OpenCV / C++ - OpenCV 检测鼠标点击位置并显示它，但不画圆

Question

我有这个 OpenCV 代码，每次左键单击鼠标时我都想在图像上画一个圆圈。它检测到我按下左键时鼠标的位置并显示出来，但它没有在该位置画圆。

代码如下：


#include <iostream>
#include <vector>
#include <string>

#include <opencv2/imgproc.hpp>
#include <opencv2/imgcodecs.hpp>
#include <opencv2/highgui.hpp>
#include <opencv2/core.hpp>

cv::Mat inputImage;

void Draw(int event, int x, int y, int flags, void* param)
{
    if (event & cv::EVENT_LBUTTONDOWN)
    {
        std::cout << "X " << x << " Y " << y << std::endl;
        cv::circle(inputImage, cv::Point(x, y), 25, cv::Scalar(0, 255, 0), cv::FILLED, cv::LINE_AA);
    }
}

int main(int argc, char** argv)
{
    std::string path = "C:\Users\dfad\Downloads\dyp.png";
    inputImage = cv::imread(path);

    cv::namedWindow("Image");
    cv::setMouseCallback("Image", Draw, NULL);

    cv::resize(inputImage, inputImage, cv::Size(800, 800), cv::INTER_LINEAR);
    cv::circle(inputImage, cv::Point(130, 130), 10, cv::Scalar(0, 255, 0), cv::FILLED);

    cv::imshow("Image", inputImage);
    cv::waitKey(0);

    return 0;
}

Answer 1

简单地说：

cv::imshow("Image", inputImage);

进入 while 循环，以便在绘制圆圈后更新正在显示的图像。

OpenCV / C++ - OpenCV 检测鼠标点击位置并显示它，但不画圆

OpenCV / C++ - OpenCV detect mouse click position and displays it, but doesn't draw a circle

c++

mouse

opencv

image-processing