PrimitivesRansac Class Reference

Extract primitives from point clouds using RANSAC.Usage example: More...

#include <easy3d/algo/point_cloud_ransac.h>

Classes
struct	CylinderPrim
	Information about a cylinder primitive. More...
struct	PlanePrim
	Information about a plane primitive. More...

Public Types
enum	PrimType {   PLANE = 0 , SPHERE = 1 , CYLINDER = 2 , CONE = 3 ,   TORUS = 4 , UNKNOWN = -1 }
	The primitive types that can be extracted. More...

Public Member Functions
void	add_primitive_type (PrimType t)
	Set up the primitive types to be extracted.
void	remove_primitive_type (PrimType t)
	Exclude a primitive types to be extracted.
int	detect (PointCloud *cloud, unsigned int min_support=1000, float dist_threshold=0.005f, float bitmap_resolution=0.02f, float normal_threshold=0.8f, float overlook_probability=0.001f)
	Extract primitives from a point cloud.
int	detect (PointCloud *cloud, const std::vector< int > &vertices, unsigned int min_support=1000, float dist_threshold=0.005f, float bitmap_resolution=0.02f, float normal_threshold=0.8f, float overlook_probability=0.001f)
	Extract primitives from a subset of a point cloud.
const std::vector< PlanePrim > &	get_planes () const
	Get the detected planes.
const std::vector< CylinderPrim > &	get_cylinders () const

Detailed Description

Extract primitives from point clouds using RANSAC.

Usage example:

Todo: (1) redesign the APIs (2) allow all five types of primitives (and support parameters)

PrimitivesRansac ransac;
ransac.add_primitive_type(PrimitivesRansac::PLANE);
int num = ransac.detect(cloud);

Examples

Tutorial_703_Cloud_PlaneExtraction/main.cpp.

Member Enumeration Documentation

PrimType

enum PrimType

The primitive types that can be extracted.

Enumerator
PLANE	Plane primitive.
SPHERE	Sphere primitive.
CYLINDER	Cylinder primitive.
CONE	Cone primitive.
TORUS	Torus primitive.
UNKNOWN	Unknown primitive.

Member Function Documentation

add_primitive_type()

void add_primitive_type

(

PrimType

t

)

Set up the primitive types to be extracted.

This is done by adding the interested primitive types one by one.

Examples

Tutorial_703_Cloud_PlaneExtraction/main.cpp.

detect() [1/2]

int detect	(	PointCloud *	cloud,
		const std::vector< int > &	vertices,
		unsigned int	min_support = 1000,
		float	dist_threshold = 0.005f,
		float	bitmap_resolution = 0.02f,
		float	normal_threshold = 0.8f,
		float	overlook_probability = 0.001f )

Extract primitives from a subset of a point cloud.

The extracted primitives are stored as per-vertex properties:

• "v:primitive_type" (one of PLANE, SPHERE, CYLINDER, CONE, TORUS, and UNKNOWN)
• "v:primitive_index" (-1, 0, 1, 2...). -1 meaning a vertex does not belong to any primitive (thus its primitive_type must be UNKNOWN). In addition to the primitive information stored as properties, the parameters of the detected primitives can also be queried using this functions.

  See also

  get_planes, get_cylinders.

  Parameters

  cloud	The input point cloud.
  vertices	The indices of the subset of the input point cloud.
  min_support	The minimal number of points required for a primitive.
  dist_threshold	The distance threshold, defined relative to the bounding box's max dimension.
  bitmap_resolution	The bitmap resolution, defined relative to the bounding box width.
  normal_threshold	The cosine of the maximal normal deviation.
  overlook_probability	The probability with which a primitive is overlooked.

  Returns

  The number of extracted primitives.

detect() [2/2]

int detect	(	PointCloud *	cloud,
		unsigned int	min_support = 1000,
		float	dist_threshold = 0.005f,
		float	bitmap_resolution = 0.02f,
		float	normal_threshold = 0.8f,
		float	overlook_probability = 0.001f )

Extract primitives from a point cloud.

The extracted primitives are stored as properties:

• "v:primitive_type" (one of PLANE, SPHERE, CYLINDER, CONE, TORUS, and UNKNOWN)
• "v:primitive_index" (-1, 0, 1, 2...). -1 meaning a vertex does not belong to any primitive (thus its primitive_type must be UNKNOWN).

  Parameters

  cloud	The input point cloud.
  min_support	The minimal number of points required for a primitive.
  dist_threshold	The distance threshold, defined relative to the bounding box's max dimension.
  bitmap_resolution	The bitmap resolution, defined relative to the bounding box width.
  normal_threshold	The cosine of the maximal normal deviation.
  overlook_probability	The probability with which a primitive is overlooked.

  Returns

  The number of extracted primitives.

Examples

Tutorial_703_Cloud_PlaneExtraction/main.cpp.

get_cylinders()

const std::vector< CylinderPrim > & get_cylinders ( ) const

inline

Get the detected cylinders.

remove_primitive_type()

void remove_primitive_type

(

PrimType

t

)

Exclude a primitive types to be extracted.

This is done by removing the primitive type from the existing list.

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

• G:/3_code/Easy3D/easy3d/algo/point_cloud_ransac.h
• G:/3_code/Easy3D/easy3d/algo/point_cloud_ransac.cpp