.hpp"

#include "opencv2/core.hpp"
#include <iostream>
#include <stdlib.h>

using namespace std;
using namespace cv;

Mat mInput;


static void onMouse( int event, int x, int y, int, void* )
{
    if( event != EVENT_LBUTTONDOWN )
        return;

    Point g_ptMousePoint = Point(x,y);
    Mat mGray,mThres,mThresPad,mResult;
    mResult= mInput.clone();

    RNG rng(12345);
    //Convert to Gray Scale
    cvtColor(mInput,mGray,COLOR_BGR2GRAY);

    //Threshold only darker part
    threshold(mGray,mThres,230,255,THRESH_BINARY_INV);
    //imshow("mThres Wo Border",mThres);

    //Do you need to detect contours at borders? Then add a border
    bool detectOpenAreas=true;
    if(detectOpenAreas)
    {
        Rect rectImage(0,0,mInput.size().width,mInput.size().height);
        rectangle(mThres,rectImage.tl(),rectImage.br(),Scalar(255),4);
        //imshow("mThres",mThres);
    }

    vector<vector<Point> > contours;
    vector<Vec4i> hierarchy;

    /// Find contours
    findContours( mThres.clone(), contours, hierarchy, RETR_TREE, CHAIN_APPROX_SIMPLE, Point(0, 0) );

    for( size_t i = 0; i< contours.size(); i++ )
    {
        //Filter out the Text contours
        if(contourArea(contours[i])>100)
        {
            Scalar color = Scalar( rng.uniform(0, 255), rng.uniform(0,255), rng.uniform(0,255) );                   
            drawContours( mResult, contours, (int)i, color, 1, 8, hierarchy, 0, Point() );                                      
        }       
    }
    //imshow("Result",mResult);

    Mat mCMask(mInput.size(),CV_8UC1,Scalar(0)),mPtMask(mInput.size(),CV_8UC1,Scalar(0)),mResultMask(mInput.size(),CV_8UC1,Scalar(0));
    for( size_t i = 0; i< contours.size(); i++ )
    {
        mCMask.setTo(0);
        mPtMask.setTo(0);                   

        //Filter out the Text contours by Area & Make sure it does not have any child!
        //you add few more filter to this loop like distance from contour mass centre etc...
        if(contourArea(contours[i])> 100 && hierarchy[i][3] != -1 )
        {   
            //Check if Point line on the contour by creating a Mask

            drawContours( mCMask, contours, (int)i, Scalar(255), -1, 8, hierarchy, 0, Point() );                                        
            circle(mPtMask,g_ptMousePoint,1,Scalar(255),-1);
            bitwise_and(mCMask,mPtMask,mResultMask);

            //Check for Non Zero Pixels if > 1 match found
            if(countNonZero(mResultMask)>=1)
            {
                drawContours( mResult, contours, (int)i, Scalar(0,255,0), -1, 8, hierarchy, 0, Point() );
            }       
        }       
    }
    circle(mResult,g_ptMousePoint,2,Scalar(255),-1);
    imshow("Result",mResult);
}

int main( int, char** )
{
    mInput= imread("input.jpg",1);

    namedWindow("Result",WINDOW_AUTOSIZE);  
    imshow("Result",mInput);

    setMouseCallback( "Result", onMouse, 0 );
    cout<<"Please Pick a point!";
    for(;;)
    {           
        int c = waitKey(0);
        if( c == 27 )
        {
            cout << "App Exit ...\n";
            break;
        }
    }   
    destroyAllWindows();
    waitKey(0);
    return 0;
}