Public Member Functions | Protected Member Functions | Protected Attributes | Private Member Functions | Private Attributes
mfpf_grad_corr2d Class Reference

Searches over a grid using normalised correlation. More...

#include <mfpf_grad_corr2d.h>

Inheritance diagram for mfpf_grad_corr2d:
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List of all members.

Public Member Functions

 mfpf_grad_corr2d ()
virtual ~mfpf_grad_corr2d ()
void set (const vil_image_view< double > &kx, const vil_image_view< double > &ky)
 Define filter kernel to search with.
void set (const vil_image_view< double > &kx, const vil_image_view< double > &ky, double ref_x, double ref_y)
 Define filter kernel to search with.
virtual bool set_model (const vcl_vector< double > &v)
 Define filter kernel to search with, expressed as a vector.
virtual unsigned model_dim ()
 Number of dimensions in the model.
void set_overlap_f (double)
 Relative size of region used for estimating overlap.
const vil_image_view< double > & kernel_x () const
 Filter x-gradient kernel to search with.
const vil_image_view< double > & kernel_y () const
 Filter y-gradient kernel to search with.
void get_kernel_vector (vcl_vector< double > &v) const
 Filter kernel to search with, expressed as a vector.
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 radius () const
 Radius of circle containing modelled region.
virtual double evaluate (const vimt_image_2d_of< float > &image, const vgl_point_2d< double > &p, const vgl_vector_2d< double > &u)
 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)
 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)
 Search given image around p, using u to define scale and angle.
bool is_inside (const mfpf_pose &pose, const vgl_point_2d< double > &p, double f=1.0) const
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
 Generate points in ref frame that represent boundary.
virtual void get_image_of_model (vimt_image_2d_of< vxl_byte > &image) const
 Return an image of the kernel.
short version_no () const
 Version number for I/O.
virtual vcl_string is_a () const
 Name of the class.
virtual mfpf_point_finderclone () const
 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.
bool operator== (const mfpf_grad_corr2d &nc) const
 Test equality.
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 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 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.
unsigned image_level (const mfpf_pose &pose, const vimt_image_pyramid &im_pyr) const
 Select best level for searching around pose.

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].

Private Member Functions

void set_defaults ()
 Define default values.
void diff_image (const vimt_image_2d_of< float > &image, const vgl_point_2d< double > &p, const vgl_vector_2d< double > &u, vil_image_view< double > &grad_x, vil_image_view< double > &grad_y, int search_ni=0, int search_nj=0)
 Compute gradient image around a patch.

Private Attributes

double ref_x_
 Kernel reference point (in kni_ x knj_ grid).
double ref_y_
 Kernel reference point (in kni_ x knj_ grid).
double overlap_f_
 Relative size of region used for estimating overlap.
vil_image_view< double > kernel_x_
 Filter x-gradient kernel to search with.
vil_image_view< double > kernel_y_
 Filter y-gradient kernel to search with.

Detailed Description

Searches over a grid using normalised correlation.

Definition at line 13 of file mfpf_grad_corr2d.h.


Constructor & Destructor Documentation

mfpf_grad_corr2d::mfpf_grad_corr2d ( )

Definition at line 25 of file mfpf_grad_corr2d.cxx.

mfpf_grad_corr2d::~mfpf_grad_corr2d ( ) [virtual]

Definition at line 47 of file mfpf_grad_corr2d.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, inherited]

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_grad_corr2d::b_read ( vsl_b_istream bfs) [virtual]

Load class from binary file stream.

Reimplemented from mfpf_point_finder.

Definition at line 553 of file mfpf_grad_corr2d.cxx.

void mfpf_grad_corr2d::b_write ( vsl_b_ostream bfs) const [virtual]

Save class to binary file stream.

Reimplemented from mfpf_point_finder.

Definition at line 533 of file mfpf_grad_corr2d.cxx.

bool mfpf_point_finder::base_equality ( const mfpf_point_finder pf) const [protected, inherited]

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

Definition at line 627 of file mfpf_point_finder.cxx.

mfpf_point_finder * mfpf_grad_corr2d::clone ( ) const [virtual]

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

Implements mfpf_point_finder.

Definition at line 517 of file mfpf_grad_corr2d.cxx.

void mfpf_grad_corr2d::diff_image ( const vimt_image_2d_of< float > &  image,
const vgl_point_2d< double > &  p,
const vgl_vector_2d< double > &  u,
vil_image_view< double > &  grad_x,
vil_image_view< double > &  grad_y,
int  search_ni = 0,
int  search_nj = 0 
) [private]

Compute gradient image around a patch.

Definition at line 215 of file mfpf_grad_corr2d.cxx.

double mfpf_grad_corr2d::evaluate ( const vimt_image_2d_of< float > &  image,
const vgl_point_2d< double > &  p,
const vgl_vector_2d< double > &  u 
) [virtual]

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

Returns -1*edge strength at p along direction u

Implements mfpf_point_finder.

Definition at line 323 of file mfpf_grad_corr2d.cxx.

void mfpf_grad_corr2d::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 
) [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.

Implements mfpf_point_finder.

Definition at line 345 of file mfpf_grad_corr2d.cxx.

void mfpf_grad_corr2d::get_image_of_model ( vimt_image_2d_of< vxl_byte > &  image) const [virtual]

Return an image of the kernel.

Reimplemented from mfpf_point_finder.

Definition at line 492 of file mfpf_grad_corr2d.cxx.

void mfpf_grad_corr2d::get_kernel_vector ( vcl_vector< double > &  v) const

Filter kernel to search with, expressed as a vector.

Definition at line 142 of file mfpf_grad_corr2d.cxx.

void mfpf_grad_corr2d::get_outline ( vcl_vector< vgl_point_2d< double > > &  pts) const [virtual]

Generate points in ref frame that represent boundary.

Points of a contour around the shape. Used for display purposes.

Implements mfpf_point_finder.

Definition at line 476 of file mfpf_grad_corr2d.cxx.

void mfpf_grad_corr2d::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 from mfpf_point_finder.

Definition at line 286 of file mfpf_grad_corr2d.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, inherited]

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, inherited]

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 [inherited]

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_grad_corr2d::is_a ( ) const [virtual]

Name of the class.

Reimplemented from mfpf_point_finder.

Definition at line 511 of file mfpf_grad_corr2d.cxx.

bool mfpf_grad_corr2d::is_inside ( const mfpf_pose pose,
const vgl_point_2d< double > &  p,
double  f = 1.0 
) const

Definition at line 446 of file mfpf_grad_corr2d.cxx.

const vil_image_view<double>& mfpf_grad_corr2d::kernel_x ( ) const [inline]

Filter x-gradient kernel to search with.

Definition at line 69 of file mfpf_grad_corr2d.h.

const vil_image_view<double>& mfpf_grad_corr2d::kernel_y ( ) const [inline]

Filter y-gradient kernel to search with.

Definition at line 72 of file mfpf_grad_corr2d.h.

unsigned mfpf_grad_corr2d::model_dim ( ) [virtual]

Number of dimensions in the model.

Reimplemented from mfpf_point_finder.

Definition at line 136 of file mfpf_grad_corr2d.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, inherited]

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, inherited]

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_grad_corr2d::operator== ( const mfpf_grad_corr2d nc) const

Test equality.

Definition at line 579 of file mfpf_grad_corr2d.cxx.

bool mfpf_grad_corr2d::overlap ( const mfpf_pose pose1,
const mfpf_pose pose2 
) const [virtual]

Return true if modelled regions at pose1 and pose2 overlap.

Checks if reference point of one is inside region of other

Reimplemented from mfpf_point_finder.

Definition at line 465 of file mfpf_grad_corr2d.cxx.

void mfpf_grad_corr2d::print_summary ( vcl_ostream &  os) const [virtual]

Print class to os.

Reimplemented from mfpf_point_finder.

Definition at line 526 of file mfpf_grad_corr2d.cxx.

double mfpf_grad_corr2d::radius ( ) const [virtual]

Radius of circle containing modelled region.

Implements mfpf_point_finder.

Definition at line 309 of file mfpf_grad_corr2d.cxx.

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, inherited]

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, inherited]

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, inherited]

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, inherited]

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

Definition at line 79 of file mfpf_point_finder.h.

double mfpf_grad_corr2d::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 
) [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).

Implements mfpf_point_finder.

Definition at line 400 of file mfpf_grad_corr2d.cxx.

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, inherited]

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, inherited]

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.

void mfpf_grad_corr2d::set ( const vil_image_view< double > &  kx,
const vil_image_view< double > &  ky 
)

Define filter kernel to search with.

Reference point set to the centre

Definition at line 104 of file mfpf_grad_corr2d.cxx.

void mfpf_grad_corr2d::set ( const vil_image_view< double > &  kx,
const vil_image_view< double > &  ky,
double  ref_x,
double  ref_y 
)

Define filter kernel to search with.

Definition at line 52 of file mfpf_grad_corr2d.cxx.

void mfpf_point_finder::set_angle_range ( unsigned  nA,
double  dA 
) [inherited]

Define angle search parameters.

Definition at line 151 of file mfpf_point_finder.cxx.

void mfpf_grad_corr2d::set_defaults ( ) [private]

Define default values.

Definition at line 31 of file mfpf_grad_corr2d.cxx.

bool mfpf_grad_corr2d::set_model ( const vcl_vector< double > &  v) [virtual]

Define filter kernel to search with, expressed as a vector.

Reimplemented from mfpf_point_finder.

Definition at line 111 of file mfpf_grad_corr2d.cxx.

void mfpf_grad_corr2d::set_overlap_f ( double  f)

Relative size of region used for estimating overlap.

If 0.5, then overlap requires pt inside central 50% of region.

Definition at line 160 of file mfpf_grad_corr2d.cxx.

void mfpf_point_finder::set_scale_range ( unsigned  ns,
double  ds 
) [inherited]

Define scale search parameters.

Definition at line 158 of file mfpf_point_finder.cxx.

void mfpf_point_finder::set_search_area ( unsigned  ni,
unsigned  nj 
) [virtual, inherited]

Define search region size.

During search, samples at points on grid [-ni,ni]x[-nj,nj], with axes defined by u.

Definition at line 144 of file mfpf_point_finder.cxx.

void mfpf_point_finder::set_step_size ( double  s) [virtual, inherited]

Size of step between sample points.

Definition at line 136 of file mfpf_point_finder.cxx.

double mfpf_point_finder::step_size ( ) const [inline, inherited]

Size of step between sample points.

Definition at line 62 of file mfpf_point_finder.h.

short mfpf_grad_corr2d::version_no ( ) const

Version number for I/O.

Reimplemented from mfpf_point_finder.

Definition at line 544 of file mfpf_grad_corr2d.cxx.


Member Data Documentation

double mfpf_point_finder::dA_ [protected, inherited]

Angle step size (ie try at A+idA, i in [-nA,+nA]).

Definition at line 40 of file mfpf_point_finder.h.

double mfpf_point_finder::ds_ [protected, inherited]

Scaling factor (ie try at ((ds)^i), i in [-ns,+ns].

Definition at line 46 of file mfpf_point_finder.h.

Filter x-gradient kernel to search with.

Definition at line 26 of file mfpf_grad_corr2d.h.

Filter y-gradient kernel to search with.

Definition at line 29 of file mfpf_grad_corr2d.h.

unsigned mfpf_point_finder::nA_ [protected, inherited]

Define N. angles (ie try at A+idA, i in [-nA,+nA]).

Definition at line 37 of file mfpf_point_finder.h.

unsigned mfpf_point_finder::ns_ [protected, inherited]

Number of scales to try at.

Definition at line 43 of file mfpf_point_finder.h.

double mfpf_grad_corr2d::overlap_f_ [private]

Relative size of region used for estimating overlap.

If 0.5, then overlap requires pt inside central 50% of region.

Definition at line 23 of file mfpf_grad_corr2d.h.

double mfpf_grad_corr2d::ref_x_ [private]

Kernel reference point (in kni_ x knj_ grid).

Definition at line 17 of file mfpf_grad_corr2d.h.

double mfpf_grad_corr2d::ref_y_ [private]

Kernel reference point (in kni_ x knj_ grid).

Definition at line 19 of file mfpf_grad_corr2d.h.

int mfpf_point_finder::search_ni_ [protected, inherited]

Number of points either side of centre to search.

Definition at line 31 of file mfpf_point_finder.h.

int mfpf_point_finder::search_nj_ [protected, inherited]

Number of points either side of centre to search.

Definition at line 34 of file mfpf_point_finder.h.

double mfpf_point_finder::step_size_ [protected, inherited]

Size of step between sample points.

Definition at line 28 of file mfpf_point_finder.h.


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