增加校准通用代码

2026-04-23 19:38:44 +08:00
parent 40b229f5aa
commit b47c261bc3
12 changed files with 1329 additions and 0 deletions
@@ -0,0 +1,161 @@
+using System.Drawing;
+using Emgu.CV;
+using Emgu.CV.CvEnum;
+using Emgu.CV.Structure;
+using Emgu.CV.Util;
+
+namespace XP.Calibration.Core;
+
+/// <summary>
+/// 双球心检测结果
+/// </summary>
+public record DualBallResult
+{
+    /// <summary>第一个球心 (面积较大的)</summary>
+    public PointF Center1 { get; init; }
+    /// <summary>第二个球心 (面积较小的)</summary>
+    public PointF Center2 { get; init; }
+    /// <summary>两球心距离 (像素)</summary>
+    public double DistancePx { get; init; }
+    /// <summary>两球心距离 (mm), 需提供 pixelSize 才有效</summary>
+    public double DistanceMm { get; init; }
+    /// <summary>第一个球的轮廓面积</summary>
+    public double Area1 { get; init; }
+    /// <summary>第二个球的轮廓面积</summary>
+    public double Area2 { get; init; }
+}
+
+/// <summary>
+/// 双球心检测器: 从单帧图像中检测两个球心并计算距离
+/// </summary>
+public static class DualBallDetector
+{
+    /// <summary>
+    /// 检测图像中两个最大球体的中心及距离
+    /// </summary>
+    /// <param name="srcFloat">输入图像 (CV_32F)</param>
+    /// <param name="pixelSize">像素物理尺寸 (mm), 0 表示不计算物理距离</param>
+    /// <param name="minArea">最小轮廓面积阈值, 过滤噪声</param>
+    /// <param name="enableSubPixel">是否启用亚像素质心</param>
+    public static DualBallResult? Detect(
+        Mat srcFloat,
+        double pixelSize = 0,
+        double minArea = 50,
+        bool enableSubPixel = true)
+    {
+        // 归一化 + 预处理
+        using var img8 = new Mat();
+        CvInvoke.Normalize(srcFloat, img8, 0, 255, NormType.MinMax);
+        img8.ConvertTo(img8, DepthType.Cv8U);
+        CvInvoke.GaussianBlur(img8, img8, new Size(3, 3), 0.8);
+
+        // 自适应阈值
+        using var bin = new Mat();
+        CvInvoke.AdaptiveThreshold(img8, bin, 255,
+            AdaptiveThresholdType.MeanC, ThresholdType.Binary, 31, -5);
+
+        // 查找轮廓
+        using var contours = new VectorOfVectorOfPoint();
+        CvInvoke.FindContours(bin, contours, null,
+            RetrType.External, ChainApproxMethod.ChainApproxNone);
+
+        // 按面积排序, 取最大的两个
+        var candidates = new List<(int Index, double Area)>();
+        for (int i = 0; i < contours.Size; i++)
+        {
+            double area = CvInvoke.ContourArea(contours[i]);
+            if (area >= minArea)
+                candidates.Add((i, area));
+        }
+
+        if (candidates.Count < 2)
+            return null;
+
+        candidates.Sort((a, b) => b.Area.CompareTo(a.Area));
+        var top2 = candidates.Take(2).ToList();
+
+        // 计算两个球心
+        var centers = new PointF[2];
+        var areas = new double[2];
+
+        for (int k = 0; k < 2; k++)
+        {
+            int idx = top2[k].Index;
+            areas[k] = top2[k].Area;
+
+            if (enableSubPixel)
+            {
+                using var mask = new Mat(srcFloat.Size, DepthType.Cv8U, 1);
+                mask.SetTo(new MCvScalar(0));
+                CvInvoke.DrawContours(mask, contours, idx, new MCvScalar(255), -1);
+                centers[k] = SubPixelCentroid(srcFloat, mask);
+            }
+            else
+            {
+                var moments = CvInvoke.Moments(contours[idx]);
+                centers[k] = new PointF(
+                    (float)(moments.M10 / moments.M00),
+                    (float)(moments.M01 / moments.M00));
+            }
+        }
+
+        // 计算距离
+        double dx = centers[0].X - centers[1].X;
+        double dy = centers[0].Y - centers[1].Y;
+        double distPx = Math.Sqrt(dx * dx + dy * dy);
+        double distMm = pixelSize > 0 ? distPx * pixelSize : 0;
+
+        return new DualBallResult
+        {
+            Center1 = centers[0],
+            Center2 = centers[1],
+            DistancePx = distPx,
+            DistanceMm = distMm,
+            Area1 = areas[0],
+            Area2 = areas[1]
+        };
+    }
+
+    /// <summary>
+    /// 从 8bit 图像检测 (便捷重载, 支持 CV_8U 输入)
+    /// </summary>
+    public static DualBallResult? DetectFrom8U(
+        Mat src8U,
+        double pixelSize = 0,
+        double minArea = 50,
+        bool enableSubPixel = true)
+    {
+        using var floatMat = new Mat();
+        src8U.ConvertTo(floatMat, DepthType.Cv32F);
+        return Detect(floatMat, pixelSize, minArea, enableSubPixel);
+    }
+
+    private static PointF SubPixelCentroid(Mat imgFloat, Mat mask)
+    {
+        double sumI = 0, sumX = 0, sumY = 0;
+        var imgData = imgFloat.GetData() as float[,];
+        var maskData = mask.GetData() as byte[,];
+
+        if (imgData == null || maskData == null)
+            return new PointF(-1, -1);
+
+        for (int y = 0; y < imgFloat.Rows; y++)
+        {
+            for (int x = 0; x < imgFloat.Cols; x++)
+            {
+                if (maskData[y, x] != 0)
+                {
+                    double intensity = imgData[y, x];
+                    sumI += intensity;
+                    sumX += x * intensity;
+                    sumY += y * intensity;
+                }
+            }
+        }
+
+        if (sumI == 0)
+            return new PointF(-1, -1);
+
+        return new PointF((float)(sumX / sumI), (float)(sumY / sumI));
+    }
+}