PCL：使用VoxelGrid filter对点云进行下采样

使用VoxelGrid filter对点云进行下采样，VoxelGrid可以堪称是个小的3D小方盒， 所有存在的点将以它们的质心近似（如，下采样）。这种方法比使用体素的中心近似慢，但它更准确地表示底层表面。

#include <iostream>#include <pcl/io/pcd_io.h>#include <pcl/point_types.h>#include <pcl/filters/voxel_grid.h>intmain (int argc, char** argv){  pcl::PCLPointCloud2::Ptr cloud (new pcl::PCLPointCloud2 ());  pcl::PCLPointCloud2::Ptr cloud_filtered (new pcl::PCLPointCloud2 ());  // Fill in the cloud data  pcl::PCDReader reader;  // Replace the path below with the path where you saved your file  reader.read ("table_scene_lms400.pcd", *cloud); // Remember to download the file first!  std::cerr << "PointCloud before filtering: " << cloud->width * cloud->height        << " data points (" << pcl::getFieldsList (*cloud) << ").";  // Create the filtering object  pcl::VoxelGrid<pcl::PCLPointCloud2> sor;  sor.setInputCloud (cloud);  sor.setLeafSize (0.01f, 0.01f, 0.01f);  sor.filter (*cloud_filtered);  std::cerr << "PointCloud after filtering: " << cloud_filtered->width * cloud_filtered->height        << " data points (" << pcl::getFieldsList (*cloud_filtered) << ").";  pcl::PCDWriter writer;  writer.write ("table_scene_lms400_downsampled.pcd", *cloud_filtered,          Eigen::Vector4f::Zero (), Eigen::Quaternionf::Identity (), false);  return (0);}

这里就只写一次CMakeLists.txt,其他的使用PCL都是类似的

cmake_minimum_required(VERSION 2.8 FATAL_ERROR)project(voxelgrid_filter)//add PCL dependencyfind_package(PCL 1.7 REQUIRED)include_directories(${PCL_INCLUDE_DIRS})link_directories(${PCL_LIBRARY_DIRS})add_definitions(${PCL_DEFINITION})add_executable(voxelgrid_filter main.cpp)target_link_libraries(voxelgrid_filter ${PCL_LIBRARIES})install(TARGETS voxelgrid_filter RUNTIME DESTINATION bin)

看到点云的数量几乎变成原来的十分之一。。。。

可以看到橙色是原来采样之前的点是比较密集的，蓝色的是采样后的点，就变得相对来说更加稀疏了，如果继续修改LeafSize，还可以进行更加稀疏的采样，当过于稀疏会使得点云信息减少，对后续的操作不利。