• 点云处理【六】(点云分割)


    点云分割

    第一章 点云数据采集
    第二章 点云滤波
    第三章 点云降采样
    第四章 点云关键点检测
    第五章 点云特征提取
    第六章 点云分割
    第七章 点云配准


    1. 点云分割

    点云数据中包含目标物体,点云分割算法即将物体分割出来。

    2 分割算法

    2.1 RANSAC(随机采样一致性)方法

    基于随机采样一致性的分割的步骤如下:
    1.从一个样本集S中,随机抽取n个样本,拟合出一个模型,n是能够初始化模型的最小样本数。
    2.用1中得到的模型去测试所有的其它数据,如果某个点与模型的误差小于某个阈值,则该点适用于这个模型,认为它也是局内点。
    3.如果模型内的局内点达到一定个数,那么估计的模型就足够合理。
    4.用所有假设的局内点去重新执行1,2,估计模型,因为它仅仅被初始的假设局内点估计过。
    5.最后,通过估计局内点与模型的错误率来评估模型。

    平面分割

    open3d

    import open3d as o3d
    import numpy as np
    
    # 读取点云数据
    pcd = o3d.io.read_point_cloud("second_radius_cloud.pcd")
    
    # 使用RANSAC进行平面分割
    plane_model, inliers = pcd.segment_plane(distance_threshold=10,
                                             ransac_n=3,
                                             num_iterations=1000)
    
    # 获取分割出的平面的点云
    inlier_cloud = pcd.select_by_index(inliers)
    inlier_cloud.paint_uniform_color([1.0, 0.5, 0])  # 红色表示平面
    
    # 获取其它点云
    outlier_cloud = pcd.select_by_index(inliers, invert=True)
    
    # 可视化
    o3d.visualization.draw_geometries([inlier_cloud, outlier_cloud],
                                      zoom=0.8,
                                      front=[-0.4999, -0.1659, -0.8499],
                                      lookat=[2.1813, 2.0619, 2.0999],
                                      up=[0.1204, -0.9852, 0.1215])
    
    
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    PCL

    #include 
    #include 
    #include 
    #include 
    #include 
    #include 
    
    int main ()
    {
        // 1. 读取点云数据
        pcl::PointCloud<pcl::PointXYZ>::Ptr cloud (new pcl::PointCloud<pcl::PointXYZ>);
        if (pcl::io::loadPCDFile<pcl::PointXYZ> ("second_radius_cloud.pcd", *cloud) == -1) 
        {
            PCL_ERROR ("Couldn't read the file second_radius_cloud.pcd \n");
            return (-1);
        }
    
        // 2. 创建分割对象和设置参数
        pcl::ModelCoefficients::Ptr coefficients (new pcl::ModelCoefficients ());
        pcl::PointIndices::Ptr inliers (new pcl::PointIndices ());
        pcl::SACSegmentation<pcl::PointXYZ> seg;
        seg.setOptimizeCoefficients (true);
        seg.setModelType (pcl::SACMODEL_PLANE);
        seg.setMethodType (pcl::SAC_RANSAC);
        seg.setMaxIterations (1000);
        seg.setDistanceThreshold (10);
    
        // 3. 进行分割
        seg.setInputCloud (cloud);
        seg.segment (*inliers, *coefficients);
        if (inliers->indices.size () == 0)
        {
            std::cerr << "Could not estimate a planar model for the given dataset." << std::endl;
            return (-1);
        }
    
        // 4. 提取平面
        pcl::ExtractIndices<pcl::PointXYZ> extract;
        pcl::PointCloud<pcl::PointXYZ>::Ptr cloud_plane (new pcl::PointCloud<pcl::PointXYZ> ());
        extract.setInputCloud (cloud);
        extract.setIndices (inliers);
        extract.setNegative (false);
        extract.filter (*cloud_plane);
    
        // 5. 可视化
        pcl::visualization::PCLVisualizer viewer("PCL Plane Segmenter");
        viewer.setBackgroundColor(0, 0, 0);
    
        // 可视化原始点云
        pcl::visualization::PointCloudColorHandlerCustom<pcl::PointXYZ> cloud_color_handler(cloud, 255, 255, 255);
        viewer.addPointCloud(cloud, cloud_color_handler, "original_cloud");
    
        // 可视化平面
        pcl::visualization::PointCloudColorHandlerCustom<pcl::PointXYZ> plane_color_handler(cloud_plane, 0, 255, 0);
        viewer.addPointCloud(cloud_plane, plane_color_handler, "plane_cloud");
        
        viewer.setPointCloudRenderingProperties (pcl::visualization::PCL_VISUALIZER_POINT_SIZE, 2, "original_cloud");
        viewer.setPointCloudRenderingProperties (pcl::visualization::PCL_VISUALIZER_POINT_SIZE, 2, "plane_cloud");
        viewer.initCameraParameters();
        viewer.saveScreenshot("screenshot.png");
        viewer.spin ();
    
        return 0;
    }
    
    
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    2.2 区域生长分割

    随机种下曲率较小的种子后进行延申,根据种子邻域与法线之间的角度与阈值比较,从而判断是否处于哪个领域。

    open3d

    类RegionGrowing.py

    import open3d as o3d
    import numpy as np
    from collections import deque
    
    
    class RegionGrowing:
    
        # 构造函数
        def __init__(self, cloud,
                     min_pts_per_cluster=1,             # 每个聚类的最小点数
                     max_pts_per_cluster=np.inf,        # 每个聚类的最大点数
                     theta_threshold=30,                # 法向量夹角阈值
                     curvature_threshold=0.05,          # 曲率阈值
                     neighbour_number=30,               # 邻域搜索点数
                     point_neighbours=[],               # 近邻点集合
                     point_labels=[],                   # 点标签
                     num_pts_in_segment=[],             # 分类标签
                     clusters=[],                       # 聚类容器
                     number_of_segments=0):             # 聚类个数
    
            self.cure = None                                 # 存储每个点曲率的容器
            self.pcd = cloud                                 # 输入点云
            self.min_pts_per_cluster = min_pts_per_cluster
            self.max_pts_per_cluster = max_pts_per_cluster
            self.theta_threshold = np.deg2rad(theta_threshold)
            self.curvature_threshold = curvature_threshold
            self.neighbour_number = neighbour_number
            self.point_neighbours = point_neighbours
            self.point_labels = point_labels
            self.num_pts_in_segment = num_pts_in_segment
            self.clusters = clusters
            self.number_of_segments = number_of_segments
    
        # -------------------------------------参数准备--------------------------------------
        def prepare_for_segment(self):
            points = np.asarray(self.pcd.points)     # 点坐标
            normals = np.asarray(self.pcd.normals)   # 法向量
            # 判断点云是否为空
            if not points.shape[0]:
                return False
            # 判断是否有近邻点
            if self.neighbour_number == 0:
                return False
            # 点云需要包含法向量信息
            if points.shape[0] != normals.shape[0]:
                self.pcd.estimate_normals(o3d.geometry.KDTreeSearchParamKNN(self.neighbour_number))
    
            return True
    
        # ------------------------------------近邻点搜索-------------------------------------
        def find_neighbour_points(self):
            number = len(self.pcd.points)
            kdtree = o3d.geometry.KDTreeFlann(self.pcd)
            self.point_neighbours = np.zeros((number, self.neighbour_number))
            for ik in range(number):
                [_, idx, _] = kdtree.search_knn_vector_3d(self.pcd.points[ik], self.neighbour_number)  # K近邻搜索
                self.point_neighbours[ik, :] = idx
    
        # -----------------------------------判意点所属分类-----------------------------------
        def validate_points(self, point, nebor):
            is_seed = True
            cosine_threshold = np.cos(self.theta_threshold)  # 法向量夹角(平滑)阈值
    
            curr_seed_normal = self.pcd.normals[point]       # 当前种子点的法向量
            seed_nebor_normal = self.pcd.normals[nebor]      # 种子点邻域点的法向量
            dot_normal = np.fabs(np.dot(seed_nebor_normal, curr_seed_normal))
            # 如果小于平滑阈值
            if dot_normal < cosine_threshold:
                return False, is_seed
            # 如果小于曲率阈值
            if self.cure[nebor] > self.curvature_threshold:
                is_seed = False
    
            return True, is_seed
    
        # ----------------------------------对点附上分类标签----------------------------------
        def label_for_points(self, initial_seed, segment_number):
            seeds = deque([initial_seed])
            self.point_labels[initial_seed] = segment_number
            num_pts_in_segment = 1
    
            while len(seeds):
                curr_seed = seeds[0]
                seeds.popleft()
                i_nebor = 0
                while i_nebor < self.neighbour_number and i_nebor < len(self.point_neighbours[curr_seed]):
                    index = int(self.point_neighbours[curr_seed, i_nebor])
                    if self.point_labels[index] != -1:
                        i_nebor += 1
                        continue
    
                    belongs_to_segment, is_seed = self.validate_points(curr_seed, index)
                    if not belongs_to_segment:
                        i_nebor += 1
                        continue
    
                    self.point_labels[index] = segment_number
                    num_pts_in_segment += 1
    
                    if is_seed:
                        seeds.append(index)
    
                    i_nebor += 1
    
            return num_pts_in_segment
    
        # ------------------------------------区域生长过程------------------------------------
        def region_growing_process(self):
            num_of_pts = len(self.pcd.points)         # 点云点的个数
            self.point_labels = -np.ones(num_of_pts)  # 初始化点标签
            self.pcd.estimate_covariances(o3d.geometry.KDTreeSearchParamKNN(self.neighbour_number))
            cov_mat = self.pcd.covariances            # 获取每个点的协方差矩阵
            self.cure = np.zeros(num_of_pts)          # 初始化存储每个点曲率的容器
            # 计算每个点的曲率
            for i_n in range(num_of_pts):
                eignvalue, _ = np.linalg.eig(cov_mat[i_n])  # SVD分解求特征值
                idx = eignvalue.argsort()[::-1]
                eignvalue = eignvalue[idx]
                self.cure[i_n] = eignvalue[2] / (eignvalue[0] + eignvalue[1] + eignvalue[2])
    
            point_curvature_index = np.zeros((num_of_pts, 2))
            for i_cu in range(num_of_pts):
                point_curvature_index[i_cu, 0] = self.cure[i_cu]
                point_curvature_index[i_cu, 1] = i_cu
    
            # 按照曲率大小进行排序
            temp_cure = np.argsort(point_curvature_index[:, 0])
            point_curvature_index = point_curvature_index[temp_cure, :]
    
            seed_counter = 0
            seed = int(point_curvature_index[seed_counter, 1])  # 选取曲率最小值点
    
            segmented_pts_num = 0
            number_of_segments = 0
    
            while segmented_pts_num < num_of_pts:
                pts_in_segment = self.label_for_points(seed, number_of_segments)  # 根据种子点进行分类
                segmented_pts_num += pts_in_segment
                self.num_pts_in_segment.append(pts_in_segment)
                number_of_segments += 1
    
                # 寻找下一个种子
                for i_seed in range(seed_counter + 1, num_of_pts):
                    index = int(point_curvature_index[i_seed, 1])
                    if self.point_labels[index] == -1:
                        seed = index
                        seed_counter = i_seed
                        break
    
        # ----------------------------------根据标签进行分类-----------------------------------
        def region_growing_clusters(self):
            number_of_segments = len(self.num_pts_in_segment)
            number_of_points = np.asarray(self.pcd.points).shape[0]
    
            # 初始化聚类数组
            for i in range(number_of_segments):
                tmp_init = list(np.zeros(self.num_pts_in_segment[i]))
                self.clusters.append(tmp_init)
    
            counter = list(np.zeros(number_of_segments))
            for i_point in range(number_of_points):
                segment_index = int(self.point_labels[i_point])
                if segment_index != -1:
                    point_index = int(counter[segment_index])
                    self.clusters[segment_index][point_index] = i_point
                    counter[segment_index] = point_index + 1
    
            self.number_of_segments = number_of_segments
    
        # ----------------------------------执行区域生长算法-----------------------------------
        def extract(self):
            if not self.prepare_for_segment():
                print("区域生长算法预处理失败!")
                return
    
            self.find_neighbour_points()
            self.region_growing_process()
            self.region_growing_clusters()
    
            # 根据设置的最大最小点数筛选符合阈值的分类
            all_cluster = []
            for i in range(len(self.clusters)):
                if self.min_pts_per_cluster <= len(self.clusters[i]) <= self.max_pts_per_cluster:
                    all_cluster.append(self.clusters[i])
                else:
                    self.point_labels[self.clusters[i]] = -1
    
            self.clusters = all_cluster
            return all_cluster
    
    
    
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    主程序

    import open3d as o3d
    import numpy as np
    import regiongrowing as reg
    
    # ------------------------------读取点云---------------------------------------
    pcd = o3d.io.read_point_cloud("second_radius_cloud.pcd")
    # ------------------------------区域生长---------------------------------------
    rg = reg.RegionGrowing(pcd,
                           min_pts_per_cluster=500,     # 每个聚类的最小点数
                           max_pts_per_cluster=100000,  # 每个聚类的最大点数
                           neighbour_number=30,         # 邻域搜索点数
                           theta_threshold=30,          # 平滑阈值(角度制)
                           curvature_threshold=0.05)    # 曲率阈值
    # ---------------------------聚类结果分类保存----------------------------------
    indices = rg.extract()
    print("聚类个数为", len(indices))
    segment = []  # 存储分割结果的容器
    for i in range(len(indices)):
        ind = indices[i]
        clusters_cloud = pcd.select_by_index(ind)
        r_color = np.random.uniform(0, 1, (1, 3))  # 分类点云随机赋色
        clusters_cloud.paint_uniform_color([r_color[:, 0], r_color[:, 1], r_color[:, 2]])
        segment.append(clusters_cloud)
    # -----------------------------结果可视化------------------------------------
    o3d.visualization.draw_geometries(segment, window_name="区域生长分割",
                                      width=1024, height=768,
                                      left=50, top=50,
                                      mesh_show_back_face=True)
    
    
    
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    PCL

    #include 
    #include 
    #include 
    #include 
    #include 
    #include 
    #include 
    #include 
    
    int main ()
    {
        // 1. Load point cloud
        pcl::PointCloud<pcl::PointXYZ>::Ptr cloud(new pcl::PointCloud<pcl::PointXYZ>);
        if (pcl::io::loadPCDFile<pcl::PointXYZ>("second_radius_cloud.pcd", *cloud) == -1)
        {
            PCL_ERROR("Couldn't read the file second_radius_cloud.pcd \n");
            return (-1);
        }
    
        // 2. Estimate normals
        pcl::search::Search<pcl::PointXYZ>::Ptr tree(new pcl::search::KdTree<pcl::PointXYZ>);
        pcl::PointCloud<pcl::Normal>::Ptr normals(new pcl::PointCloud<pcl::Normal>);
        pcl::NormalEstimation<pcl::PointXYZ, pcl::Normal> normal_estimator;
        normal_estimator.setSearchMethod(tree);
        normal_estimator.setInputCloud(cloud);
        normal_estimator.setKSearch(300);
        normal_estimator.compute(*normals);
    
        // 3. Apply region growing segmentation
        pcl::RegionGrowing<pcl::PointXYZ, pcl::Normal> reg;
        reg.setMinClusterSize(500);
        reg.setMaxClusterSize(1000000);
        reg.setSearchMethod(tree);
        reg.setNumberOfNeighbours(30);
        reg.setInputCloud(cloud);
        reg.setInputNormals(normals);
        reg.setSmoothnessThreshold(30);  // 3 degrees
        reg.setCurvatureThreshold(0.05);
    
        std::vector<pcl::PointIndices> clusters;
        reg.extract(clusters);
    
        // 4. Visualize the result
        pcl::PointCloud<pcl::PointXYZRGB>::Ptr colored_cloud = reg.getColoredCloud();
        boost::shared_ptr<pcl::visualization::PCLVisualizer> viewer(new pcl::visualization::PCLVisualizer("Region Growing Segmentation"));
        viewer->addPointCloud<pcl::PointXYZRGB>(colored_cloud, "region growing");
        viewer->setBackgroundColor(0, 0, 0);
        viewer->setPointCloudRenderingProperties(pcl::visualization::PCL_VISUALIZER_POINT_SIZE, 1, "region growing");
        viewer->initCameraParameters();
        viewer->saveScreenshot("screenshot.png");
    
        viewer->spin();
    
        return 0;
    }
    
    
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    请添加图片描述

    2.3 欧几里得聚类分割

    根据欧几里得距离的大小将点进行聚类。

    open3d

    import open3d as o3d
    import numpy as np
    import matplotlib.pyplot as plt
    def main():
        pcd = o3d.io.read_point_cloud("second_radius_cloud.pcd")
    
        pcd.estimate_normals(search_param=o3d.geometry.KDTreeSearchParamHybrid(radius=100, max_nn=30))
    
        with o3d.utility.VerbosityContextManager(o3d.utility.VerbosityLevel.Debug) as cm:
            labels = np.array(pcd.cluster_dbscan(eps=20, min_points=10, print_progress=True))
    
        max_label = labels.max()
        print(f"point cloud has {max_label + 1} clusters")
        colors = plt.get_cmap("tab20")(labels / (max_label if max_label > 0 else 1))
        colors[labels < 0] = 0
        pcd.colors = o3d.utility.Vector3dVector(colors[:, :3])
    
        o3d.visualization.draw_geometries([pcd])
    
    if __name__ == "__main__":
        main()
    
    
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    PCL

    #include 
    #include 
    #include 
    #include 
    #include 
    #include 
    #include 
    
    int main ()
    {
        // 1. Load the point cloud data from file
        pcl::PointCloud<pcl::PointXYZ>::Ptr cloud(new pcl::PointCloud<pcl::PointXYZ>);
        if (pcl::io::loadPCDFile<pcl::PointXYZ>("second_radius_cloud.pcd", *cloud) == -1)
        {
            PCL_ERROR("Couldn't read the file second_radius_cloud.pcd \n");
            return (-1);
        }
    
        // 2. Create the KD-Tree object for the search method of the extraction
        pcl::search::KdTree<pcl::PointXYZ>::Ptr tree(new pcl::search::KdTree<pcl::PointXYZ>);
        tree->setInputCloud(cloud);
    
        // 3. Perform the Euclidean Cluster Extraction
        std::vector<pcl::PointIndices> cluster_indices;
        pcl::EuclideanClusterExtraction<pcl::PointXYZ> ec;
        ec.setClusterTolerance(2);
        ec.setMinClusterSize(100);
        ec.setMaxClusterSize(25000);
        ec.setSearchMethod(tree);
        ec.setInputCloud(cloud);
        ec.extract(cluster_indices);
    
        // 4. Visualize the result
        boost::shared_ptr<pcl::visualization::PCLVisualizer> viewer(new pcl::visualization::PCLVisualizer("Euclidean Clustering"));
        viewer->setBackgroundColor(0, 0, 0);
        pcl::PointCloud<pcl::PointXYZRGB>::Ptr colored_cloud = pcl::PointCloud<pcl::PointXYZRGB>::Ptr(new pcl::PointCloud<pcl::PointXYZRGB>());
        int j = 0;
        for (std::vector<pcl::PointIndices>::const_iterator it = cluster_indices.begin(); it != cluster_indices.end(); ++it)
        {
            for (std::vector<int>::const_iterator pit = it->indices.begin(); pit != it->indices.end(); ++pit)
            {
                pcl::PointXYZRGB point;
                point.x = cloud->points[*pit].x;
                point.y = cloud->points[*pit].y;
                point.z = cloud->points[*pit].z;
                point.r = j * 23 % 255;
                point.g = j * 77 % 255;
                point.b = j * 129 % 255;
                colored_cloud->points.push_back(point);
            }
            j++;
        }
        viewer->addPointCloud<pcl::PointXYZRGB>(colored_cloud, "Euclidean Clustering");
        viewer->setPointCloudRenderingProperties(pcl::visualization::PCL_VISUALIZER_POINT_SIZE, 1, "Euclidean Clustering");
        viewer->spin();
    
        return 0;
    }
    
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    PCL

    #include 
    #include 
    #include 
    #include 
    #include 
    #include 
    #include 
    
    int main ()
    {
        // 1. Load the point cloud data from file
        pcl::PointCloud<pcl::PointXYZ>::Ptr cloud(new pcl::PointCloud<pcl::PointXYZ>);
        if (pcl::io::loadPCDFile<pcl::PointXYZ>("second_radius_cloud.pcd", *cloud) == -1)
        {
            PCL_ERROR("Couldn't read the file second_radius_cloud.pcd \n");
            return (-1);
        }
    
        // 2. Create the KD-Tree object for the search method of the extraction
        pcl::search::KdTree<pcl::PointXYZ>::Ptr tree(new pcl::search::KdTree<pcl::PointXYZ>);
        tree->setInputCloud(cloud);
    
        // 3. Perform the Euclidean Cluster Extraction
        std::vector<pcl::PointIndices> cluster_indices;
        pcl::EuclideanClusterExtraction<pcl::PointXYZ> ec;
        ec.setClusterTolerance(2);
        ec.setMinClusterSize(100);
        ec.setMaxClusterSize(25000);
        ec.setSearchMethod(tree);
        ec.setInputCloud(cloud);
        ec.extract(cluster_indices);
    
        // 4. Visualize the result
        boost::shared_ptr<pcl::visualization::PCLVisualizer> viewer(new pcl::visualization::PCLVisualizer("Euclidean Clustering"));
        viewer->setBackgroundColor(0, 0, 0);
        pcl::PointCloud<pcl::PointXYZRGB>::Ptr colored_cloud = pcl::PointCloud<pcl::PointXYZRGB>::Ptr(new pcl::PointCloud<pcl::PointXYZRGB>());
        int j = 0;
        for (std::vector<pcl::PointIndices>::const_iterator it = cluster_indices.begin(); it != cluster_indices.end(); ++it)
        {
            for (std::vector<int>::const_iterator pit = it->indices.begin(); pit != it->indices.end(); ++pit)
            {
                pcl::PointXYZRGB point;
                point.x = cloud->points[*pit].x;
                point.y = cloud->points[*pit].y;
                point.z = cloud->points[*pit].z;
                point.r = j * 23 % 255;
                point.g = j * 77 % 255;
                point.b = j * 129 % 255;
                colored_cloud->points.push_back(point);
            }
            j++;
        }
        viewer->addPointCloud<pcl::PointXYZRGB>(colored_cloud, "Euclidean Clustering");
        viewer->setPointCloudRenderingProperties(pcl::visualization::PCL_VISUALIZER_POINT_SIZE, 1, "Euclidean Clustering");
        viewer->spin();
    
        return 0;
    }
    
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    2.4 霍夫变换分割

    将霍夫变换从2D延申到了3D。

    PCL
    圆柱体检测

    #include 
    #include 
    #include 
    #include 
    #include 
    
    int main()
    {
        // 1. Load Point Cloud data
        pcl::PointCloud<pcl::PointXYZ>::Ptr cloud(new pcl::PointCloud<pcl::PointXYZ>);
        if (pcl::io::loadPCDFile<pcl::PointXYZ>("second_radius_cloud.pcd", *cloud) == -1)
        {
            PCL_ERROR("Couldn't read file second_radius_cloud.pcd \n");
            return (-1);
        }
    
        // 2. Estimate Point Normals
        pcl::NormalEstimation<pcl::PointXYZ, pcl::Normal> ne;
        pcl::PointCloud<pcl::Normal>::Ptr normals(new pcl::PointCloud<pcl::Normal>);
        pcl::search::KdTree<pcl::PointXYZ>::Ptr tree(new pcl::search::KdTree<pcl::PointXYZ>());
        ne.setSearchMethod(tree);
        ne.setInputCloud(cloud);
        ne.setKSearch(50);
        ne.compute(*normals);
    
        // 3. Apply Hough Transform based cylinder segmentation
        pcl::SACSegmentationFromNormals<pcl::PointXYZ, pcl::Normal> seg;
        pcl::PointIndices::Ptr inliers_cylinder(new pcl::PointIndices);
        pcl::ModelCoefficients::Ptr coefficients_cylinder(new pcl::ModelCoefficients);
        seg.setOptimizeCoefficients(true);
        seg.setModelType(pcl::SACMODEL_CYLINDER);
        seg.setMethodType(pcl::SAC_RANSAC);
        seg.setNormalDistanceWeight(0.1);
        seg.setMaxIterations(10000);
        seg.setDistanceThreshold(50);
        seg.setRadiusLimits(0.0, 0.1);
        seg.setInputCloud(cloud);
        seg.setInputNormals(normals);
        seg.segment(*inliers_cylinder, *coefficients_cylinder);
    
        // 4. Visualize the Cylinder
        pcl::visualization::PCLVisualizer::Ptr viewer(new pcl::visualization::PCLVisualizer("Hough Transform Cylinder Segmentation"));
        viewer->setBackgroundColor(0, 0, 0);
        viewer->addPointCloud<pcl::PointXYZ>(cloud, "cloud");
        pcl::PointCloud<pcl::PointXYZ>::Ptr cloud_cylinder(new pcl::PointCloud<pcl::PointXYZ>);
    
        viewer->addPointCloud<pcl::PointXYZ>(cloud_cylinder, "cylinder", 0);
        viewer->setPointCloudRenderingProperties(pcl::visualization::PCL_VISUALIZER_COLOR, 1.0, 0, 0, "cylinder");
    
        while (!viewer->wasStopped())
        {
            viewer->spinOnce(100);
        }
        return 0;
    }
    
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  • 原文地址:https://blog.csdn.net/qq_37249793/article/details/133952357