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This should be the equivalent C++ variant

#include "opencv2/opencv.hpp"

#include <stdio.h>

int main(int argc, char* argv[])
{
    VideoCapture camera (0); // Use the default camera
    Mat frame;

    // capturing some extra frames seems to help stability
    // do this for stability --> give number of iterations, depends on camera
    n = 3;
    for(int i = 0; i < n; i++){
        capture >> frame;
    }

    // with default driver, PSEye is 640 x 480
    Mat hsv_frame (Size(640, 480), CV_8UC3);
    Mat thresholded (Size(640, 480), CV_8UC1);
    Mat thresholded2 (Size(640, 480), CV_8UC1);

    Scalar hsv_min (0, 50, 170); Scalar hsv_min2 (170, 50, 170);
    Scalar hsv_max (10, 180, 256); Scalar hsv_max2 (256, 180, 256);

    camera >> frame;
    if( !frame.empty() ){
        // color detection using HSV
        cvtColor(frame, hsv_frame, CV_BGR2HSV);
        // to handle color wrap-around, two halves are detected and combined
        inRange(hsv_frame, hsv_min, hsv_max, thresholded);
        inRange(hsv_frame, hsv_min2, hsv_max2, thresholded2);
        bitwise_or(thresholded, thresholded2, thresholded);

        imwrite("PATH/thresholded.jpg", thresholded);

        // hough detector works better with some smoothing of the image
        GaussianBlur(thresholded, thresholded, Size(9,9))
        vector<Vec3f> circles;
        HoughCircles(thresholded, circles, CV_HOUGH_GRADIENT, 2, thresholded->height / 4, 100, 40, 20, 200);

        for (int i = 0; i < circles.size(); i++)
        {
            printf("Ball! x=%f y=%f r=%f\n\r", circles[i][0], circles[i][1], circles[i][2]);
            circle(frame, Point((int)circles[i][0], (int)circles[i][1]), 3, CV_RGB(0, 255, 0), -1, 8, 0);
            circle(frame, Point((int)circles[i][0], (int)circles[i][1]), (int)circles[i][2], CV_RGB(255, 0, 0), 3, 8, 0);
        }

        imwrite("PATH/frame.jpg", frame);
    }
    else {
        printf("No frame retrieved! \n");
    }

    return 0;
}

This should be the equivalent C++ variant

#include "opencv2/opencv.hpp"

#include <stdio.h>

using namespace std;
using namespace cv;

int main(int argc, char* argv[])
{
    VideoCapture camera (0); // Use the default camera
    Mat frame;

    // capturing some extra frames seems to help stability
    // do this for stability --> give number of iterations, depends on camera
    int n = 3;
    for(int i = 0; i < n; i++){
        capture camera >> frame;
    }

    // with default driver, PSEye is 640 x 480
    Mat hsv_frame (Size(640, 480), CV_8UC3);
    Mat thresholded (Size(640, 480), CV_8UC1);
    Mat thresholded2 (Size(640, 480), CV_8UC1);

    Scalar hsv_min (0, 50, 170); Scalar hsv_min2 (170, 50, 170);
    Scalar hsv_max (10, 180, 256); Scalar hsv_max2 (256, 180, 256);

    camera >> frame;
    if( !frame.empty() ){
        // color detection using HSV
        cvtColor(frame, hsv_frame, CV_BGR2HSV);
        // to handle color wrap-around, two halves are detected and combined
        inRange(hsv_frame, hsv_min, hsv_max, thresholded);
        inRange(hsv_frame, hsv_min2, hsv_max2, thresholded2);
        bitwise_or(thresholded, thresholded2, thresholded);

        imwrite("PATH/thresholded.jpg", thresholded);

        // hough detector works better with some smoothing of the image
        GaussianBlur(thresholded, thresholded, Size(9,9))
Size(9,9), 0, 0);
        vector<Vec3f> circles;
        HoughCircles(thresholded, circles, CV_HOUGH_GRADIENT, 2, thresholded->height thresholded.rows / 4, 100, 40, 20, 200);

        for (int i = 0; i < circles.size(); i++)
        {
            printf("Ball! x=%f y=%f r=%f\n\r", circles[i][0], circles[i][1], circles[i][2]);
            circle(frame, Point((int)circles[i][0], (int)circles[i][1]), 3, CV_RGB(0, 255, 0), -1, 8, 0);
            circle(frame, Point((int)circles[i][0], (int)circles[i][1]), (int)circles[i][2], CV_RGB(255, 0, 0), 3, 8, 0);
        }

        imwrite("PATH/frame.jpg", frame);
    }
    else {
        printf("No frame retrieved! \n");
    }

    return 0;
}