添加NuGet包

选择最新版就好了

安装完成后右键项目重新生成方案

使用OpenCvSharp.CPlusPlus命名空间

using OpenCvSharp.CPlusPlus;

写一个函数用来改变图片大小并且重新命名

read_path是存储图片的文件夹的路径，write_path是改变后图片存储的文件夹路径，filename是图片重命名，width和height分别为图片修改后的宽和高

public static void ResizeImg(String read_path,String write_path,String filename,double width,double height) {      Mat img1 = new Mat(read_path);      Mat img2 = img1;      OpenCvSharp.CPlusPlus.Size size = new OpenCvSharp.CPlusPlus.Size(width, height);      Cv2.Resize(img1, img2, size, 0, 0);      Cv2.ImWrite(write_path+"\\"+ filename, img2);    }

在Main函数中使用该函数

static void Main(string[] args)    {      string dir_path = @"G:\TestImg";//读取路径      String write_path = "G:\\TestImg2";//存储路径      String[] filenames=Directory.GetFiles(dir_path);      for (int i = 0; i < filenames.Length; i++) {        ResizeImg(filenames[i], write_path, i + ".png", 200, 300);      }      Console.ReadKey();    }

运行结果

完整代码

using System;using System.Collections.Generic;using System.Drawing;using System.Linq;using System.Text;using System.Threading.Tasks;using OpenCvSharp;using OpenCvSharp.CPlusPlus;using System.Runtime.InteropServices;using System.IO;namespace ResizeTest{  class Program  {    static void Main(string[] args)    {      string dir_path = @"G:\TestImg";//读取路径      String write_path = "G:\\TestImg2";//存储路径      String[] filenames=Directory.GetFiles(dir_path);      for (int i = 0; i < filenames.Length; i++) {        ResizeImg(filenames[i], write_path, i + ".png", 200, 300);      }      Console.ReadKey();    }    public static void ResizeImg(String read_path,String write_path,String filename,double width,double height) {      Mat img1 = new Mat(read_path);      Mat img2 = img1;      OpenCvSharp.CPlusPlus.Size size = new OpenCvSharp.CPlusPlus.Size(width, height);      Cv2.Resize(img1, img2, size, 0, 0);      Cv2.ImWrite(write_path+"\\"+ filename, img2);    }  }  }