Base for classes which locate feature points. More...

#include <mfpf_point_finder.h>

Inheritance diagram for mfpf_point_finder:

Public Member Functions
	mfpf_point_finder ()
	Dflt ctor.
virtual	~mfpf_point_finder ()
	Destructor.
virtual void	set_step_size (double)
	Size of step between sample points.
double	step_size () const
	Size of step between sample points.
virtual void	set_search_area (unsigned ni, unsigned nj)
	Define search region size.
void	set_angle_range (unsigned nA, double dA)
	Define angle search parameters.
void	set_scale_range (unsigned ns, double ds)
	Define scale search parameters.
int	search_ni () const
	Number of points either side of centre to search along i.
int	search_nj () const
	Number of points either side of centre to search along j.
virtual bool	set_model (const vcl_vector< double > &v)
	Set model to a new value when provided with a vector.
virtual unsigned	model_dim ()
	Number of dimensions in the model.
virtual double	radius () const =0
	Radius of circle containing modelled region (in model frame units).
virtual void	get_sample_vector (const vimt_image_2d_of< float > &image, const vgl_point_2d< double > &p, const vgl_vector_2d< double > &u, vcl_vector< double > &v)
	Get sample of region around specified point in image.
virtual double	evaluate (const vimt_image_2d_of< float > &image, const vgl_point_2d< double > &p, const vgl_vector_2d< double > &u)=0
	Evaluate match at p, using u to define scale and orientation.
virtual void	evaluate_region (const vimt_image_2d_of< float > &image, const vgl_point_2d< double > &p, const vgl_vector_2d< double > &u, vimt_image_2d_of< double > &response)=0
	Evaluate match at in a region around p.
virtual double	search_one_pose (const vimt_image_2d_of< float > &image, const vgl_point_2d< double > &p, const vgl_vector_2d< double > &u, vgl_point_2d< double > &new_p)=0
	Search given image around p, using u to define scale and angle.
virtual double	search_one_pose_with_opt (const vimt_image_2d_of< float > &image, const vgl_point_2d< double > &p, const vgl_vector_2d< double > &u, vgl_point_2d< double > &new_p)
	Search given image around p, using u to define scale and angle.
virtual double	search (const vimt_image_2d_of< float > &image, const vgl_point_2d< double > &p, const vgl_vector_2d< double > &u, vgl_point_2d< double > &new_p, vgl_vector_2d< double > &new_u)
	Search given image around p, using u to define scale and orientation.
virtual double	search_with_opt (const vimt_image_2d_of< float > &image, const vgl_point_2d< double > &p, const vgl_vector_2d< double > &u, vgl_point_2d< double > &new_p, vgl_vector_2d< double > &new_u)
	Search given image around p, using u to define scale and orientation.
virtual void	grid_search_one_pose (const vimt_image_2d_of< float > &image, const vgl_point_2d< double > &p, const vgl_vector_2d< double > &u, vcl_vector< mfpf_pose > &pts, vcl_vector< double > &fit)
	Search for local optima around given point/scale/angle.
virtual void	multi_search_one_pose (const vimt_image_2d_of< float > &image, const vgl_point_2d< double > &p, const vgl_vector_2d< double > &u, vcl_vector< mfpf_pose > &pts, vcl_vector< double > &fit)
	Search for local optima around given point/scale/angle.
virtual void	grid_search (const vimt_image_2d_of< float > &image, const vgl_point_2d< double > &p, const vgl_vector_2d< double > &u, vcl_vector< mfpf_pose > &poses, vcl_vector< double > &fit)
	Search for local optima around given point/scale/angle.
virtual void	multi_search (const vimt_image_2d_of< float > &image, const vgl_point_2d< double > &p, const vgl_vector_2d< double > &u, vcl_vector< mfpf_pose > &poses, vcl_vector< double > &fits)
	Search for local optima around given point/scale/angle.
virtual void	refine_match (const vimt_image_2d_of< float > &image, vgl_point_2d< double > &p, vgl_vector_2d< double > &u, double &fit)
	Perform local optimisation to refine position,scale and angle.
virtual bool	overlap (const mfpf_pose &pose1, const mfpf_pose &pose2) const
	Return true if modelled regions at pose1 and pose2 overlap.
virtual void	get_outline (vcl_vector< vgl_point_2d< double > > &pts) const =0
	Generate points in ref frame that represent boundary.
virtual void	aligned_bounding_box (const mfpf_pose &pose, mfpf_pose &box_pose, double &wi, double &wj) const
	Computes the aligned bounding box for feature with given pose.
virtual void	get_image_of_model (vimt_image_2d_of< vxl_byte > &image) const
	Create an image summarising the average model (where possible).
unsigned	image_level (const mfpf_pose &pose, const vimt_image_pyramid &im_pyr) const
	Select best level for searching around pose.
short	version_no () const
	Version number for I/O.
virtual vcl_string	is_a () const
	Name of the class.
virtual mfpf_point_finder *	clone () const =0
	Create a copy on the heap and return base class pointer.
virtual void	print_summary (vcl_ostream &os) const
	Print class to os.
virtual void	b_write (vsl_b_ostream &bfs) const
	Save class to binary file stream.
virtual void	b_read (vsl_b_istream &bfs)
	Load class from binary file stream.
Protected Member Functions
bool	base_equality (const mfpf_point_finder &pf) const
	Return true if base class parameters are the same in pf.
Protected Attributes
double	step_size_
	Size of step between sample points.
int	search_ni_
	Number of points either side of centre to search.
int	search_nj_
	Number of points either side of centre to search.
unsigned	nA_
	Define N. angles (ie try at A+idA, i in [-nA,+nA]).
double	dA_
	Angle step size (ie try at A+idA, i in [-nA,+nA]).
unsigned	ns_
	Number of scales to try at.
double	ds_
	Scaling factor (ie try at ((ds)^i), i in [-ns,+ns].

Detailed Description

Base for classes which locate feature points.

The object will be set up by an associated mfpf_point_finder_builder object

Definition at line 24 of file mfpf_point_finder.h.

Constructor & Destructor Documentation

mfpf_point_finder::mfpf_point_finder ( )

Dflt ctor.

Definition at line 120 of file mfpf_point_finder.cxx.

mfpf_point_finder::~mfpf_point_finder ( ) [virtual]

Destructor.

Definition at line 131 of file mfpf_point_finder.cxx.

Member Function Documentation

void mfpf_point_finder::aligned_bounding_box	(	const mfpf_pose &	pose,
		mfpf_pose &	box_pose,
		double &	wi,
		double &	wj
	)		const `[virtual]`

Computes the aligned bounding box for feature with given pose.

On exit box_pose.p() gives the centre, corners are given by box_pose(+/-0.5*wi, +/-0.5*wj).

Definition at line 600 of file mfpf_point_finder.cxx.

void mfpf_point_finder::b_read ( vsl_b_istream & bfs ) [virtual]

Load class from binary file stream.

Reimplemented in mfpf_region_finder, mfpf_grad_corr2d, mfpf_hog_box_finder, mfpf_region_pdf, mfpf_norm_corr2d, mfpf_norm_corr1d, mfpf_profile_pdf, mfpf_edge_finder, and mfpf_max_finder.

Definition at line 683 of file mfpf_point_finder.cxx.

void mfpf_point_finder::b_write ( vsl_b_ostream & bfs ) const [virtual]

Save class to binary file stream.

Reimplemented in mfpf_region_finder, mfpf_grad_corr2d, mfpf_hog_box_finder, mfpf_region_pdf, mfpf_norm_corr2d, mfpf_norm_corr1d, mfpf_profile_pdf, mfpf_edge_finder, and mfpf_max_finder.

Definition at line 667 of file mfpf_point_finder.cxx.

bool mfpf_point_finder::base_equality ( const mfpf_point_finder & pf ) const [protected]

Return true if base class parameters are the same in pf.

Definition at line 627 of file mfpf_point_finder.cxx.

virtual mfpf_point_finder* mfpf_point_finder::clone ( ) const [pure virtual]

Create a copy on the heap and return base class pointer.

Implemented in mfpf_region_finder, mfpf_grad_corr2d, mfpf_hog_box_finder, mfpf_region_pdf, mfpf_norm_corr2d, mfpf_norm_corr1d, mfpf_profile_pdf, mfpf_edge_finder, and mfpf_max_finder.

virtual double mfpf_point_finder::evaluate	(	const vimt_image_2d_of< float > &	image,
		const vgl_point_2d< double > &	p,
		const vgl_vector_2d< double > &	u
	)		`[pure virtual]`

Evaluate match at p, using u to define scale and orientation.

Returns a quality of fit measure at the point (the smaller the better).

Implemented in mfpf_region_finder, mfpf_grad_corr2d, mfpf_hog_box_finder, mfpf_region_pdf, mfpf_norm_corr2d, mfpf_norm_corr1d, mfpf_profile_pdf, mfpf_edge_finder, and mfpf_max_finder.

virtual void mfpf_point_finder::evaluate_region	(	const vimt_image_2d_of< float > &	image,
		const vgl_point_2d< double > &	p,
		const vgl_vector_2d< double > &	u,
		vimt_image_2d_of< double > &	response
	)		`[pure virtual]`

Evaluate match at in a region around p.

Returns a quality of fit at a set of positions. response image (whose size and transform is set inside the function), indicates the points at which the function was evaluated. response(i,j) is the fit at the point response.world2im().inverse()(i,j). The world2im() transformation may be affine.

Implemented in mfpf_region_finder, mfpf_grad_corr2d, mfpf_hog_box_finder, mfpf_region_pdf, mfpf_norm_corr2d, mfpf_norm_corr1d, mfpf_profile_pdf, mfpf_edge_finder, and mfpf_max_finder.

void mfpf_point_finder::get_image_of_model ( vimt_image_2d_of< vxl_byte > & image ) const [virtual]

Create an image summarising the average model (where possible).

For instance, creates an image of the mean template used for search. image.world2im() gives mapping from reference frame into raw image co-ords (including the step size). Default implementation does nothing - returns an empty image.

For instance, creates an image of the mean template used for search. Default implementation does nothing - returns an empty image.

Reimplemented in mfpf_region_finder, mfpf_grad_corr2d, mfpf_region_pdf, and mfpf_norm_corr2d.

Definition at line 566 of file mfpf_point_finder.cxx.

virtual void mfpf_point_finder::get_outline ( vcl_vector< vgl_point_2d< double > > & pts ) const [pure virtual]

Generate points in ref frame that represent boundary.

Points of a contour around the shape. Used for display purposes. Join the points with an open contour to get a representation.

Implemented in mfpf_region_finder, mfpf_grad_corr2d, mfpf_hog_box_finder, mfpf_region_pdf, mfpf_norm_corr2d, mfpf_norm_corr1d, mfpf_profile_pdf, mfpf_edge_finder, and mfpf_max_finder.

void mfpf_point_finder::get_sample_vector	(	const vimt_image_2d_of< float > &	image,
		const vgl_point_2d< double > &	p,
		const vgl_vector_2d< double > &	u,
		vcl_vector< double > &	v
	)		`[virtual]`

Get sample of region around specified point in image.

Reimplemented in mfpf_grad_corr2d, and mfpf_norm_corr2d.

Definition at line 177 of file mfpf_point_finder.cxx.

void mfpf_point_finder::grid_search	(	const vimt_image_2d_of< float > &	image,
		const vgl_point_2d< double > &	p,
		const vgl_vector_2d< double > &	u,
		vcl_vector< mfpf_pose > &	pts,
		vcl_vector< double > &	fit
	)		`[virtual]`

Search for local optima around given point/scale/angle.

For each angle and scale (defined by internal nA,dA,ns,ds) search in a grid around p (defined by search_ni and search_nj). Find local minima on this grid and return them in poses. Responses lie on grid in (x,y,ds,dA)

Note that an object in an image may lead to multiple responses, one at each scale and angle near to the optima. Thus the poses defined in pts should be further refined to eliminate such multiple responses.

For each angle and scale (defined by internal nA,dA,ns,ds) search in a grid around p (defined by search_ni and search_nj). Find local minima on this grid and return them in pts.

Note that an object in an image may lead to multiple responses, one at each scale and angle near to the optima. Thus the poses defined in pts should be further refined to eliminate such multiple responses.

Definition at line 452 of file mfpf_point_finder.cxx.

void mfpf_point_finder::grid_search_one_pose	(	const vimt_image_2d_of< float > &	image,
		const vgl_point_2d< double > &	p,
		const vgl_vector_2d< double > &	u,
		vcl_vector< mfpf_pose > &	pts,
		vcl_vector< double > &	fit
	)		`[virtual]`

Search for local optima around given point/scale/angle.

Search in a grid around p (defined by search_ni and search_nj). Find local minima on this grid and return append each to pts. Note: pts is not resized, so empty beforehand if necessary.

Search in a grid around p (defined by search_ni and search_nj). Find local minima on this grid and return them in pts.

Definition at line 337 of file mfpf_point_finder.cxx.

unsigned mfpf_point_finder::image_level	(	const mfpf_pose &	pose,
		const vimt_image_pyramid &	im_pyr
	)		const

Select best level for searching around pose.

Select best level for searching around pose with finder.

Selects pyramid level with pixel sizes best matching the model pixel size at given pose.

Definition at line 575 of file mfpf_point_finder.cxx.

vcl_string mfpf_point_finder::is_a ( ) const [virtual]

Name of the class.

Reimplemented in mfpf_region_finder, mfpf_grad_corr2d, mfpf_hog_box_finder, mfpf_region_pdf, mfpf_norm_corr2d, mfpf_norm_corr1d, mfpf_profile_pdf, mfpf_edge_finder, and mfpf_max_finder.

Definition at line 711 of file mfpf_point_finder.cxx.

unsigned mfpf_point_finder::model_dim ( ) [virtual]

Number of dimensions in the model.

Number of dimensions in the model (return 0 by default).

Reimplemented in mfpf_grad_corr2d, mfpf_norm_corr2d, and mfpf_norm_corr1d.

Definition at line 171 of file mfpf_point_finder.cxx.

void mfpf_point_finder::multi_search	(	const vimt_image_2d_of< float > &	image,
		const vgl_point_2d< double > &	p,
		const vgl_vector_2d< double > &	u,
		vcl_vector< mfpf_pose > &	poses,
		vcl_vector< double > &	fits
	)		`[virtual]`

Search for local optima around given point/scale/angle.

For each angle and scale (defined by internal nA,dA,ns,ds) search in a grid around p (defined by search_ni and search_nj). Find local minima on this grid. Sub-grid estimation using parabolic fitting included. poses[i] defines result i, with corresponding fit fits[i]

Note that an object in an image may lead to multiple responses, one at each scale and angle near to the optima. Thus the poses defined in pts should be further refined to eliminate such multiple responses.

Definition at line 493 of file mfpf_point_finder.cxx.

void mfpf_point_finder::multi_search_one_pose	(	const vimt_image_2d_of< float > &	image,
		const vgl_point_2d< double > &	p0,
		const vgl_vector_2d< double > &	u,
		vcl_vector< mfpf_pose > &	pts,
		vcl_vector< double > &	fit
	)		`[virtual]`

Search for local optima around given point/scale/angle.

Search in a grid around p (defined by search_ni and search_nj). Find local minima on this grid. Perform single sub-grid optimisation by fitting a parabola in x and y and testing resulting point. Append each to pts. Note: pts is not resized, so empty beforehand if necessary.

Definition at line 367 of file mfpf_point_finder.cxx.

bool mfpf_point_finder::overlap	(	const mfpf_pose &	pose1,
		const mfpf_pose &	pose2
	)		const `[virtual]`

Return true if modelled regions at pose1 and pose2 overlap.

Reimplemented in mfpf_region_finder, mfpf_grad_corr2d, mfpf_hog_box_finder, mfpf_region_pdf, and mfpf_norm_corr2d.

Definition at line 591 of file mfpf_point_finder.cxx.

void mfpf_point_finder::print_summary ( vcl_ostream & os ) const [virtual]

Print class to os.

Reimplemented in mfpf_region_finder, mfpf_grad_corr2d, mfpf_hog_box_finder, mfpf_region_pdf, mfpf_norm_corr2d, mfpf_norm_corr1d, mfpf_profile_pdf, mfpf_edge_finder, and mfpf_max_finder.

Definition at line 644 of file mfpf_point_finder.cxx.

virtual double mfpf_point_finder::radius ( ) const [pure virtual]

Radius of circle containing modelled region (in model frame units).

Radius in world units given by step_size()*radius()

Implemented in mfpf_grad_corr2d, mfpf_region_finder, mfpf_hog_box_finder, mfpf_norm_corr2d, mfpf_region_pdf, mfpf_norm_corr1d, mfpf_profile_pdf, mfpf_edge_finder, and mfpf_max_finder.

void mfpf_point_finder::refine_match	(	const vimt_image_2d_of< float > &	image,
		vgl_point_2d< double > &	p,
		vgl_vector_2d< double > &	u,
		double &	fit
	)		`[virtual]`

Perform local optimisation to refine position,scale and angle.

On input fit is match at p,u. On exit p,u and fit are updated. Baseclass implementation uses simplex optimisation.

Definition at line 526 of file mfpf_point_finder.cxx.

double mfpf_point_finder::search	(	const vimt_image_2d_of< float > &	image,
		const vgl_point_2d< double > &	p,
		const vgl_vector_2d< double > &	u,
		vgl_point_2d< double > &	new_p,
		vgl_vector_2d< double > &	new_u
	)		`[virtual]`

Search given image around p, using u to define scale and orientation.

On exit, new_p and new_u define position, scale and orientation of the best nearby match. Returns a quality of fit measure at that point (the smaller the better).

Default implementation calls search_one_pose(...) at multiple angles and scales. Result will be at a grid position and one of the given angle/scales. True optima can then be found by further optimisation of the point.

On exit, new_p and new_u define position, scale and orientation of the best nearby match. Returns a quality of fit measure at that point (the smaller the better).

Definition at line 241 of file mfpf_point_finder.cxx.

int mfpf_point_finder::search_ni ( ) const [inline]

Number of points either side of centre to search along i.

Definition at line 76 of file mfpf_point_finder.h.

int mfpf_point_finder::search_nj ( ) const [inline]

Number of points either side of centre to search along j.

Definition at line 79 of file mfpf_point_finder.h.

virtual double mfpf_point_finder::search_one_pose	(	const vimt_image_2d_of< float > &	image,
		const vgl_point_2d< double > &	p,
		const vgl_vector_2d< double > &	u,
		vgl_point_2d< double > &	new_p
	)		`[pure virtual]`

Search given image around p, using u to define scale and angle.

On exit, new_p defines position of the best nearby match. Returns a quality of fit measure at that point (the smaller the better).

Implemented in mfpf_region_finder, mfpf_grad_corr2d, mfpf_hog_box_finder, mfpf_region_pdf, mfpf_norm_corr2d, mfpf_norm_corr1d, mfpf_profile_pdf, mfpf_edge_finder, and mfpf_max_finder.

double mfpf_point_finder::search_one_pose_with_opt	(	const vimt_image_2d_of< float > &	image,
		const vgl_point_2d< double > &	p0,
		const vgl_vector_2d< double > &	u,
		vgl_point_2d< double > &	new_p
	)		`[virtual]`

Search given image around p, using u to define scale and angle.

Evaluates responses on a grid, finds the best point on the grid, then optimises its position by fitting a parabola.

On exit, new_p defines position of the best nearby match. Returns a quality of fit measure at that point (the smaller the better).

Definition at line 193 of file mfpf_point_finder.cxx.

double mfpf_point_finder::search_with_opt	(	const vimt_image_2d_of< float > &	image,
		const vgl_point_2d< double > &	p,
		const vgl_vector_2d< double > &	u,
		vgl_point_2d< double > &	new_p,
		vgl_vector_2d< double > &	new_u
	)		`[virtual]`

Search given image around p, using u to define scale and orientation.

On exit, new_p and new_u define position, scale and orientation of the best nearby match. Returns a quality of fit measure at that point (the smaller the better). Parabolic fit used to estimate optimal position.

Default implementation calls search_one_pose(...) at multiple angles and scales. Result will be at a grid position and one of the given angle/scales. True optima can then be found by further optimisation of the point.

On exit, new_p and new_u define position, scale and orientation of the best nearby match. Returns a quality of fit measure at that point (the smaller the better).

Definition at line 283 of file mfpf_point_finder.cxx.