SHOGUN  4.1.0
 All Classes Namespaces Files Functions Variables Typedefs Enumerations Enumerator Friends Macros Modules Pages
List of all members | Public Member Functions | Public Attributes | Protected Member Functions | Protected Attributes
CGraphCut Class Reference

Detailed Description

Graph cuts inference for fatcor graph using V. Kolmogorov's max-flow/min-cut algorithm

Please refer to the paper for more details:

"An Experimental Comparison of Min-Cut/Max-Flow Algorithms for Energy Minimization in Vision." Yuri Boykov and Vladimir Kolmogorov. In IEEE Transactions on Pattern Analysis and Machine Intelligence (PAMI), 2004.

Currently, only binary lablel is supported, factor order <= 3

Definition at line 106 of file GraphCut.h.

Inheritance diagram for CGraphCut:
Inheritance graph
[legend]

Public Member Functions

 CGraphCut ()
 
 CGraphCut (CFactorGraph *fg)
 
 CGraphCut (int32_t num_nodes, int32_t num_edges)
 
virtual ~CGraphCut ()
 
virtual const char * get_name () const
 
virtual float64_t inference (SGVector< int32_t > assignment)
 
float64_t get_flow ()
 
void build_st_graph (int32_t num_nodes, int32_t num_edges)
 
void add_edge (int32_t i, int32_t j, float64_t capacity, float64_t reverse_capacity)
 
void add_tweights (int32_t i, float64_t cap_source, float64_t cap_sink)
 
void init_maxflow ()
 
float64_t compute_maxflow ()
 
ETerminalType get_assignment (int32_t i, ETerminalType default_terminal=SOURCE)
 
void print_graph ()
 
void print_assignment ()
 
virtual CSGObject * shallow_copy () const
 
virtual CSGObject * deep_copy () const
 
virtual bool is_generic (EPrimitiveType *generic) const
 
template<class T >
void set_generic ()
 
template<>
void set_generic ()
 
template<>
void set_generic ()
 
template<>
void set_generic ()
 
template<>
void set_generic ()
 
template<>
void set_generic ()
 
template<>
void set_generic ()
 
template<>
void set_generic ()
 
template<>
void set_generic ()
 
template<>
void set_generic ()
 
template<>
void set_generic ()
 
template<>
void set_generic ()
 
template<>
void set_generic ()
 
template<>
void set_generic ()
 
template<>
void set_generic ()
 
template<>
void set_generic ()
 
void unset_generic ()
 
virtual void print_serializable (const char *prefix="")
 
virtual bool save_serializable (CSerializableFile *file, const char *prefix="")
 
virtual bool load_serializable (CSerializableFile *file, const char *prefix="")
 
void set_global_io (SGIO *io)
 
SGIO * get_global_io ()
 
void set_global_parallel (Parallel *parallel)
 
Parallel * get_global_parallel ()
 
void set_global_version (Version *version)
 
Version * get_global_version ()
 
SGStringList< char > get_modelsel_names ()
 
void print_modsel_params ()
 
char * get_modsel_param_descr (const char *param_name)
 
index_t get_modsel_param_index (const char *param_name)
 
void build_gradient_parameter_dictionary (CMap< TParameter *, CSGObject * > *dict)
 
virtual void update_parameter_hash ()
 
virtual bool parameter_hash_changed ()
 
virtual bool equals (CSGObject *other, float64_t accuracy=0.0, bool tolerant=false)
 
virtual CSGObject * clone ()
 

Public Attributes

SGIO * io
 
Parallel * parallel
 
Version * version
 
Parameter * m_parameters
 
Parameter * m_model_selection_parameters
 
Parameter * m_gradient_parameters
 
uint32_t m_hash
 

Protected Member Functions

virtual void load_serializable_pre () throw (ShogunException)
 
virtual void load_serializable_post () throw (ShogunException)
 
virtual void save_serializable_pre () throw (ShogunException)
 
virtual void save_serializable_post () throw (ShogunException)
 

Protected Attributes

float64_t m_map_energy
 
CFactorGraph * m_fg
 

Constructor & Destructor Documentation

CGraphCut ( )

Constructor

Definition at line 16 of file GraphCut.cpp.

CGraphCut ( CFactorGraph *  fg)

Constructor

Parameters
fgfactor graph

Definition at line 24 of file GraphCut.cpp.

CGraphCut ( int32_t  num_nodes,
int32_t  num_edges 
)

Constructor This constructor is used for general s-t graph, the next steps to compute the max flow are:

  1. use add_tweight and add_edges to add nodes and edges to the s-t graph
  2. init_maxflow()
  3. compute_maxflow()
Parameters
num_nodesnumber of nodes in the s-t graph (SOURCE and SINK nodes are not included)
num_edgesnumber of edges in the s-t graph (the edges connecting to the SOURCE and SINK are not included)

Definition at line 32 of file GraphCut.cpp.

~CGraphCut ( )
virtual

Destructor

Definition at line 42 of file GraphCut.cpp.

Member Function Documentation

void add_edge ( int32_t  i,
int32_t  j,
float64_t  capacity,
float64_t  reverse_capacity 
)

Adds a bidirectional edge between 'i' and 'j' with the weights 'cap' and 'rev_cap'.

Parameters
inode id i
jnode id j
capacityedge capacity
reverse_capacityreverse edge capacity

Definition at line 451 of file GraphCut.cpp.

void add_tweights ( int32_t  i,
float64_t  cap_source,
float64_t  cap_sink 
)

Adds new edges 'SOURCE->i' and 'i->SINK' with corresponding weights. Can be called multiple times for each node. Weights can be negative. NOTE: the number of such edges is not counted in edge_num_max. No internal memory is allocated by this call.

Parameters
inode id i
cap_sourceSOURCE->i capacity
cap_sinki->SINK capacity

Definition at line 431 of file GraphCut.cpp.

void build_gradient_parameter_dictionary ( CMap< TParameter *, CSGObject * > *  dict)
inherited

Builds a dictionary of all parameters in SGObject as well of those of SGObjects that are parameters of this object. Dictionary maps parameters to the objects that own them.

Parameters
dictdictionary of parameters to be built.

Definition at line 597 of file SGObject.cpp.

void build_st_graph ( int32_t  num_nodes,
int32_t  num_edges 
)

Build s-t graph

Parameters
num_nodesnumber of nodes in the s-t graph (SOURCE and SINK nodes are not included)
num_edgesnumber of edges in the s-t graph (the edges connecting to the SOURCE and SINK are not included)

Definition at line 122 of file GraphCut.cpp.

CSGObject * clone ( )
virtualinherited

Creates a clone of the current object. This is done via recursively traversing all parameters, which corresponds to a deep copy. Calling equals on the cloned object always returns true although none of the memory of both objects overlaps.

Returns
an identical copy of the given object, which is disjoint in memory. NULL if the clone fails. Note that the returned object is SG_REF'ed

Definition at line 714 of file SGObject.cpp.

float64_t compute_maxflow ( )

Compute the maxflow

The algorithm builds up two search trees, a source-tree and a sink-tree. In the beginning of the algorithm only the source and the sink nodes and all other nodes are free nodes. The algorithm consists of three phases:

grow-phase: In this phase active nodes aquire new children from a set of free nodes. The grow phase terminates if there are no more active nodes left or a node discovers a node from the other search tree through an unsaturated edge. In this case a path from source to sink is found.

augmentation-pahse: the input for this stage is a path P from s to t found at the growth stage. Some nodes may become "orphans" because their parents are no longer valid as they are on the augmented path and saturated.

adoption-phase: the adoption stage tries to find a new valid parent for each orphan. A parent should be in the same set (SOURCE or SINK), as the orphan and connected through a non-saturated edge. The stage terminates when no orphans are left and the search tree of SOURCE and SINK are restored.

After the adoption stage is completed, the algorithm returns to the growth stage. The algorithm terminates when the search tree cannot grow (no active nodes) and the trees are seperated by saturated edges. This implies that a maximum flow is achieved.

Returns
the total flow after computing max flow

Definition at line 540 of file GraphCut.cpp.

CSGObject * deep_copy ( ) const
virtualinherited

A deep copy. All the instance variables will also be copied.

Definition at line 198 of file SGObject.cpp.

bool equals ( CSGObject *  other,
float64_t  accuracy = 0.0,
bool  tolerant = false 
)
virtualinherited

Recursively compares the current SGObject to another one. Compares all registered numerical parameters, recursion upon complex (SGObject) parameters. Does not compare pointers!

May be overwritten but please do with care! Should not be necessary in most cases.

Parameters
otherobject to compare with
accuracyaccuracy to use for comparison (optional)
tolerantallows linient check on float equality (within accuracy)
Returns
true if all parameters were equal, false if not

Definition at line 618 of file SGObject.cpp.

ETerminalType get_assignment ( int32_t  i,
ETerminalType  default_terminal = SOURCE 
)

After the maxflow is computed, this function returns to which terminal the node 'i' belongs (ETerminalType::SOURCE or ETerminalType::SINK).

Occasionally there may be several minimum cuts. If a node can be assigned to both the source and the sink, then default_terminal is returned.

Parameters
inode id
default_terminaldefault terminal
Returns
terminal that the node belongs to

Definition at line 944 of file GraphCut.cpp.

float64_t get_flow ( )
Returns
the total flow in the s-t graph

Definition at line 146 of file GraphCut.h.

SGIO * get_global_io ( )
inherited

get the io object

Returns
io object

Definition at line 235 of file SGObject.cpp.

Parallel * get_global_parallel ( )
inherited

get the parallel object

Returns
parallel object

Definition at line 277 of file SGObject.cpp.

Version * get_global_version ( )
inherited

get the version object

Returns
version object

Definition at line 290 of file SGObject.cpp.

SGStringList< char > get_modelsel_names ( )
inherited
Returns
vector of names of all parameters which are registered for model selection

Definition at line 498 of file SGObject.cpp.

char * get_modsel_param_descr ( const char *  param_name)
inherited

Returns description of a given parameter string, if it exists. SG_ERROR otherwise

Parameters
param_namename of the parameter
Returns
description of the parameter

Definition at line 522 of file SGObject.cpp.

index_t get_modsel_param_index ( const char *  param_name)
inherited

Returns index of model selection parameter with provided index

Parameters
param_namename of model selection parameter
Returns
index of model selection parameter with provided name, -1 if there is no such

Definition at line 535 of file SGObject.cpp.

virtual const char* get_name ( ) const
virtual
Returns
class name

Reimplemented from CMAPInferImpl.

Definition at line 133 of file GraphCut.h.

float64_t inference ( SGVector< int32_t >  assignment)
virtual

Inference

Parameters
assignmentthe assignment
Returns
the total energy after doing inference

Implements CMAPInferImpl.

Definition at line 193 of file GraphCut.cpp.

void init_maxflow ( )

Initialize max flow, call this function after adding nodes and edges

Definition at line 151 of file GraphCut.cpp.

bool is_generic ( EPrimitiveType *  generic) const
virtualinherited

If the SGSerializable is a class template then TRUE will be returned and GENERIC is set to the type of the generic.

Parameters
genericset to the type of the generic if returning TRUE
Returns
TRUE if a class template.

Definition at line 296 of file SGObject.cpp.

bool load_serializable ( CSerializableFile *  file,
const char *  prefix = "" 
)
virtualinherited

Load this object from file. If it will fail (returning FALSE) then this object will contain inconsistent data and should not be used!

Parameters
filewhere to load from
prefixprefix for members
Returns
TRUE if done, otherwise FALSE

Definition at line 369 of file SGObject.cpp.

void load_serializable_post ( )
throw (ShogunException
)
protectedvirtualinherited

Can (optionally) be overridden to post-initialize some member variables which are not PARAMETER::ADD'ed. Make sure that at first the overridden method BASE_CLASS::LOAD_SERIALIZABLE_POST is called.

Exceptions
ShogunExceptionwill be thrown if an error occurs.

Reimplemented in CKernel, CWeightedDegreePositionStringKernel, CList, CAlphabet, CLinearHMM, CGaussianKernel, CInverseMultiQuadricKernel, CCircularKernel, and CExponentialKernel.

Definition at line 426 of file SGObject.cpp.

void load_serializable_pre ( )
throw (ShogunException
)
protectedvirtualinherited

Can (optionally) be overridden to pre-initialize some member variables which are not PARAMETER::ADD'ed. Make sure that at first the overridden method BASE_CLASS::LOAD_SERIALIZABLE_PRE is called.

Exceptions
ShogunExceptionwill be thrown if an error occurs.

Reimplemented in CDynamicArray< T >, CDynamicArray< float64_t >, CDynamicArray< float32_t >, CDynamicArray< int32_t >, CDynamicArray< char >, CDynamicArray< bool >, and CDynamicObjectArray.

Definition at line 421 of file SGObject.cpp.

bool parameter_hash_changed ( )
virtualinherited
Returns
whether parameter combination has changed since last update

Definition at line 262 of file SGObject.cpp.

void print_assignment ( )

Print assignment

Definition at line 984 of file GraphCut.cpp.

void print_graph ( )

Print the s-t graph

Definition at line 956 of file GraphCut.cpp.

void print_modsel_params ( )
inherited

prints all parameter registered for model selection and their type

Definition at line 474 of file SGObject.cpp.

void print_serializable ( const char *  prefix = "")
virtualinherited

prints registered parameters out

Parameters
prefixprefix for members

Definition at line 308 of file SGObject.cpp.

bool save_serializable ( CSerializableFile *  file,
const char *  prefix = "" 
)
virtualinherited

Save this object to file.

Parameters
filewhere to save the object; will be closed during returning if PREFIX is an empty string.
prefixprefix for members
Returns
TRUE if done, otherwise FALSE

Definition at line 314 of file SGObject.cpp.

void save_serializable_post ( )
throw (ShogunException
)
protectedvirtualinherited

Can (optionally) be overridden to post-initialize some member variables which are not PARAMETER::ADD'ed. Make sure that at first the overridden method BASE_CLASS::SAVE_SERIALIZABLE_POST is called.

Exceptions
ShogunExceptionwill be thrown if an error occurs.

Reimplemented in CKernel.

Definition at line 436 of file SGObject.cpp.

void save_serializable_pre ( )
throw (ShogunException
)
protectedvirtualinherited

Can (optionally) be overridden to pre-initialize some member variables which are not PARAMETER::ADD'ed. Make sure that at first the overridden method BASE_CLASS::SAVE_SERIALIZABLE_PRE is called.

Exceptions
ShogunExceptionwill be thrown if an error occurs.

Reimplemented in CKernel, CDynamicArray< T >, CDynamicArray< float64_t >, CDynamicArray< float32_t >, CDynamicArray< int32_t >, CDynamicArray< char >, CDynamicArray< bool >, and CDynamicObjectArray.

Definition at line 431 of file SGObject.cpp.

void set_generic ( )
inherited

Definition at line 41 of file SGObject.cpp.

void set_generic ( )
inherited

Definition at line 46 of file SGObject.cpp.

void set_generic ( )
inherited

Definition at line 51 of file SGObject.cpp.

void set_generic ( )
inherited

Definition at line 56 of file SGObject.cpp.

void set_generic ( )
inherited

Definition at line 61 of file SGObject.cpp.

void set_generic ( )
inherited

Definition at line 66 of file SGObject.cpp.

void set_generic ( )
inherited

Definition at line 71 of file SGObject.cpp.

void set_generic ( )
inherited

Definition at line 76 of file SGObject.cpp.

void set_generic ( )
inherited

Definition at line 81 of file SGObject.cpp.

void set_generic ( )
inherited

Definition at line 86 of file SGObject.cpp.

void set_generic ( )
inherited

Definition at line 91 of file SGObject.cpp.

void set_generic ( )
inherited

Definition at line 96 of file SGObject.cpp.

void set_generic ( )
inherited

Definition at line 101 of file SGObject.cpp.

void set_generic ( )
inherited

Definition at line 106 of file SGObject.cpp.

void set_generic ( )
inherited

Definition at line 111 of file SGObject.cpp.

void set_generic ( )
inherited

set generic type to T

void set_global_io ( SGIO *  io)
inherited

set the io object

Parameters
ioio object to use

Definition at line 228 of file SGObject.cpp.

void set_global_parallel ( Parallel *  parallel)
inherited

set the parallel object

Parameters
parallelparallel object to use

Definition at line 241 of file SGObject.cpp.

void set_global_version ( Version *  version)
inherited

set the version object

Parameters
versionversion object to use

Definition at line 283 of file SGObject.cpp.

CSGObject * shallow_copy ( ) const
virtualinherited

A shallow copy. All the SGObject instance variables will be simply assigned and SG_REF-ed.

Reimplemented in CGaussianKernel.

Definition at line 192 of file SGObject.cpp.

void unset_generic ( )
inherited

unset generic type

this has to be called in classes specializing a template class

Definition at line 303 of file SGObject.cpp.

void update_parameter_hash ( )
virtualinherited

Updates the hash of current parameter combination

Definition at line 248 of file SGObject.cpp.

Member Data Documentation

SGIO* io
inherited

io

Definition at line 369 of file SGObject.h.

CFactorGraph* m_fg
protectedinherited

pointer of factor graph

Definition at line 128 of file MAPInference.h.

Parameter* m_gradient_parameters
inherited

parameters wrt which we can compute gradients

Definition at line 384 of file SGObject.h.

uint32_t m_hash
inherited

Hash of parameter values

Definition at line 387 of file SGObject.h.

float64_t m_map_energy
protected

the total energy of the factor graph

Definition at line 307 of file GraphCut.h.

Parameter* m_model_selection_parameters
inherited

model selection parameters

Definition at line 381 of file SGObject.h.

Parameter* m_parameters
inherited

parameters

Definition at line 378 of file SGObject.h.

Parallel* parallel
inherited

parallel

Definition at line 372 of file SGObject.h.

Version* version
inherited

version

Definition at line 375 of file SGObject.h.

The documentation for this class was generated from the following files:
SHOGUN Machine Learning Toolbox - Documentation