opencv学习笔记9 查找绘制轮廓

红太狼 2023-06-04 03:55 33阅读 0赞

## 一。查找绘制轮廓 ##

### 1.查找轮廓 ###

![1615707-20190915145445564-2071640071.png][]

![1615707-20190915145511681-284158982.png][]

###  2.绘制轮廓 ###

![1615707-20190915145610026-1327213964.png][]

![1615707-20190915145624633-746964102.png][]

1 #include<opencv.hpp>
     2 #include<iostream>
     3 #include<vector>
     4 using namespace std;
     5 using namespace cv;
     6 int main()
     7 {
     8     Mat srcImg = imread("F:/opencv/lena.jpg", 0);
     9     imshow("yuantu", srcImg);
    10     Mat dstImg = Mat::zeros(srcImg.rows, srcImg.cols, srcImg.type());
    11     threshold(srcImg, srcImg, 119, 255, THRESH_BINARY);//通过threshold进行二值化
    12     imshow("二值图", srcImg);
    13     vector<vector<Point>>contours; //每个轮廓由多个Point组成，有多个轮廓
    14     vector<Vec4i>hierarchy; //保存每个轮廓的4个信息，hierarchy[i]代表第i个轮廓 hierarchy[i][0]表示第i个轮廓的后一个轮廓
    15     findContours(srcImg, contours, hierarchy, RETR_CCOMP, CHAIN_APPROX_SIMPLE); //寻找轮廓，保存轮廓信息，和轮廓的索引信息
    16     int index = 0; //第1个轮廓的索引
    17     for (; index >= 0; index = hierarchy[index][0]) //index++，若index后面没有对应项，为-1
    18     {
    19         Scalar color(rand() % 255, rand() % 255, rand() % 255);
    20         drawContours(dstImg, contours, index, color, FILLED, 8, hierarchy);//画轮廓
    21     }
    22     imshow("轮廓", dstImg);
    23     waitKey();
    24     return 0;
    25 }

![1615707-20190915145722400-1893701396.png][]

转载于:https://www.cnblogs.com/sclu/p/11522549.html

[1615707-20190915145445564-2071640071.png]: /images/20230601/5c9472bc5db04fb4bb3ec25d2d5c66de.png
[1615707-20190915145511681-284158982.png]: /images/20230601/4407bc4f8e2a425c9d6a372c5bea966d.png
[1615707-20190915145610026-1327213964.png]: /images/20230601/22d5b72f2a7046c1a2c00e90d54db047.png
[1615707-20190915145624633-746964102.png]: /images/20230601/bd1b91998bfb42efa6556d3851410787.png
[1615707-20190915145722400-1893701396.png]: /images/20230601/4463abca97664f2bae3e8d0461efbaba.png