一、安装包

<PackageReference Include="OpenCvSharp4" Version="4.10.0.20241108" />
<PackageReference Include="OpenCvSharp4.runtime.win" Version="4.10.0.20241108" />

二、准备两张图片

三、编写代码

using OpenCvSharp;
using System;
using System.Diagnostics;
using System.IO;
using static OpenCvSharp.FileStorage;
using static System.Net.Mime.MediaTypeNames;namespace OpenCvSharpDemo
{internal class Program{static void Main(string[] args){Compare();}static void Compare(){var path1 = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "Images/A1.png");var path2 = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "Images/A2.png");// 读取两张图片Mat image1 = Cv2.ImRead(path1, ImreadModes.Color);Mat image2 = new Mat();Cv2.Resize(Cv2.ImRead(path2, ImreadModes.Color), image2, new OpenCvSharp.Size(image1.Size().Width, image1.Size().Height));if (image1.Empty() || image2.Empty()){Console.WriteLine("无法正确读取图片，请检查图片路径是否正确。");return;}// 确保两张图片尺寸一致，如果不一致可以进行调整（这里简单示例假设尺寸相同）if (image1.Size() != image2.Size()){Console.WriteLine("两张图片尺寸不一致，请先处理为相同尺寸。");return;}// 计算两张图片像素差值（逐像素相减）Mat diff = new Mat();Cv2.Absdiff(image1, image2, diff);// 将差异图像转换为灰度图（方便后续阈值处理等操作）Mat grayDiff = new Mat();Cv2.CvtColor(diff, grayDiff, ColorConversionCodes.BGR2GRAY);//膨胀3次var kernel = Cv2.GetStructuringElement(MorphShapes.Rect, new OpenCvSharp.Size(5, 5));Cv2.Dilate(grayDiff, grayDiff, kernel, null, 3);// 应用阈值，将差异明显的地方凸显出来，这里阈值可以根据实际情况调整Mat thresholded = new Mat();Cv2.Threshold(grayDiff, thresholded, 30, 255, ThresholdTypes.Binary);// 查找轮廓，轮廓所在区域就是不同之处Point[][] contours;HierarchyIndex[] hierarchy;Cv2.FindContours(thresholded, out contours, out hierarchy, RetrievalModes.Tree, ContourApproximationModes.ApproxSimple);// 在原始图片（这里选择image1）上绘制出不同之处的轮廓（标记为红色）for (int i = 0; i < contours.Length; i++){Cv2.DrawContours(image1, contours, i, new Scalar(0, 0, 255), 2);}// 显示标记出不同之处的图片Cv2.ImShow("Differences", image1);Cv2.WaitKey(0);Cv2.DestroyAllWindows();}}
}

运行：