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/PointCloudLibrary

Estimates spin-image descriptors in the given input points. More...

#include <pcl/features/spin_image.h>

Public Types

using Ptr = shared_ptr< SpinImageEstimation< PointInT, PointNT, PointOutT > >
using ConstPtr = shared_ptr< const SpinImageEstimation< PointInT, PointNT, PointOutT > >
using PointCloudOut = typename Feature< PointInT, PointOutT >::PointCloudOut
using PointCloudN = pcl::PointCloud< PointNT >
using PointCloudNPtr = typename PointCloudN::Ptr
using PointCloudNConstPtr = typename PointCloudN::ConstPtr
using PointCloudIn = pcl::PointCloud< PointInT >
using PointCloudInPtr = typename PointCloudIn::Ptr
using PointCloudInConstPtr = typename PointCloudIn::ConstPtr
- Public Types inherited from pcl::Feature< PointInT, PointOutT >
using BaseClass = PCLBase< PointInT >
using Ptr = shared_ptr< Feature< PointInT, PointOutT > >
using ConstPtr = shared_ptr< const Feature< PointInT, PointOutT > >
using KdTree = pcl::search::Search< PointInT >
using KdTreePtr = typename KdTree::Ptr
using PointCloudIn = pcl::PointCloud< PointInT >
using PointCloudInPtr = typename PointCloudIn::Ptr
using PointCloudInConstPtr = typename PointCloudIn::ConstPtr
using PointCloudOut = pcl::PointCloud< PointOutT >
using SearchMethod = std::function< int(std::size_t, double, pcl::Indices &, std::vector< float > &)>
using SearchMethodSurface = std::function< int(const PointCloudIn &cloud, std::size_t index, double, pcl::Indices &, std::vector< float > &)>
- Public Types inherited from pcl::PCLBase< PointInT >
using PointCloud = pcl::PointCloud< PointInT >
using PointCloudPtr = typename PointCloud::Ptr
using PointCloudConstPtr = typename PointCloud::ConstPtr
using PointIndicesPtr = PointIndices::Ptr
using PointIndicesConstPtr = PointIndices::ConstPtr

Public Member Functions

SpinImageEstimation (unsigned int image_width=8, double support_angle_cos=0.0, unsigned int min_pts_neighb=0)
Constructs empty spin image estimator. More...
~SpinImageEstimation ()
Empty destructor. More...
void setImageWidth (unsigned int bin_count)
Sets spin-image resolution. More...
void setSupportAngle (double support_angle_cos)
Sets the maximum angle for the point normal to get to support region. More...
void setMinPointCountInNeighbourhood (unsigned int min_pts_neighb)
Sets minimal points count for spin image computation. More...
void setInputNormals (const PointCloudNConstPtr &normals)
Provide a pointer to the input dataset that contains the point normals of the input XYZ dataset given by setInputCloud. More...
void setRotationAxis (const PointNT &axis)
Sets single vector a rotation axis for all input points. More...
void setInputRotationAxes (const PointCloudNConstPtr &axes)
Sets array of vectors as rotation axes for input points. More...
void useNormalsAsRotationAxis ()
Sets input normals as rotation axes (default setting). More...
void setAngularDomain (bool is_angular=true)
Sets/unsets flag for angular spin-image domain. More...
void setRadialStructure (bool is_radial=true)
Sets/unsets flag for radial spin-image structure. More...
- Public Member Functions inherited from pcl::Feature< PointInT, PointOutT >
Feature ()
Empty constructor. More...
virtual ~Feature ()
Empty destructor. More...
void setSearchSurface (const PointCloudInConstPtr &cloud)
Provide a pointer to a dataset to add additional information to estimate the features for every point in the input dataset. More...
PointCloudInConstPtr getSearchSurface () const
Get a pointer to the surface point cloud dataset. More...
void setSearchMethod (const KdTreePtr &tree)
Provide a pointer to the search object. More...
KdTreePtr getSearchMethod () const
Get a pointer to the search method used. More...
double getSearchParameter () const
Get the internal search parameter. More...
void setKSearch (int k)
Set the number of k nearest neighbors to use for the feature estimation. More...
int getKSearch () const
get the number of k nearest neighbors used for the feature estimation. More...
void setRadiusSearch (double radius)
Set the sphere radius that is to be used for determining the nearest neighbors used for the feature estimation. More...
double getRadiusSearch () const
Get the sphere radius used for determining the neighbors. More...
void compute (PointCloudOut &output)
Base method for feature estimation for all points given in <setInputCloud (), setIndices ()> using the surface in setSearchSurface () and the spatial locator in setSearchMethod () More...
- Public Member Functions inherited from pcl::PCLBase< PointInT >
PCLBase ()
Empty constructor. More...
PCLBase (const PCLBase &base)
Copy constructor. More...
virtual ~PCLBase ()=default
Destructor. More...
virtual void setInputCloud (const PointCloudConstPtr &cloud)
Provide a pointer to the input dataset. More...
const PointCloudConstPtr getInputCloud () const
Get a pointer to the input point cloud dataset. More...
virtual void setIndices (const IndicesPtr &indices)
Provide a pointer to the vector of indices that represents the input data. More...
virtual void setIndices (const IndicesConstPtr &indices)
Provide a pointer to the vector of indices that represents the input data. More...
virtual void setIndices (const PointIndicesConstPtr &indices)
Provide a pointer to the vector of indices that represents the input data. More...
virtual void setIndices (std::size_t row_start, std::size_t col_start, std::size_t nb_rows, std::size_t nb_cols)
Set the indices for the points laying within an interest region of the point cloud. More...
IndicesPtr getIndices ()
Get a pointer to the vector of indices used. More...
const IndicesConstPtr getIndices () const
Get a pointer to the vector of indices used. More...
const PointInT & operator[] (std::size_t pos) const
Override PointCloud operator[] to shorten code. More...

Protected Member Functions

void computeFeature (PointCloudOut &output) override
Estimate the Spin Image descriptors at a set of points given by setInputWithNormals() using the surface in setSearchSurfaceWithNormals() and the spatial locator. More...
bool initCompute () override
initializes computations specific to spin-image. More...
Eigen::ArrayXXd computeSiForPoint (int index) const
Computes a spin-image for the point of the scan. More...
- Protected Member Functions inherited from pcl::Feature< PointInT, PointOutT >
const std::string & getClassName () const
Get a string representation of the name of this class. More...
virtual bool deinitCompute ()
This method should get called after ending the actual computation. More...
int searchForNeighbors (std::size_t index, double parameter, pcl::Indices &indices, std::vector< float > &distances) const
Search for k-nearest neighbors using the spatial locator from setSearchmethod, and the given surface from setSearchSurface. More...
int searchForNeighbors (const PointCloudIn &cloud, std::size_t index, double parameter, pcl::Indices &indices, std::vector< float > &distances) const
Search for k-nearest neighbors using the spatial locator from setSearchmethod, and the given surface from setSearchSurface. More...
- Protected Member Functions inherited from pcl::PCLBase< PointInT >
bool initCompute ()
This method should get called before starting the actual computation. More...
bool deinitCompute ()
This method should get called after finishing the actual computation. More...

Additional Inherited Members

- Protected Attributes inherited from pcl::Feature< PointInT, PointOutT >
std::string feature_name_
The feature name. More...
SearchMethodSurface search_method_surface_
The search method template for points. More...
PointCloudInConstPtr surface_
An input point cloud describing the surface that is to be used for nearest neighbors estimation. More...
KdTreePtr tree_
A pointer to the spatial search object. More...
double search_parameter_
The actual search parameter (from either search_radius_ or k_). More...
double search_radius_
The nearest neighbors search radius for each point. More...
int k_
The number of K nearest neighbors to use for each point. More...
bool fake_surface_
If no surface is given, we use the input PointCloud as the surface. More...
- Protected Attributes inherited from pcl::PCLBase< PointInT >
PointCloudConstPtr input_
The input point cloud dataset. More...
IndicesPtr indices_
A pointer to the vector of point indices to use. More...
bool use_indices_
Set to true if point indices are used. More...
bool fake_indices_
If no set of indices are given, we construct a set of fake indices that mimic the input PointCloud. More...

Detailed Description

template<typename PointInT, typename PointNT, typename PointOutT>
class pcl::SpinImageEstimation< PointInT, PointNT, PointOutT >

Estimates spin-image descriptors in the given input points.

This class represents spin image descriptor. Spin image is a histogram of point locations summed along the bins of the image. A 2D accumulator indexed by a and b is created. Next, the coordinates (a, b) are computed for a vertex in the surface mesh that is within the support of the spin image (explained below). The bin indexed by (a, b) in the accumulator is then incremented; bilinear interpolation is used to smooth the contribution of the vertex. This procedure is repeated for all vertices within the support of the spin image. The resulting accumulator can be thought of as an image; dark areas in the image correspond to bins that contain many projected points. As long as the size of the bins in the accumulator is greater than the median distance between vertices in the mesh (the definition of mesh resolution), the position of individual vertices will be averaged out during spin image generation.

Attention
The input normals given by setInputNormals have to match the input point cloud given by setInputCloud. This behavior is different than feature estimation methods that extend FeatureFromNormals, which match the normals with the search surface.

With the default parameters, pcl::Histogram<153> is a good choice for PointOutT. Of course the dimension of this descriptor must change to match the number of bins set by the parameters.

For further information please see:

  • Johnson, A. E., & Hebert, M. (1998). Surface Matching for Object Recognition in Complex 3D Scenes. Image and Vision Computing, 16, 635-651.

The class also implements radial spin images and spin-images in angular domain (or both).

Author
Roman Shapovalov, Alexander Velizhev

Definition at line 87 of file spin_image.h.

Member Typedef Documentation

ConstPtr

template<typename PointInT , typename PointNT , typename PointOutT >
using pcl::SpinImageEstimation< PointInT, PointNT, PointOutT >::ConstPtr = shared_ptr<const SpinImageEstimation<PointInT, PointNT, PointOutT> >

Definition at line 91 of file spin_image.h.

PointCloudIn

template<typename PointInT , typename PointNT , typename PointOutT >
using pcl::SpinImageEstimation< PointInT, PointNT, PointOutT >::PointCloudIn = pcl::PointCloud<PointInT>

Definition at line 107 of file spin_image.h.

PointCloudInConstPtr

template<typename PointInT , typename PointNT , typename PointOutT >
using pcl::SpinImageEstimation< PointInT, PointNT, PointOutT >::PointCloudInConstPtr = typename PointCloudIn::ConstPtr

Definition at line 109 of file spin_image.h.

PointCloudInPtr

template<typename PointInT , typename PointNT , typename PointOutT >
using pcl::SpinImageEstimation< PointInT, PointNT, PointOutT >::PointCloudInPtr = typename PointCloudIn::Ptr

Definition at line 108 of file spin_image.h.

PointCloudN

template<typename PointInT , typename PointNT , typename PointOutT >
using pcl::SpinImageEstimation< PointInT, PointNT, PointOutT >::PointCloudN = pcl::PointCloud<PointNT>

Definition at line 103 of file spin_image.h.

PointCloudNConstPtr

template<typename PointInT , typename PointNT , typename PointOutT >
using pcl::SpinImageEstimation< PointInT, PointNT, PointOutT >::PointCloudNConstPtr = typename PointCloudN::ConstPtr

Definition at line 105 of file spin_image.h.

PointCloudNPtr

template<typename PointInT , typename PointNT , typename PointOutT >
using pcl::SpinImageEstimation< PointInT, PointNT, PointOutT >::PointCloudNPtr = typename PointCloudN::Ptr

Definition at line 104 of file spin_image.h.

PointCloudOut

template<typename PointInT , typename PointNT , typename PointOutT >
using pcl::SpinImageEstimation< PointInT, PointNT, PointOutT >::PointCloudOut = typename Feature<PointInT, PointOutT>::PointCloudOut

Definition at line 101 of file spin_image.h.

Ptr

template<typename PointInT , typename PointNT , typename PointOutT >
using pcl::SpinImageEstimation< PointInT, PointNT, PointOutT >::Ptr = shared_ptr<SpinImageEstimation<PointInT, PointNT, PointOutT> >

Definition at line 90 of file spin_image.h.

Constructor & Destructor Documentation

SpinImageEstimation()

template<typename PointInT , typename PointNT , typename PointOutT >
pcl::SpinImageEstimation< PointInT, PointNT, PointOutT >::SpinImageEstimation ( unsigned int image_width = 8,
double support_angle_cos = 0.0,
unsigned int min_pts_neighb = 0
)

Constructs empty spin image estimator.

Parameters
[in] image_width spin-image resolution, number of bins along one dimension
[in] support_angle_cos minimal allowed cosine of the angle between the normals of input point and search surface point for the point to be retained in the support
[in] min_pts_neighb min number of points in the support to correctly estimate spin-image. If at some point the support contains less points, exception is thrown

Definition at line 52 of file spin_image.hpp.

References pcl::Feature< PointInT, PointOutT >::feature_name_.

~SpinImageEstimation()

template<typename PointInT , typename PointNT , typename PointOutT >
pcl::SpinImageEstimation< PointInT, PointNT, PointOutT >::~SpinImageEstimation ( )
inline

Empty destructor.

Definition at line 125 of file spin_image.h.

Member Function Documentation

computeFeature()

template<typename PointInT , typename PointNT , typename PointOutT >
void pcl::SpinImageEstimation< PointInT, PointNT, PointOutT >::computeFeature ( PointCloudOut & output )
overrideprotectedvirtual

Estimate the Spin Image descriptors at a set of points given by setInputWithNormals() using the surface in setSearchSurfaceWithNormals() and the spatial locator.

Parameters
[out] output the resultant point cloud that contains the Spin Image feature estimates

Implements pcl::Feature< PointInT, PointOutT >.

Definition at line 322 of file spin_image.hpp.

computeSiForPoint()

template<typename PointInT , typename PointNT , typename PointOutT >
Eigen::ArrayXXd pcl::SpinImageEstimation< PointInT, PointNT, PointOutT >::computeSiForPoint ( int index ) const
protected

Computes a spin-image for the point of the scan.

Parameters
[in] index the index of the reference point in the input cloud
Returns
estimated spin-image (or its variant) as a matrix

Definition at line 67 of file spin_image.hpp.

References M_PI.

initCompute()

template<typename PointInT , typename PointNT , typename PointOutT >
bool pcl::SpinImageEstimation< PointInT, PointNT, PointOutT >::initCompute
overrideprotectedvirtual

initializes computations specific to spin-image.

Returns
true iff input data and initialization are correct

Reimplemented from pcl::Feature< PointInT, PointOutT >.

Definition at line 237 of file spin_image.hpp.

References pcl::Feature< PointInT, PointOutT >::deinitCompute().

setAngularDomain()

template<typename PointInT , typename PointNT , typename PointOutT >
void pcl::SpinImageEstimation< PointInT, PointNT, PointOutT >::setAngularDomain ( bool is_angular = true )
inline

Sets/unsets flag for angular spin-image domain.

Angular spin-image differs from the vanilla one in the way that not the points are collected in the bins but the angles between their normals and the normal to the reference point. For further information please see Endres, F., Plagemann, C., Stachniss, C., & Burgard, W. (2009). Unsupervised Discovery of Object Classes from Range Data using Latent Dirichlet Allocation. In Robotics: Science and Systems. Seattle, USA.

Parameters
[in] is_angular true for angular domain, false for point domain

Definition at line 230 of file spin_image.h.

setImageWidth()

template<typename PointInT , typename PointNT , typename PointOutT >
void pcl::SpinImageEstimation< PointInT, PointNT, PointOutT >::setImageWidth ( unsigned int bin_count )
inline

Sets spin-image resolution.

Parameters
[in] bin_count spin-image resolution, number of bins along one dimension

Definition at line 132 of file spin_image.h.

setInputNormals()

template<typename PointInT , typename PointNT , typename PointOutT >
void pcl::SpinImageEstimation< PointInT, PointNT, PointOutT >::setInputNormals ( const PointCloudNConstPtr & normals )
inline

Provide a pointer to the input dataset that contains the point normals of the input XYZ dataset given by setInputCloud.

Attention
The input normals given by setInputNormals have to match the input point cloud given by setInputCloud. This behavior is different than feature estimation methods that extend FeatureFromNormals, which match the normals with the search surface.
Parameters
[in] normals the const boost shared pointer to a PointCloud of normals. By convention, L2 norm of each normal should be 1.

Definition at line 177 of file spin_image.h.

setInputRotationAxes()

template<typename PointInT , typename PointNT , typename PointOutT >
void pcl::SpinImageEstimation< PointInT, PointNT, PointOutT >::setInputRotationAxes ( const PointCloudNConstPtr & axes )
inline

Sets array of vectors as rotation axes for input points.

Useful e.g. when one wants to use tangents instead of normals as rotation axes

Parameters
[in] axes unit-length vectors that serves as rotation axes for the corresponding input points' reference frames

Definition at line 202 of file spin_image.h.

setMinPointCountInNeighbourhood()

template<typename PointInT , typename PointNT , typename PointOutT >
void pcl::SpinImageEstimation< PointInT, PointNT, PointOutT >::setMinPointCountInNeighbourhood ( unsigned int min_pts_neighb )
inline

Sets minimal points count for spin image computation.

Parameters
[in] min_pts_neighb min number of points in the support to correctly estimate spin-image. If at some point the support contains less points, exception is thrown

Definition at line 161 of file spin_image.h.

setRadialStructure()

template<typename PointInT , typename PointNT , typename PointOutT >
void pcl::SpinImageEstimation< PointInT, PointNT, PointOutT >::setRadialStructure ( bool is_radial = true )
inline

Sets/unsets flag for radial spin-image structure.

Instead of rectangular coordinate system for reference frame polar coordinates are used. Binning is done depending on the distance and inclination angle from the reference point

Parameters
[in] is_radial true for radial spin-image structure, false for rectangular

Definition at line 240 of file spin_image.h.

setRotationAxis()

template<typename PointInT , typename PointNT , typename PointOutT >
void pcl::SpinImageEstimation< PointInT, PointNT, PointOutT >::setRotationAxis ( const PointNT & axis )
inline

Sets single vector a rotation axis for all input points.

It could be useful e.g. when the vertical axis is known.

Parameters
[in] axis unit-length vector that serves as rotation axis for reference frame

Definition at line 188 of file spin_image.h.

setSupportAngle()

template<typename PointInT , typename PointNT , typename PointOutT >
void pcl::SpinImageEstimation< PointInT, PointNT, PointOutT >::setSupportAngle ( double support_angle_cos )
inline

Sets the maximum angle for the point normal to get to support region.

Parameters
[in] support_angle_cos minimal allowed cosine of the angle between the normals of input point and search surface point for the point to be retained in the support

Definition at line 144 of file spin_image.h.

useNormalsAsRotationAxis()

template<typename PointInT , typename PointNT , typename PointOutT >
void pcl::SpinImageEstimation< PointInT, PointNT, PointOutT >::useNormalsAsRotationAxis ( )
inline

Sets input normals as rotation axes (default setting).

Definition at line 212 of file spin_image.h.


The documentation for this class was generated from the following files:

© 2009–2012, Willow Garage, Inc.
© 2012–, Open Perception, Inc.
Licensed under the BSD License.
https://pointclouds.org/documentation/classpcl_1_1_spin_image_estimation.html