c# 圆形识别方案和直线识别方案的参考示例

 public static bool IsCircle(List points, out Point center, out double radius) { int len = points.Count; center = new Point(); radius = 0; // 判断是否为封闭图形 if (!IsClosedFigure(points)) return false; int judgePointNum = len * 50 / 100; if (len  MaxRatio) return false; } return true; }

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 /// 最小二乘法求回归直线方程 /// 
 /// 输入数据 /// 直线斜率 /// 直线截距 /// 直线类型 1：水平线 2：垂直线 3：一般直线 ///  public static bool IsLine(List points, out double k, out double b, out int type) { k = 0; b = 0; type = 0; if (points.Count <2) return false; double averageX = 0, averageY = 0, n = 0; n = points.Count; foreach (Point p in points) { averageX += p.X; averageY += p.Y; } averageX /= n; averageY /= n; double numerator = 0, denominator = 0; foreach (Point p in points) { numerator += (p.X - averageX) * (p.Y - averageY); denominator += (p.X - averageX) * (p.X - averageX); } if (numerator == 0) //平行于X轴为水平线，返回纵坐标平均值 { b = averageY; type = 1; } else if (denominator == 0)//平行于Y轴为垂直线，返回横坐标平均值 { b = averageX; type = 2; } else { type = 3; } k = numerator / denominator; b = averageY - k * averageX; foreach (Point p in points) { dis = GetPoint2LineDistance(p, k, b, type); if (dis > MAX_POINT_LINE_DIS) return false; //点到拟合直线距离过大 } return true; } /// 
 /// 计算点到直线的距离 /// 
 /// 待计算点 /// 直线斜率 /// 直线截距 /// 直线类型 1：水平线 2：垂直线 3：一般直线 /// 距离 private static double GetPoint2LineDistance(Point p, double k, double b, int type) { if (type == 1) { return Math.Abs(p.Y - b); } else if (type == 2) { return Math.Abs(p.X - b); } else { double numerator = 0, denominator = 0; numerator = Math.Abs(k * p.X - p.Y + b); denominator = Math.Sqrt(k * k + 1); return numerator / denominator; } }