SIFTKeypoint detects the Scale Invariant Feature Transform keypoints for a given point cloud dataset containing points and intensity. More...

#include <pcl/keypoints/sift_keypoint.h>

Inheritance diagram for pcl::SIFTKeypoint< PointInT, PointOutT >:

Collaboration diagram for pcl::SIFTKeypoint< PointInT, PointOutT >:

Public Types
using	Ptr = shared_ptr< SIFTKeypoint< PointInT, PointOutT > >

using	ConstPtr = shared_ptr< const SIFTKeypoint< PointInT, PointOutT > >

using	PointCloudIn = typename Keypoint< PointInT, PointOutT >::PointCloudIn

using	PointCloudOut = typename Keypoint< PointInT, PointOutT >::PointCloudOut

using	KdTree = typename Keypoint< PointInT, PointOutT >::KdTree

Public Types inherited from pcl::Keypoint< PointInT, PointOutT >
using	Ptr = shared_ptr< Keypoint< PointInT, PointOutT > >

using	ConstPtr = shared_ptr< const Keypoint< PointInT, PointOutT > >

using	BaseClass = PCLBase< PointInT >

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(pcl::index_t, double, pcl::Indices &, std::vector< float > &)>

using	SearchMethodSurface = std::function< int(const PointCloudIn &cloud, pcl::index_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
	SIFTKeypoint ()
	Empty constructor. More...

void	setScales (float min_scale, int nr_octaves, int nr_scales_per_octave)
	Specify the range of scales over which to search for keypoints. More...

void	setMinimumContrast (float min_contrast)
	Provide a threshold to limit detection of keypoints without sufficient contrast. More...

Public Member Functions inherited from pcl::Keypoint< PointInT, PointOutT >
	Keypoint ()=default

	Keypoint ()
	Empty constructor. More...

void	harrisCorner (PointInT &output, PointInT &input, const float sigma_d, const float sigma_i, const float alpha, const float thresh)

void	hessianBlob (PointInT &output, PointInT &input, const float sigma, bool SCALE)

void	hessianBlob (PointInT &output, PointInT &input, const float start_scale, const float scaling_factor, const int num_scales)

void	imageElementMultiply (PointInT &output, PointInT &input1, PointInT &input2)

	~Keypoint () override=default
	Empty destructor. More...

virtual void	setSearchSurface (const PointCloudInConstPtr &cloud)
	Provide a pointer to the input dataset that we need to estimate features at every point for. More...

PointCloudInConstPtr	getSearchSurface ()
	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 ()
	Get a pointer to the search method used. More...

double	getSearchParameter ()
	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 ()
	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 key point detection. More...

double	getRadiusSearch ()
	Get the sphere radius used for determining the neighbors. More...

pcl::PointIndicesConstPtr	getKeypointsIndices ()

void	compute (PointCloudOut &output)
	Base method for key point detection for all points given in <setInputCloud (), setIndices ()> using the surface in setSearchSurface () and the spatial locator in setSearchMethod () More...

int	searchForNeighbors (pcl::index_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...

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...

PointCloudConstPtr const	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...

IndicesConstPtr const	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
bool	initCompute () override

void	detectKeypoints (PointCloudOut &output) override
	Detect the SIFT keypoints for a set of points given in setInputCloud () using the spatial locator in setSearchMethod (). More...

Protected Member Functions inherited from pcl::Keypoint< PointInT, PointOutT >
const std::string &	getClassName () const
	Get a string representation of the name of this class. More...

virtual void	detectKeypoints (PointCloudOut &output)=0
	Abstract key point detection method. 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::Keypoint< PointInT, PointOutT >
std::string	name_
	The key point detection method's name. More...

SearchMethod	search_method_
	The search method template for indices. 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 (casted 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...

pcl::PointIndicesPtr	keypoints_indices_
	Indices of the keypoints in the input cloud. 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 PointOutT>
class pcl::SIFTKeypoint< PointInT, PointOutT >

SIFTKeypoint detects the Scale Invariant Feature Transform keypoints for a given point cloud dataset containing points and intensity.

This implementation adapts the original algorithm from images to point clouds.

For more information about the image-based SIFT interest operator, see:

David G. Lowe, "Distinctive image features from scale-invariant keypoints," International Journal of Computer Vision, 60, 2 (2004), pp. 91-110.

Author: Michael Dixon

Definition at line 93 of file sift_keypoint.h.

Member Typedef Documentation

◆ ConstPtr

template<typename PointInT , typename PointOutT >

using pcl::SIFTKeypoint< PointInT, PointOutT >::ConstPtr = shared_ptr<const SIFTKeypoint<PointInT, PointOutT> >

Definition at line 97 of file sift_keypoint.h.

◆ KdTree

template<typename PointInT , typename PointOutT >

using pcl::SIFTKeypoint< PointInT, PointOutT >::KdTree = typename Keypoint<PointInT, PointOutT>::KdTree

Definition at line 101 of file sift_keypoint.h.

◆ PointCloudIn

template<typename PointInT , typename PointOutT >

using pcl::SIFTKeypoint< PointInT, PointOutT >::PointCloudIn = typename Keypoint<PointInT, PointOutT>::PointCloudIn

Definition at line 99 of file sift_keypoint.h.

◆ PointCloudOut

template<typename PointInT , typename PointOutT >

using pcl::SIFTKeypoint< PointInT, PointOutT >::PointCloudOut = typename Keypoint<PointInT, PointOutT>::PointCloudOut

Definition at line 100 of file sift_keypoint.h.

◆ Ptr

template<typename PointInT , typename PointOutT >

using pcl::SIFTKeypoint< PointInT, PointOutT >::Ptr = shared_ptr<SIFTKeypoint<PointInT, PointOutT> >

Definition at line 96 of file sift_keypoint.h.

Constructor & Destructor Documentation

◆ SIFTKeypoint()

template<typename PointInT , typename PointOutT >

pcl::SIFTKeypoint< PointInT, PointOutT >::SIFTKeypoint ( )

inline

Empty constructor.

Definition at line 111 of file sift_keypoint.h.

References pcl::Keypoint< PointInT, PointOutT >::name_.

Member Function Documentation

◆ detectKeypoints()

template<typename PointInT , typename PointOutT >

void pcl::SIFTKeypoint< PointInT, PointOutT >::detectKeypoints ( PointCloudOut & output )

overrideprotected

Detect the SIFT keypoints for a set of points given in setInputCloud () using the spatial locator in setSearchMethod ().

Parameters

output the resultant cloud of keypoints

Definition at line 99 of file sift_keypoint.hpp.

References pcl::Filter< PointT >::filter(), pcl::PCLBase< PointT >::setInputCloud(), pcl::VoxelGrid< PointT >::setLeafSize(), and pcl::PointCloud< PointT >::size().

◆ initCompute()

template<typename PointInT , typename PointOutT >

bool pcl::SIFTKeypoint< PointInT, PointOutT >::initCompute

overrideprotectedvirtual

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

Definition at line 65 of file sift_keypoint.hpp.

◆ setMinimumContrast()

template<typename PointInT , typename PointOutT >

void pcl::SIFTKeypoint< PointInT, PointOutT >::setMinimumContrast ( float min_contrast )

Provide a threshold to limit detection of keypoints without sufficient contrast.

Parameters

min_contrast the minimum contrast required for detection

Definition at line 58 of file sift_keypoint.hpp.

◆ setScales()

template<typename PointInT , typename PointOutT >

void pcl::SIFTKeypoint< PointInT, PointOutT >::setScales	(	float	min_scale,
		int	nr_octaves,
		int	nr_scales_per_octave
	)

Specify the range of scales over which to search for keypoints.

Parameters

min_scale	the standard deviation of the smallest scale in the scale space
nr_octaves	the number of octaves (i.e. doublings of scale) to compute
nr_scales_per_octave	the number of scales to compute within each octave

Definition at line 48 of file sift_keypoint.hpp.

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

pcl/keypoints/sift_keypoint.h
pcl/keypoints/impl/sift_keypoint.hpp

Public Types

Public Member Functions

Protected Member Functions

Additional Inherited Members

Detailed Description

template<typename PointInT, typename PointOutT> class pcl::SIFTKeypoint< PointInT, PointOutT >

Member Typedef Documentation

◆ ConstPtr

◆ KdTree

◆ PointCloudIn

◆ PointCloudOut

◆ Ptr

Constructor & Destructor Documentation

◆ SIFTKeypoint()

Member Function Documentation

◆ detectKeypoints()

◆ initCompute()

◆ setMinimumContrast()

◆ setScales()

template<typename PointInT, typename PointOutT>
class pcl::SIFTKeypoint< PointInT, PointOutT >