霍夫变换后如何将检测到的相近线段合并并把同一斜率断开的拟合成一条,给个C++示例

以下是一个简单的C++示例代码，实现了对霍夫变换检测到的相近线段进行合并，并将同一斜率的线段拟合成一条直线：

#include <iostream>
#include <vector>
#include <cmath>
#include <algorithm>

using namespace std;

// 定义线段结构体
struct LineSegment {
    int x1, y1, x2, y2; // 线段两个端点坐标
    double slope; // 斜率
};

// 计算两点之间的距离
double distance(int x1, int y1, int x2, int y2) {
    return sqrt(pow(x2 - x1, 2) + pow(y2 - y1, 2));
}

// 计算两点之间的斜率
double slope(int x1, int y1, int x2, int y2) {
    return (double)(y2 - y1) / (x2 - x1);
}

// 判断两条线段是否相交
bool isIntersect(LineSegment l1, LineSegment l2) {
    // 计算线段l1和l2的斜率
    double slope1 = l1.slope;
    double slope2 = l2.slope;

    // 如果斜率相同，不可能相交
    if (slope1 == slope2) {
        return false;
    }

    // 计算线段l1和l2的交点坐标
    double x = (double)(l2.y1 - l1.y1 + slope1 * l1.x1 - slope2 * l2.x1) / (slope1 - slope2);
    double y = (double)(slope1 * (x - l1.x1) + l1.y1);

    // 判断交点是否在两条线段之间
    if (x >= min(l1.x1, l1.x2) && x <= max(l1.x1, l1.x2) &&
        x >= min(l2.x1, l2.x2) && x <= max(l2.x1, l2.x2) &&
        y >= min(l1.y1, l1.y2) && y <= max(l1.y1, l1.y2) &&
        y >= min(l2.y1, l2.y2) && y <= max(l2.y1, l2.y2)) {
        return true;
    }

    return false;
}

// 将相近的线段合并成一条
LineSegment mergeLineSegments(LineSegment l1, LineSegment l2) {
    LineSegment merged;
    merged.x1 = min(l1.x1, l2.x1);
    merged.y1 = min(l1.y1, l2.y1);
    merged.x2 = max(l1.x2, l2.x2);
    merged.y2 = max(l1.y2, l2.y2);
    merged.slope = slope(merged.x1, merged.y1, merged.x2, merged.y2);
    return merged;
}

// 将同一斜率的线段拟合成一条直线
LineSegment fitLine(vector<LineSegment> segments) {
    int n = segments.size();
    double sum_x = 0, sum_y = 0, sum_xy = 0, sum_x2 = 0;
    for (int i = 0; i < n; i++) {
        sum_x += segments[i].x1 + segments[i].x2;
        sum_y += segments[i].y1 + segments[i].y2;
        sum_xy += segments[i].x1 * segments[i].y1 + segments[i].x2 * segments[i].y2;
        sum_x2 += pow(segments[i].x1, 2) + pow(segments[i].x2, 2);
    }
    double mean_x = sum_x / (2 * n);
    double mean_y = sum_y / (2 * n);
    double a = (sum_xy - 2 * n * mean_x * mean_y) / (sum_x2 - 2 * n * pow(mean_x, 2));
    double b = mean_y - a * mean_x;
    LineSegment line;
    line.x1 = 0;
    line.y1 = round(a * line.x1 + b);
    line.x2 = 1000;
    line.y2 = round(a * line.x2 + b);
    line.slope = a;
    return line;
}

int main() {
    // 假设已经通过霍夫变换检测到了多条线段
    vector<LineSegment> segments = {
        {100, 100, 200, 200, 1.0},
        {250, 250, 300, 300, 1.0},
        {400, 400, 500, 500, 1.0},
        {200, 150, 300, 250, 0.5},
        {350, 250, 450, 350, 0.5},
        {500, 350, 600, 450, 0.5},
    };

    // 合并相近的线段
    vector<LineSegment> merged_segments;
    for (int i = 0; i < segments.size(); i++) {
        bool is_merged = false;
        for (int j = 0; j < merged_segments.size(); j++) {
            if (distance(segments[i].x1, segments[i].y1, merged_segments[j].x2, merged_segments[j].y2) < 50 &&
                fabs(segments[i].slope - merged_segments[j].slope) < 0.1) {
                merged_segments[j] = mergeLineSegments(merged_segments[j], segments[i]);
                is_merged = true;
                break;
            }
        }
        if (!is_merged) {
            merged_segments.push_back(segments[i]);
        }
    }

    // 将同一斜率的线段拟合成一条直线
    vector<LineSegment> fitted_lines;
    while (!merged_segments.empty()) {
        vector<LineSegment> same_slope_segments;
        same_slope_segments.push_back(merged_segments.back());
        merged_segments.pop_back();
        for (int i = merged_segments.size() - 1; i >= 0; i--) {
            if (fabs(same_slope_segments.back().slope - merged_segments[i].slope) < 0.1) {
                same_slope_segments.push_back(merged_segments[i]);
                merged_segments.erase(merged_segments.begin() + i);
            }
        }
        fitted_lines.push_back(fitLine(same_slope_segments));
    }

    // 输出拟合后的直线
    for (int i = 0; i < fitted_lines.size(); i++) {
        cout << "Line " << i + 1 << ": (" << fitted_lines[i].x1 << "," << fitted_lines[i].y1 << ") -> (" << fitted_lines[i].x2 << "," << fitted_lines[i].y2 << ")" << endl;
    }

    return 0;
}

以上代码仅供参考，实际应用中可能需要根据具体情况进行调整。