opencv+codeblocks +anaconda

study from :

https://www.jianshu.com/p/c16b7c870356

 #include <cstdio>
 #include <cstdlib>
 #include <cmath>
 #include <cstring>
 #include <string>
 #include <algorithm>
 #include <set>
 #include <map>
 #include <queue>
 #include <iostream>
 #include <opencv2\core\core.hpp>
 #include <opencv2\highgui\highgui.hpp>
 #include <opencv2\imgproc\imgproc.hpp>
 using namespace std;
 using namespace cv;

 #define ll long long

 const int maxn=1e4+;
 const int inf=1e9;
 const double eps=1e-;

 int main()
 {
     Mat img=imread("C:\\Users\\scientific\\Desktop\\test.jpg"); //两个'\'
     imshow("test",img);
     waitKey();
     return ;
 }
 /*

 */

加入问价的路径要写对，否则运行程序，会出现

codeblocks error: ld returnd 1 exit status

即使你没用opencv也会出现这个问题，编译运行时会找那些内容，然后某个内容没有，就会报错。

图像一闪而过

waitKey (0);

waitKey()

①等待x ms，如果在此期间有按键按下，则立即结束并返回按键的ASCII码，否则返回-1；

②如果x=0，则无限等待下去，直到有按键按下；

【注】：在imshow之后，如果没有waitKey语句则不会显示图像。

(study from : https://jingyan.baidu.com/article/93f9803f522b5ce0e56f557c.html)

 #include<opencv2/core/core.hpp>        // 核心组件
 #include<opencv2/highgui/highgui.hpp>  // GUI
 #include<opencv2/imgproc/imgproc.hpp>  // 图像处理

(study from : https://blog.csdn.net/francislucien2017/article/details/80962830)

imwrite  要加后缀名

前后两张图片大小不一样

cv::Mat img=imread("test1.jpg"); imwrite("test2.jpg",img);

无法使用imshow、cvtColor，不知道为什么

遇到控制台无法关闭，使用

study from : https://blog.csdn.net/huyaoyu/article/details/80796442

+ - * / 重载运算符 更快

 #include <cstdio>
 #include <cstdlib>
 #include <cmath>
 #include <cstring>
 #include <string>
 #include <algorithm>
 #include <set>
 #include <map>
 #include <queue>
 #include <iostream>
 #include <opencv2/opencv.hpp>
 #include <opencv2\core\core.hpp>
 #include <opencv2\highgui\highgui.hpp>
 #include <opencv2\imgproc\imgproc.hpp>
 using namespace std;
 using namespace cv;

 #define ll long long

 const int maxn=1e4+;
 const int inf=1e9;
 const double eps=1e-;

 int main()
 {
     Mat img=imread("test1.jpg");
 //    imwrite("test2.jpg",img);

     ///
     Mat M(,, CV_8UC3, Scalar(,,));
     cout << "M = " << endl << " " << M << endl << endl;
     cout<<M.rows<<" "<<M.cols<<" "<<M.dims<<" "<<M.size()<<M.channels();
     imwrite("test3.jpg",M);

     Mat gray_image;
     cvtColor(M,gray_image,CV_BGR2GRAY); ///只有channels =3/4[4 透明度] 时才行
     imwrite("test4.jpg",gray_image);

     ///
 //    Mat M1;
 //    M1.create(4,4, CV_8UC(2));
 //    cout << "M1 = "<< endl << " "  << M1 << endl << endl;

     //求连通块，统计个数 opencv 读入图片，读出图片
     ///选择使用的连通块用红点标注

     return ;
 }
 /*

 */

opencv教程

背景 http://c.biancheng.net/opencv/

https://blog.csdn.net/w_k_l/article/details/74887145

https://blog.csdn.net/w_k_l/article/details/79644960

https://docs.opencv.org/master/d9/df8/tutorial_root.html

如mat : ttps://docs.opencv.org/master/d6/d6d/tutorial_mat_the_basic_image_container.html

github上的项目

opencv+anaconda

study from :

https://blog.csdn.net/iracer/article/details/80498732