两个2维点集匹配定位的C#代码实现
以下是两个2维点集匹配定位的C#代码实现示例:
using System;
namespace PointMatching
{
class Program
{
static void Main(string[] args)
{
// 两个点集
double[,] points1 = { { 1, 2 }, { 3, 4 }, { 5, 6 }, { 7, 8 } };
double[,] points2 = { { 2, 2 }, { 4, 4 }, { 6, 6 }, { 8, 8 } };
// 初始化RANSAC算法
RANSAC ransac = new RANSAC(points1, points2);
// 运行RANSAC算法
ransac.Run(100, 0.1);
// 输出结果
Console.WriteLine("平移:(" + ransac.TranslationX + ", " + ransac.TranslationY + ")");
Console.WriteLine("旋转角度:" + ransac.RotationAngle);
Console.WriteLine("缩放比例:" + ransac.Scale);
Console.ReadLine();
}
}
class RANSAC
{
private double[,] _points1;
private double[,] _points2;
private double _translationX;
private double _translationY;
private double _rotationAngle;
private double _scale;
public double TranslationX
{
get { return _translationX; }
}
public double TranslationY
{
get { return _translationY; }
}
public double RotationAngle
{
get { return _rotationAngle; }
}
public double Scale
{
get { return _scale; }
}
public RANSAC(double[,] points1, double[,] points2)
{
_points1 = points1;
_points2 = points2;
}
public void Run(int iterations, double threshold)
{
Random random = new Random();
double bestScore = 0;
for (int i = 0; i < iterations; i++)
{
// 随机选择3个点
int index1 = random.Next(_points1.GetLength(0));
int index2 = random.Next(_points1.GetLength(0));
int index3 = random.Next(_points1.GetLength(0));
// 计算平移量、旋转角度和缩放比例
double tx = _points2[index1, 0] - (_points1[index1, 0] * Math.Cos(_rotationAngle) - _points1[index1, 1] * Math.Sin(_rotationAngle)) * _scale;
double ty = _points2[index1, 1] - (_points1[index1, 0] * Math.Sin(_rotationAngle) + _points1[index1, 1] * Math.Cos(_rotationAngle)) * _scale;
double a = (_points2[index2, 1] - ty) / (_points1[index2, 1] * Math.Cos(_rotationAngle) + _points1[index2, 0] * Math.Sin(_rotationAngle) - _points1[index2, 1] * Math.Sin(_rotationAngle) + _points1[index2, 0] * Math.Cos(_rotationAngle));
double b = (_points2[index3, 0] - tx) / (_points1[index3, 0] * Math.Cos(_rotationAngle) - _points1[index3, 1] * Math.Sin(_rotationAngle) - _points1[index3, 0] * Math.Sin(_rotationAngle) - _points1[index3, 1] * Math.Cos(_rotationAngle));
double scale = (a + b) / 2;
double angle = Math.Atan2(_points2[index1, 1] - ty, _points2[index1, 0] - tx) - Math.Atan2(_points1[index1, 1] * Math.Cos(_rotationAngle) + _points1[index1, 0] * Math.Sin(_rotationAngle) - _points1[index1, 1] * Math.Sin(_rotationAngle) + _points1[index1, 0] * Math.Cos(_rotationAngle), _points1[index1, 0] * Math.Cos(_rotationAngle) - _points1[index1, 1] * Math.Sin(_rotationAngle) - _points1[index1, 0] * Math.Sin(_rotationAngle) - _points1[index1, 1] * Math.Cos(_rotationAngle));
// 计算匹配分数
double score = 0;
int count = 0;
for (int j = 0; j < _points1.GetLength(0); j++)
{
double x = _points1[j, 0] * Math.Cos(angle) - _points1[j, 1] * Math.Sin(angle);
double y = _points1[j, 0] * Math.Sin(angle) + _points1[j, 1] * Math.Cos(angle);
x *= scale;
y *= scale;
x += tx;
y += ty;
double dx = x - _points2[j, 0];
double dy = y - _points2[j, 1];
if (dx * dx + dy * dy < threshold * threshold)
{
score++;
}
count++;
}
if (score / count > bestScore)
{
_translationX = tx;
_translationY = ty;
_rotationAngle = angle;
_scale = scale;
bestScore = score / count;
}
}
}
}
}
该代码实现使用RANSAC算法进行点集匹配定位。该算法随机选择3个点,计算平移量、旋转角度和缩放比例,并根据这些参数将第一个点集变换到与第二个点集匹配的位置。然后,算法计算匹配分数,即点集中有多少点与变换后的点集中的点距离小于指定阈值。算法循环运行多次,并选择匹配分数最高的变换作为最终结果。
原文地址: https://www.cveoy.top/t/topic/s5p 著作权归作者所有。请勿转载和采集!