使用 OpenCV 在图像上绘制椭圆

图像处理 • 2022年11月24日上午11:40 • 技术文章

OpenCV 提供了很多函数来绘制几何形状，例如直线、矩形、圆形等。

该ellipse函数可以通过提供x和y中心坐标、轴长、角度等参数来绘制椭圆或椭圆弧。

import cv2
import numpy as np

img = np.zeros((100, 300, 3), dtype=np.uint8)

center = (150, 50)
axes = (60, 30)
angle = 0
startAngle = 0
endAngle = 360
color = (0, 255, 0)
thickness = 2
cv2.ellipse(img, center, axes, angle, startAngle, endAngle, color, thickness)

cv2.imshow('Image', img)
cv2.waitKey(0)
cv2.destroyAllWindows()

#include <opencv2/opencv.hpp>

using namespace cv;

int main()
{
    Mat img = Mat::zeros(100, 300, CV_8UC3);

    Point center(150, 50);
    Size axes(60, 30);
    int angle = 0;
    int startAngle = 0;
    int endAngle = 360;
    Scalar color(0, 255, 0);
    int thickness = 2;
    ellipse(img, center, axes, angle, startAngle, endAngle, color, thickness);

    imshow("Image", img);
    waitKey(0);
    destroyAllWindows();

    return 0;
}

package app;

import org.opencv.core.*;
import org.opencv.highgui.HighGui;
import org.opencv.imgproc.Imgproc;

public class Main
{
    static { System.loadLibrary(Core.NATIVE_LIBRARY_NAME); }

    public static void main(String[] args)
    {
        Mat img = Mat.zeros(100, 300, CvType.CV_8UC3);

        Point center = new Point(150, 50);
        Size axes = new Size(60, 30);
        int angle = 0;
        int startAngle = 0;
        int endAngle = 360;
        Scalar color = new Scalar(0, 255, 0);
        int thickness = 2;
        Imgproc.ellipse(img, center, axes, angle, startAngle, endAngle, color, thickness);

        HighGui.imshow("Image", img);
        HighGui.waitKey(0);
        HighGui.destroyAllWindows();

        System.exit(0);
    }
}

结果：