详解opencv中画圆circle函数和椭圆ellipse函数

栏目：Linux/apache问题时间：2020-01-04 10:19

1. void ellipse(InputOutputArray img, Point center, Size axes, double angle, double startAngle, double endAngle,

const Scalar& color, int thickness = 1, int lineType = LINE_8, int shift = 0);

ellipse函数将椭圆画到图像 lmg 上，椭圆中心为点center，并且大小位于矩形 axes 内，椭圆旋转角度为 angle，扩展的弧度从 0 度到 360 度，

图形颜色为 Scalar(x， y，z)，线宽 (thickness)为 1，线型(lineType)为 8 (8 联通线型)。

2. void circle(InputOutputArray img, Point center, int radius, const Scalar& color, int thickness = 1, int lineType = LINE_8, int shift = 0);

img :表示输入的图像

center: 圆心坐标

radius: 圆的半径

color：Scalar类型，表示圆的颜色，例如蓝色为Scalar（255,0,0）

thickness:线的宽度

lineType：线的类型，（默认为8联通型）

#include<iostream>
#include<opencv2/opencv.hpp>
using namespace cv;
using namespace std;
#define WINDOW_NAME1 "绘制图1"
#define WINDOW_NAME2 "绘制图2"
#define WINDOW_WIDTH 600  //定义窗口大小
string image = "C:\\Users\\asus\\Pictures\\Saved Pictures\\123.jpg";
void DrawEllipse(Mat img, double angle);
void DrawFi1ledCirc1e(Mat img, Point center);
int main()
{ 
  Mat atomImage = Mat::zeros(WINDOW_WIDTH, WINDOW_WIDTH, CV_8UC3);
  Mat rookImage = Mat::zeros(WINDOW_WIDTH, WINDOW_WIDTH, CV_8UC3);
  //绘制椭圆
  DrawEllipse(atomImage, 90);
  DrawEllipse(atomImage, 0);
  DrawEllipse(atomImage, 45);
  DrawEllipse(atomImage, -45);
  //绘制圆心
  DrawFi1ledCirc1e(atomImage, Point(WINDOW_WIDTH / 2,WINDOW_WIDTH / 2));
  imshow(WINDOW_NAME1, atomImage);
  waitKey(0);
  return 0;
}
void DrawEllipse(Mat img, double angle) {
  int thickness = 2;
  int lineType = 8;
  ellipse(img, Point(WINDOW_WIDTH / 2, WINDOW_WIDTH / 2),
    Size(WINDOW_WIDTH / 4, WINDOW_WIDTH / 16), angle, 0, 360, Scalar(255, 129, 0),
    thickness, lineType);
}
void DrawFi1ledCirc1e(Mat img, Point center) {
  int thickness = -1;
  int lineType = 8;
  circle(img, center, WINDOW_WIDTH / 32, Scalar(0, 0, 255), thickness, lineType);
}