WindowsFormsTest/OpenCvSharpTest/ParticleDetectionTest.cs

using OpenCvSharp;
using System;
using System.Drawing;
using System.Drawing.Imaging;
using System.IO;
using System.Windows.Media;
using CvPoint = OpenCvSharp.Point;
using CvSize = OpenCvSharp.Size;

namespace OpenCvSharpTest
{
    public static class ParticleDetectionTest
    {
        public static void ParticleDetectionTest1(Bitmap Bitmapimage)
        {
            //读取图片
            //Bitmap Bitmapimage = new Bitmap("D:\\work\\WindowsFormsTest\\OpenCvSharpTest\\20251108153639.jpg");

            //Mat image = Cv2.ImRead("D:\\work\\WindowsFormsTest\\OpenCvSharpTest\\20251108153840.jpg");
            Mat image = BitmapToMat(Bitmapimage);
            Mat gray = new Mat();

            //灰度化预处理
            Cv2.CvtColor(image, gray, ColorConversionCodes.BGR2GRAY);
            Cv2.ImShow("gray", ReadCodeTest.ResizeMat(gray));

            //二值化
            Mat binary = new Mat();
            Cv2.Threshold(gray, binary, 90, 255, ThresholdTypes.BinaryInv);
            //Cv2.ImShow("binary", ReadCodeTest.ResizeMat(binary));

            //闭运算
            Mat kernelX = new Mat();
            kernelX = Cv2.GetStructuringElement(MorphShapes.Rect, new CvSize(15, 15));
            Mat Open = new Mat();
            Cv2.MorphologyEx(binary, Open, MorphTypes.Erode, kernelX);
            Cv2.ImShow("Opendimg", ReadCodeTest.ResizeMat(Open));

            // 查找轮廓
            CvPoint[][] contours;
            HierarchyIndex[] hierarchy;
            Cv2.FindContours(Open, out contours, out hierarchy,
                RetrievalModes.External, ContourApproximationModes.ApproxSimple);

            double circularityThreshold = 0.7;

            foreach (var blobInfo in contours)
            {
                // 1. 计算轮廓面积
                double area = Cv2.ContourArea(blobInfo);

                // 忽略过小的噪点
                if (area < 100) continue;

                // 2. 计算轮廓周长
                double perimeter = Cv2.ArcLength(blobInfo, true);

                // 避免除以零
                if (perimeter == 0) continue;

                // 3. 计算圆形度: 4 * PI * Area / (Perimeter * Perimeter)
                double circularity = (4 * Math.PI * area) / (perimeter * perimeter);

                // 4. 判断是否满足圆形度要求
                if (circularity > circularityThreshold)
                {
                    // 绘制满足条件的轮廓
                    Cv2.DrawContours(image, new[] { blobInfo }, -1, Scalar.Green, 10);

                    // 可选：在圆心处绘制标记或文字显示圆形度
                    // var moments = Cv2.Moments(contour);
                    // int cx = (int)(moments.M10 / moments.M00);
                    // int cy = (int)(moments.M01 / moments.M00);
                    // Cv2.Circle(image, new CvPoint(cx, cy), 5, Scalar.Red, -1);
                }
            }

            Cv2.ImShow("Output Image", ReadCodeTest.ResizeMat(image));

            //Cv2.WaitKey(0);
        }

        /// <summary>
        /// 将Bitmap转换为Mat(输出为彩色图)
        /// 转换后的图像可以增加彩色框
        /// </summary>
        /// <param name="bitmap">源Bitmap</param>
        /// <returns>对应的Mat对象</returns>
        static Mat BitmapToMat(Bitmap bitmap)
        {
            using (var ms = new MemoryStream())
            {
                bitmap.Save(ms, ImageFormat.Bmp);
                ms.Position = 0;
                return Mat.FromStream(ms, ImreadModes.Color);
            }
        }
    }
}