Point Cloud Library (PCL)  1.3.1
Classes | Public Types | Public Member Functions
pcl::VoxelGrid Class Reference

VoxelGrid assembles a local 3D grid over a given PointCloud, and downsamples + filters the data. More...

#include <pcl/filters/voxel_grid.h>

Inheritance diagram for pcl::VoxelGrid:
Inheritance graph
[legend]
Collaboration diagram for pcl::VoxelGrid:
Collaboration graph
[legend]

List of all members.

Classes

struct  Leaf
 Simple structure to hold an nD centroid and the number of points in a leaf. More...

Public Types

typedef boost::shared_ptr
< Filter< PointT > > 
Ptr
typedef boost::shared_ptr
< const Filter< PointT > > 
ConstPtr

Public Member Functions

 VoxelGrid ()
 Empty constructor.
virtual ~VoxelGrid ()
 Destructor.
void setLeafSize (const Eigen::Vector4f &leaf_size)
 Set the voxel grid leaf size.
void setLeafSize (float lx, float ly, float lz)
 Set the voxel grid leaf size.
Eigen::Vector3f getLeafSize ()
 Get the voxel grid leaf size.
void setDownsampleAllData (bool downsample)
 Set to true if all fields need to be downsampled, or false if just XYZ.
bool getDownsampleAllData ()
 Get the state of the internal downsampling parameter (true if all fields need to be downsampled, false if just XYZ).
void setSaveLeafLayout (bool save_leaf_layout)
 Set to true if leaf layout information needs to be saved for later access.
bool getSaveLeafLayout ()
 Returns true if leaf layout information will to be saved for later access.
Eigen::Vector3i getMinBoxCoordinates ()
 Get the minimum coordinates of the bounding box (after filtering is performed).
Eigen::Vector3i getMaxBoxCoordinates ()
 Get the minimum coordinates of the bounding box (after filtering is performed).
Eigen::Vector3i getNrDivisions ()
 Get the number of divisions along all 3 axes (after filtering is performed).
Eigen::Vector3i getDivisionMultiplier ()
 Get the multipliers to be applied to the grid coordinates in order to find the centroid index (after filtering is performed).
int getCentroidIndex (const PointT &p)
 Returns the index in the resulting downsampled cloud of the specified point.
std::vector< int > getNeighborCentroidIndices (const PointT &reference_point, const Eigen::MatrixXi &relative_coordinates)
 Returns the indices in the resulting downsampled cloud of the points at the specified grid coordinates, relative to the grid coordinates of the specified point (or -1 if the cell was empty/out of bounds).
std::vector< int > getLeafLayout ()
 Returns the layout of the leafs for fast access to cells relative to current position.
Eigen::Vector3i getGridCoordinates (float x, float y, float z)
 Returns the corresponding (i,j,k) coordinates in the grid of point (x,y,z).
int getCentroidIndexAt (const Eigen::Vector3i &ijk, bool verbose=true)
 Returns the index in the downsampled cloud corresponding to coordinates (i,j,k) in the grid (-1 if empty)
IndicesConstPtr const getRemovedIndices ()
 Get the point indices being removed.
void setFilterFieldName (const std::string &field_name)
 Provide the name of the field to be used for filtering data.
std::string const getFilterFieldName ()
 Get the name of the field used for filtering.
void setFilterLimits (const double &limit_min, const double &limit_max)
 Set the field filter limits.
void getFilterLimits (double &limit_min, double &limit_max)
 Get the field filter limits (min/max) set by the user.
void setFilterLimitsNegative (const bool limit_negative)
 Set to true if we want to return the data outside the interval specified by setFilterLimits (min, max).
void getFilterLimitsNegative (bool &limit_negative)
 Get whether the data outside the interval (min/max) is to be returned (true) or inside (false).
bool getFilterLimitsNegative ()
void filter (PointCloud &output)
 Calls the filtering method and returns the filtered dataset in output.

Detailed Description

VoxelGrid assembles a local 3D grid over a given PointCloud, and downsamples + filters the data.

The VoxelGrid class creates a *3D voxel grid* (think about a voxel grid as a set of tiny 3D boxes in space) over the input point cloud data. Then, in each *voxel* (i.e., 3D box), all the points present will be approximated (i.e., *downsampled*) with their centroid. This approach is a bit slower than approximating them with the center of the voxel, but it represents the underlying surface more accurately.

Author:
Radu Bogdan Rusu, Bastian Steder

Member Typedef Documentation

typedef boost::shared_ptr< const Filter<PointT> > pcl::Filter::ConstPtr [inherited]

Definition at line 75 of file filter.h.

typedef boost::shared_ptr< Filter<PointT> > pcl::Filter::Ptr [inherited]

Definition at line 74 of file filter.h.


Constructor & Destructor Documentation

pcl::VoxelGrid::VoxelGrid ( ) [inline]

Empty constructor.

Definition at line 152 of file voxel_grid.h.

virtual pcl::VoxelGrid::~VoxelGrid ( ) [inline, virtual]

Destructor.

Definition at line 161 of file voxel_grid.h.


Member Function Documentation

void pcl::Filter::filter ( PointCloud output) [inline, inherited]

Calls the filtering method and returns the filtered dataset in output.

Parameters:
outputthe resultant filtered point cloud dataset

Reimplemented in pcl::FilterIndices.

Definition at line 160 of file filter.h.

int pcl::VoxelGrid::getCentroidIndex ( const PointT &  p) [inline]

Returns the index in the resulting downsampled cloud of the specified point.

Note:
for efficiency, user must make sure that the saving of the leaf layout is enabled and filtering performed, and that the point is inside the grid, to avoid invalid access (or use getGridCoordinates+getCentroidIndexAt)
Parameters:
pthe point to get the index at

Definition at line 255 of file voxel_grid.h.

int pcl::VoxelGrid::getCentroidIndexAt ( const Eigen::Vector3i &  ijk,
bool  verbose = true 
) [inline]

Returns the index in the downsampled cloud corresponding to coordinates (i,j,k) in the grid (-1 if empty)

Definition at line 300 of file voxel_grid.h.

Eigen::Vector3i pcl::VoxelGrid::getDivisionMultiplier ( ) [inline]

Get the multipliers to be applied to the grid coordinates in order to find the centroid index (after filtering is performed).

Definition at line 244 of file voxel_grid.h.

bool pcl::VoxelGrid::getDownsampleAllData ( ) [inline]

Get the state of the internal downsampling parameter (true if all fields need to be downsampled, false if just XYZ).

Definition at line 210 of file voxel_grid.h.

std::string const pcl::Filter::getFilterFieldName ( ) [inline, inherited]

Get the name of the field used for filtering.

Definition at line 110 of file filter.h.

void pcl::Filter::getFilterLimits ( double &  limit_min,
double &  limit_max 
) [inline, inherited]

Get the field filter limits (min/max) set by the user.

The default values are -FLT_MAX, FLT_MAX.

Definition at line 128 of file filter.h.

void pcl::Filter::getFilterLimitsNegative ( bool &  limit_negative) [inline, inherited]

Get whether the data outside the interval (min/max) is to be returned (true) or inside (false).

Definition at line 146 of file filter.h.

bool pcl::Filter::getFilterLimitsNegative ( ) [inline, inherited]

Definition at line 151 of file filter.h.

Eigen::Vector3i pcl::VoxelGrid::getGridCoordinates ( float  x,
float  y,
float  z 
) [inline]

Returns the corresponding (i,j,k) coordinates in the grid of point (x,y,z).

Definition at line 293 of file voxel_grid.h.

std::vector<int> pcl::VoxelGrid::getLeafLayout ( ) [inline]

Returns the layout of the leafs for fast access to cells relative to current position.

Note:
position at (i-min_x) + (j-min_y)*div_x + (k-min_z)*div_x*div_y holds the index of the element at coordinates (i,j,k) in the grid (-1 if empty)

Definition at line 289 of file voxel_grid.h.

Eigen::Vector3f pcl::VoxelGrid::getLeafSize ( ) [inline]

Get the voxel grid leaf size.

Definition at line 198 of file voxel_grid.h.

Eigen::Vector3i pcl::VoxelGrid::getMaxBoxCoordinates ( ) [inline]

Get the minimum coordinates of the bounding box (after filtering is performed).

Definition at line 232 of file voxel_grid.h.

Eigen::Vector3i pcl::VoxelGrid::getMinBoxCoordinates ( ) [inline]

Get the minimum coordinates of the bounding box (after filtering is performed).

Definition at line 226 of file voxel_grid.h.

std::vector<int> pcl::VoxelGrid::getNeighborCentroidIndices ( const PointT &  reference_point,
const Eigen::MatrixXi &  relative_coordinates 
) [inline]

Returns the indices in the resulting downsampled cloud of the points at the specified grid coordinates, relative to the grid coordinates of the specified point (or -1 if the cell was empty/out of bounds).

Parameters:
reference_pointthe coordinates of the reference point (corresponding cell is allowed to be empty/out of bounds)
relative_coordinatesmatrix with the columns being the coordinates of the requested cells, relative to the reference point's cell
Note:
for efficiency, user must make sure that the saving of the leaf layout is enabled and filtering performed

Definition at line 267 of file voxel_grid.h.

Eigen::Vector3i pcl::VoxelGrid::getNrDivisions ( ) [inline]

Get the number of divisions along all 3 axes (after filtering is performed).

Definition at line 238 of file voxel_grid.h.

IndicesConstPtr const pcl::Filter::getRemovedIndices ( ) [inline, inherited]

Get the point indices being removed.

Definition at line 93 of file filter.h.

bool pcl::VoxelGrid::getSaveLeafLayout ( ) [inline]

Returns true if leaf layout information will to be saved for later access.

Definition at line 220 of file voxel_grid.h.

void pcl::VoxelGrid::setDownsampleAllData ( bool  downsample) [inline]

Set to true if all fields need to be downsampled, or false if just XYZ.

Parameters:
downsamplethe new value (true/false)

Definition at line 204 of file voxel_grid.h.

void pcl::Filter::setFilterFieldName ( const std::string &  field_name) [inline, inherited]

Provide the name of the field to be used for filtering data.

In conjunction with setFilterLimits, points having values outside this interval will be discarded.

Parameters:
field_namethe name of the field that contains values used for filtering

Definition at line 103 of file filter.h.

void pcl::Filter::setFilterLimits ( const double &  limit_min,
const double &  limit_max 
) [inline, inherited]

Set the field filter limits.

All points having field values outside this interval will be discarded.

Parameters:
limit_minthe minimum allowed field value
limit_maxthe maximum allowed field value

Definition at line 120 of file filter.h.

void pcl::Filter::setFilterLimitsNegative ( const bool  limit_negative) [inline, inherited]

Set to true if we want to return the data outside the interval specified by setFilterLimits (min, max).

Default: false.

Parameters:
limit_negativereturn data inside the interval (false) or outside (true)

Definition at line 139 of file filter.h.

void pcl::VoxelGrid::setLeafSize ( const Eigen::Vector4f &  leaf_size) [inline]

Set the voxel grid leaf size.

Parameters:
leaf_sizethe voxel grid leaf size

Definition at line 170 of file voxel_grid.h.

void pcl::VoxelGrid::setLeafSize ( float  lx,
float  ly,
float  lz 
) [inline]

Set the voxel grid leaf size.

Parameters:
lxthe leaf size for X
lythe leaf size for Y
lzthe leaf size for Z

Definition at line 186 of file voxel_grid.h.

void pcl::VoxelGrid::setSaveLeafLayout ( bool  save_leaf_layout) [inline]

Set to true if leaf layout information needs to be saved for later access.

Parameters:
save_leaf_layoutthe new value (true/false)

Definition at line 216 of file voxel_grid.h.


The documentation for this class was generated from the following files:
 All Classes Namespaces Files Functions Variables Typedefs Enumerations Enumerator Friends Defines