基于区域生长算法的点云分割（pcl::RegionGrowing）

算法原理：

 

算法流程：

 

代码：

#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 

int
main (int argc, char** argv)
{
  pcl::PointCloud::Ptr cloud (new pcl::PointCloud);
  if ( pcl::io::loadPCDFile  ("region_growing_tutorial.pcd", *cloud) == -1)
  {
    std::cout << "Cloud reading failed." << std::endl;
    return (-1);
  }

  pcl::search::Search::Ptr tree (new pcl::search::KdTree);
  pcl::PointCloud ::Ptr normals (new pcl::PointCloud );
  pcl::NormalEstimation normal_estimator;
  normal_estimator.setSearchMethod (tree);
  normal_estimator.setInputCloud (cloud);
  normal_estimator.setKSearch (50);
  normal_estimator.compute (*normals);

  pcl::IndicesPtr indices (new std::vector );
  pcl::PassThrough pass;
  pass.setInputCloud (cloud);
  pass.setFilterFieldName ("z");
  pass.setFilterLimits (0.0, 1.0);
  pass.filter (*indices);

  pcl::RegionGrowing reg;
  reg.setMinClusterSize (50);
  reg.setMaxClusterSize (1000000);
  reg.setSearchMethod (tree);
  reg.setNumberOfNeighbours (30);
  reg.setInputCloud (cloud);
  //reg.setIndices (indices);
  reg.setInputNormals (normals);
  reg.setSmoothnessThreshold (3.0 / 180.0 * M_PI);
  reg.setCurvatureThreshold (1.0);

  std::vector  clusters;
  reg.extract (clusters);

  std::cout << "Number of clusters is equal to " << clusters.size () << std::endl;
  std::cout << "First cluster has " << clusters[0].indices.size () << " points." << endl;
  std::cout << "These are the indices of the points of the initial" <<
    std::endl << "cloud that belong to the first cluster:" << std::endl;
  int counter = 0;
  while (counter < clusters[0].indices.size ())
  {
    std::cout << clusters[0].indices[counter] << ", ";
    counter++;
    if (counter % 10 == 0)
      std::cout << std::endl;
  }
  std::cout << std::endl;

  pcl::PointCloud ::Ptr colored_cloud = reg.getColoredCloud ();
  pcl::visualization::CloudViewer viewer ("Cluster viewer");
  viewer.showCloud(colored_cloud);
  while (!viewer.wasStopped ())
  {
  }

  return (0);
}

CMakeLists.txt

cmake_minimum_required(VERSION 2.8 FATAL_ERROR)

project(region_growing_segmentation)

find_package(PCL 1.5 REQUIRED)

include_directories(${PCL_INCLUDE_DIRS})
link_directories(${PCL_LIBRARY_DIRS})
add_definitions(${PCL_DEFINITIONS})

add_executable (region_growing_segmentation region_growing_segmentation.cpp)
target_link_libraries (region_growing_segmentation ${PCL_LIBRARIES})

点云文件下载地址：

https://raw.github.com/PointCloudLibrary/data/master/tutorials/region_growing_tutorial.pcd

运行结果：

参考：

http://www.pointclouds.org/documentation/tutorials/region_growing_segmentation.php