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Public Types | Public Member Functions | Static Public Member Functions | Protected Member Functions | Protected Attributes
vtkLinkEdgels Class Reference

links edgels together to form digital curves. More...

#include <vtkLinkEdgels.h>

Inheritance diagram for vtkLinkEdgels:
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Collaboration diagram for vtkLinkEdgels:
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List of all members.

Public Types

typedef vtkPolyDataAlgorithm Superclass
- Public Types inherited from vtkPolyDataAlgorithm
- Public Types inherited from vtkAlgorithm
- Public Types inherited from vtkObject

Public Member Functions

virtual const char * GetClassName ()
virtual int IsA (const char *type)
void PrintSelf (ostream &os, vtkIndent indent)
virtual void SetLinkThreshold (double)
virtual double GetLinkThreshold ()
virtual void SetPhiThreshold (double)
virtual double GetPhiThreshold ()
virtual void SetGradientThreshold (double)
virtual double GetGradientThreshold ()
- Public Member Functions inherited from vtkPolyDataAlgorithm
vtkDataObjectGetInput ()
vtkDataObjectGetInput (int port)
vtkPolyDataGetPolyDataInput (int port)
vtkPolyDataGetOutput ()
vtkPolyDataGetOutput (int)
virtual void SetOutput (vtkDataObject *d)
virtual int ProcessRequest (vtkInformation *, vtkInformationVector **, vtkInformationVector *)
void SetInput (vtkDataObject *)
void SetInput (int, vtkDataObject *)
void AddInput (vtkDataObject *)
void AddInput (int, vtkDataObject *)
- Public Member Functions inherited from vtkAlgorithm
int HasExecutive ()
vtkExecutiveGetExecutive ()
virtual void SetExecutive (vtkExecutive *executive)
virtual int ModifyRequest (vtkInformation *request, int when)
vtkInformationGetInputPortInformation (int port)
vtkInformationGetOutputPortInformation (int port)
int GetNumberOfInputPorts ()
int GetNumberOfOutputPorts ()
void UpdateProgress (double amount)
vtkInformationGetInputArrayInformation (int idx)
void RemoveAllInputs ()
vtkDataObjectGetOutputDataObject (int port)
virtual void RemoveInputConnection (int port, vtkAlgorithmOutput *input)
int GetNumberOfInputConnections (int port)
int GetTotalNumberOfInputConnections ()
vtkAlgorithmOutputGetInputConnection (int port, int index)
virtual void Update ()
virtual void UpdateInformation ()
virtual void UpdateWholeExtent ()
void ConvertTotalInputToPortConnection (int ind, int &port, int &conn)
virtual double ComputePriority ()
int ProcessRequest (vtkInformation *request, vtkCollection *inInfo, vtkInformationVector *outInfo)
virtual int ComputePipelineMTime (vtkInformation *request, vtkInformationVector **inInfoVec, vtkInformationVector *outInfoVec, int requestFromOutputPort, unsigned long *mtime)
virtual vtkInformationGetInformation ()
virtual void SetInformation (vtkInformation *)
virtual void Register (vtkObjectBase *o)
virtual void UnRegister (vtkObjectBase *o)
virtual void SetAbortExecute (int)
virtual int GetAbortExecute ()
virtual void AbortExecuteOn ()
virtual void AbortExecuteOff ()
virtual void SetProgress (double)
virtual double GetProgress ()
void SetProgressText (const char *ptext)
virtual char * GetProgressText ()
virtual unsigned long GetErrorCode ()
virtual void SetInputArrayToProcess (int idx, int port, int connection, int fieldAssociation, const char *name)
virtual void SetInputArrayToProcess (int idx, int port, int connection, int fieldAssociation, int fieldAttributeType)
virtual void SetInputArrayToProcess (int idx, vtkInformation *info)
virtual void SetInputArrayToProcess (int idx, int port, int connection, const char *fieldAssociation, const char *attributeTypeorName)
vtkDataObjectGetInputDataObject (int port, int connection)
virtual void SetInputConnection (int port, vtkAlgorithmOutput *input)
virtual void SetInputConnection (vtkAlgorithmOutput *input)
virtual void AddInputConnection (int port, vtkAlgorithmOutput *input)
virtual void AddInputConnection (vtkAlgorithmOutput *input)
vtkAlgorithmOutputGetOutputPort (int index)
vtkAlgorithmOutputGetOutputPort ()
virtual void SetReleaseDataFlag (int)
virtual int GetReleaseDataFlag ()
void ReleaseDataFlagOn ()
void ReleaseDataFlagOff ()
int UpdateExtentIsEmpty (vtkDataObject *output)
int UpdateExtentIsEmpty (vtkInformation *pinfo, int extentType)
- Public Member Functions inherited from vtkObject
virtual void DebugOn ()
virtual void DebugOff ()
unsigned char GetDebug ()
void SetDebug (unsigned char debugFlag)
virtual void Modified ()
virtual unsigned long GetMTime ()
unsigned long AddObserver (unsigned long event, vtkCommand *, float priority=0.0f)
unsigned long AddObserver (const char *event, vtkCommand *, float priority=0.0f)
vtkCommandGetCommand (unsigned long tag)
void RemoveObserver (vtkCommand *)
void RemoveObservers (unsigned long event, vtkCommand *)
void RemoveObservers (const char *event, vtkCommand *)
int HasObserver (unsigned long event, vtkCommand *)
int HasObserver (const char *event, vtkCommand *)
void RemoveObserver (unsigned long tag)
void RemoveObservers (unsigned long event)
void RemoveObservers (const char *event)
void RemoveAllObservers ()
int HasObserver (unsigned long event)
int HasObserver (const char *event)
template<class U , class T >
unsigned long AddObserver (unsigned long event, U observer, void(T::*callback)(), float priority=0.0f)
template<class U , class T >
unsigned long AddObserver (unsigned long event, U observer, void(T::*callback)(vtkObject *, unsigned long, void *), float priority=0.0f)
int InvokeEvent (unsigned long event, void *callData)
int InvokeEvent (const char *event, void *callData)
int InvokeEvent (unsigned long event)
int InvokeEvent (const char *event)
- Public Member Functions inherited from vtkObjectBase
const char * GetClassName () const
virtual void Delete ()
virtual void FastDelete ()
void Print (ostream &os)
void SetReferenceCount (int)
void PrintRevisions (ostream &os)
virtual void PrintHeader (ostream &os, vtkIndent indent)
virtual void PrintTrailer (ostream &os, vtkIndent indent)
int GetReferenceCount ()

Static Public Member Functions

static int IsTypeOf (const char *type)
static vtkLinkEdgelsSafeDownCast (vtkObject *o)
static vtkLinkEdgelsNew ()

Protected Member Functions

 vtkLinkEdgels ()
 ~vtkLinkEdgels ()
virtual int RequestData (vtkInformation *, vtkInformationVector **, vtkInformationVector *)
virtual int FillInputPortInformation (int port, vtkInformation *info)
void LinkEdgels (int xdim, int ydim, double *image, vtkDataArray *inVectors, vtkCellArray *newLines, vtkPoints *newPts, vtkDoubleArray *outScalars, vtkDoubleArray *outVectors, int z)
- Protected Member Functions inherited from vtkPolyDataAlgorithm
 vtkPolyDataAlgorithm ()
 ~vtkPolyDataAlgorithm ()
virtual int RequestInformation (vtkInformation *request, vtkInformationVector **inputVector, vtkInformationVector *outputVector)
virtual int FillOutputPortInformation (int port, vtkInformation *info)
virtual int RequestUpdateExtent (vtkInformation *, vtkInformationVector **, vtkInformationVector *)
virtual void ExecuteData (vtkDataObject *output)
virtual void Execute ()
- Protected Member Functions inherited from vtkAlgorithm
 vtkAlgorithm ()
 ~vtkAlgorithm ()
virtual void SetNumberOfInputPorts (int n)
virtual void SetNumberOfOutputPorts (int n)
int InputPortIndexInRange (int index, const char *action)
int OutputPortIndexInRange (int index, const char *action)
int GetInputArrayAssociation (int idx, vtkInformationVector **inputVector)
virtual vtkExecutiveCreateDefaultExecutive ()
virtual void ReportReferences (vtkGarbageCollector *)
virtual void SetNumberOfInputConnections (int port, int n)
int GetInputArrayAssociation (int idx, int connection, vtkInformationVector **inputVector)
int GetInputArrayAssociation (int idx, vtkDataObject *input)
vtkDataArrayGetInputArrayToProcess (int idx, vtkInformationVector **inputVector)
vtkDataArrayGetInputArrayToProcess (int idx, vtkInformationVector **inputVector, int &association)
vtkDataArrayGetInputArrayToProcess (int idx, int connection, vtkInformationVector **inputVector)
vtkDataArrayGetInputArrayToProcess (int idx, int connection, vtkInformationVector **inputVector, int &association)
vtkDataArrayGetInputArrayToProcess (int idx, vtkDataObject *input)
vtkDataArrayGetInputArrayToProcess (int idx, vtkDataObject *input, int &association)
vtkAbstractArrayGetInputAbstractArrayToProcess (int idx, vtkInformationVector **inputVector)
vtkAbstractArrayGetInputAbstractArrayToProcess (int idx, vtkInformationVector **inputVector, int &association)
vtkAbstractArrayGetInputAbstractArrayToProcess (int idx, int connection, vtkInformationVector **inputVector)
vtkAbstractArrayGetInputAbstractArrayToProcess (int idx, int connection, vtkInformationVector **inputVector, int &association)
vtkAbstractArrayGetInputAbstractArrayToProcess (int idx, vtkDataObject *input)
vtkAbstractArrayGetInputAbstractArrayToProcess (int idx, vtkDataObject *input, int &association)
vtkInformationGetInputArrayFieldInformation (int idx, vtkInformationVector **inputVector)
virtual void SetNthInputConnection (int port, int index, vtkAlgorithmOutput *input)
virtual void SetErrorCode (unsigned long)
- Protected Member Functions inherited from vtkObject
 vtkObject ()
virtual ~vtkObject ()
virtual void RegisterInternal (vtkObjectBase *, int check)
virtual void UnRegisterInternal (vtkObjectBase *, int check)
void InternalGrabFocus (vtkCommand *mouseEvents, vtkCommand *keypressEvents=NULL)
void InternalReleaseFocus ()
- Protected Member Functions inherited from vtkObjectBase
 vtkObjectBase ()
virtual ~vtkObjectBase ()
virtual void CollectRevisions (ostream &os)
 vtkObjectBase (const vtkObjectBase &)
void operator= (const vtkObjectBase &)

Protected Attributes

double GradientThreshold
double PhiThreshold
double LinkThreshold

Detailed Description

links edgels together to form digital curves.

vtkLinkEdgels links edgels into digital curves which are then stored as polylines. The algorithm works one pixel at a time only looking at its immediate neighbors. There is a GradientThreshold that can be set that eliminates any pixels with a smaller gradient value. This can be used as the lower threshold of a two value edgel thresholding.

For the remaining edgels, links are first tried for the four connected neighbors. A successful neighbor will satisfy three tests. First both edgels must be above the gradient threshold. Second, the difference between the orientation between the two edgels (Alpha) and each edgels orientation (Phi) must be less than LinkThreshold. Third, the difference between the two edgels Phi values must be less than PhiThreshold. The most successful link is selected. The measure is simply the sum of the three angle differences (actually stored as the sum of the cosines). If none of the four connect neighbors succeeds, then the eight connect neighbors are examined using the same method.

This filter requires gradient information so you will need to use a vtkImageGradient at some point prior to this filter. Typically a vtkNonMaximumSuppression filter is also used. vtkThresholdEdgels can be used to complete the two value edgel thresholding as used in a Canny edge detector. The vtkSubpixelPositionEdgels filter can also be used after this filter to adjust the edgel locations.

See also:
vtkImageData vtkImageGradient vtkImageNonMaximumSuppression
Tests:
vtkLinkEdgels (Tests)

Definition at line 60 of file vtkLinkEdgels.h.


Member Typedef Documentation

Reimplemented from vtkPolyDataAlgorithm.

Definition at line 63 of file vtkLinkEdgels.h.


Constructor & Destructor Documentation

vtkLinkEdgels::vtkLinkEdgels ( )
protected
vtkLinkEdgels::~vtkLinkEdgels ( )
inlineprotected

Definition at line 91 of file vtkLinkEdgels.h.


Member Function Documentation

virtual const char* vtkLinkEdgels::GetClassName ( )
virtual

Reimplemented from vtkPolyDataAlgorithm.

static int vtkLinkEdgels::IsTypeOf ( const char *  name)
static

Return 1 if this class type is the same type of (or a subclass of) the named class. Returns 0 otherwise. This method works in combination with vtkTypeMacro found in vtkSetGet.h.

Reimplemented from vtkPolyDataAlgorithm.

virtual int vtkLinkEdgels::IsA ( const char *  name)
virtual

Return 1 if this class is the same type of (or a subclass of) the named class. Returns 0 otherwise. This method works in combination with vtkTypeMacro found in vtkSetGet.h.

Reimplemented from vtkPolyDataAlgorithm.

static vtkLinkEdgels* vtkLinkEdgels::SafeDownCast ( vtkObject o)
static

Reimplemented from vtkPolyDataAlgorithm.

void vtkLinkEdgels::PrintSelf ( ostream &  os,
vtkIndent  indent 
)
virtual

Methods invoked by print to print information about the object including superclasses. Typically not called by the user (use Print() instead) but used in the hierarchical print process to combine the output of several classes.

Reimplemented from vtkPolyDataAlgorithm.

static vtkLinkEdgels* vtkLinkEdgels::New ( )
static

Construct instance of vtkLinkEdgels with GradientThreshold set to 0.1, PhiThreshold set to 90 degrees and LinkThreshold set to 90 degrees.

Reimplemented from vtkPolyDataAlgorithm.

virtual void vtkLinkEdgels::SetLinkThreshold ( double  )
virtual

Set/Get the threshold for Phi vs. Alpha link thresholding.

virtual double vtkLinkEdgels::GetLinkThreshold ( )
virtual

Set/Get the threshold for Phi vs. Alpha link thresholding.

virtual void vtkLinkEdgels::SetPhiThreshold ( double  )
virtual

Set/get the threshold for Phi vs. Phi link thresholding.

virtual double vtkLinkEdgels::GetPhiThreshold ( )
virtual

Set/get the threshold for Phi vs. Phi link thresholding.

virtual void vtkLinkEdgels::SetGradientThreshold ( double  )
virtual

Set/Get the threshold for image gradient thresholding.

virtual double vtkLinkEdgels::GetGradientThreshold ( )
virtual

Set/Get the threshold for image gradient thresholding.

virtual int vtkLinkEdgels::RequestData ( vtkInformation request,
vtkInformationVector **  inputVector,
vtkInformationVector outputVector 
)
protectedvirtual

This is called by the superclass. This is the method you should override.

Reimplemented from vtkPolyDataAlgorithm.

virtual int vtkLinkEdgels::FillInputPortInformation ( int  port,
vtkInformation info 
)
protectedvirtual

Fill the input port information objects for this algorithm. This is invoked by the first call to GetInputPortInformation for each port so subclasses can specify what they can handle.

Reimplemented from vtkPolyDataAlgorithm.

void vtkLinkEdgels::LinkEdgels ( int  xdim,
int  ydim,
double *  image,
vtkDataArray inVectors,
vtkCellArray newLines,
vtkPoints newPts,
vtkDoubleArray outScalars,
vtkDoubleArray outVectors,
int  z 
)
protected

Member Data Documentation

double vtkLinkEdgels::GradientThreshold
protected

Definition at line 100 of file vtkLinkEdgels.h.

double vtkLinkEdgels::PhiThreshold
protected

Definition at line 101 of file vtkLinkEdgels.h.

double vtkLinkEdgels::LinkThreshold
protected

Definition at line 102 of file vtkLinkEdgels.h.


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