[Point Cloud Library] 使用直通滤波器过滤点云

这个教程学习如何使用简单的滤波器，沿着指定维，过滤掉指定范围内外的值。

 

#include <iostream>
#include <pcl/point_types.h>
#include <pcl/filters/passthrough.h>

int
 main (int argc, char** argv)
{
  pcl::PointCloud<pcl::PointXYZ>::Ptr cloud (new pcl::PointCloud<pcl::PointXYZ>);
  pcl::PointCloud<pcl::PointXYZ>::Ptr cloud_filtered (new pcl::PointCloud<pcl::PointXYZ>);

  // Fill in the cloud data
  cloud->width  = 5;
  cloud->height = 1;
  cloud->points.resize (cloud->width * cloud->height);

  for (size_t i = 0; i < cloud->points.size (); ++i)
  {
    cloud->points[i].x = 1024 * rand () / (RAND_MAX + 1.0f);
    cloud->points[i].y = 1024 * rand () / (RAND_MAX + 1.0f);
    cloud->points[i].z = 1024 * rand () / (RAND_MAX + 1.0f);
  }

  std::cerr << "Cloud before filtering: " << std::endl;
  for (size_t i = 0; i < cloud->points.size (); ++i)
    std::cerr << "    " << cloud->points[i].x << " " 
                        << cloud->points[i].y << " " 
                        << cloud->points[i].z << std::endl;

  // Create the filtering object
  pcl::PassThrough<pcl::PointXYZ> pass;
  pass.setInputCloud (cloud);
  pass.setFilterFieldName ("z");
  pass.setFilterLimits (0.0, 1.0);
  //pass.setFilterLimitsNegative (true);
  pass.filter (*cloud_filtered);

  std::cerr << "Cloud after filtering: " << std::endl;
  for (size_t i = 0; i < cloud_filtered->points.size (); ++i)
    std::cerr << "    " << cloud_filtered->points[i].x << " " 
                        << cloud_filtered->points[i].y << " " 
                        << cloud_filtered->points[i].z << std::endl;

  return (0);
}

一步一步来分析这些代码。

首先，我们创建一个PointCloud，填充数据。

然后创建一个直通滤波器并且设置参数。过滤器字段的名字设置为“Z”，接受的区间值设置为(0.0, 1.0)；

即：保留z轴上z值为0.0-1.0之间的值的点，其他点均过滤掉。

运行程序，你会看到类似如下的结果。

 

Cloud before filtering:
    0.352222 -0.151883 -0.106395
    -0.397406 -0.473106 0.292602
    -0.731898 0.667105 0.441304
    -0.734766 0.854581 -0.0361733
    -0.4607 -0.277468 -0.916762
Cloud after filtering:
    -0.397406 -0.473106 0.292602
    -0.731898 0.667105 0.441304

 

http://blog.csdn.net/leowangzi/article/details/7838554