stir::SeparableConvolutionImageFilter< elemT > Class Template Reference

A class derived from DataProcessor for performing separable non-periodic convolutions. More...

#include "stir/SeparableConvolutionImageFilter.h"

Inheritance diagram for stir::SeparableConvolutionImageFilter< elemT >:

Public Member Functions
	SeparableConvolutionImageFilter ()
	Default constructor.
	SeparableConvolutionImageFilter (const VectorWithOffset< VectorWithOffset< elemT >> &filter_coefficients)
	Constructor taking filter coefficients explicitly. More...
template<>
const char *const	registered_name
VectorWithOffset< VectorWithOffset< elemT > >	get_filter_coefficients ()
	Overloaded get and set methods the filter coefficients for axis or set of filter coefficients.
void	set_filter_coefficients (const VectorWithOffset< VectorWithOffset< elemT >> &v)
VectorWithOffset< elemT >	get_filter_coefficients (const int axis)
void	set_filter_coefficients (const int axis, const VectorWithOffset< elemT > &v)
Public Member Functions inherited from stir::RegisteredParsingObject< SeparableConvolutionImageFilter< elemT >, DataProcessor< DiscretisedDensity< 3, elemT > >, DataProcessor< DiscretisedDensity< 3, elemT > > >
std::string	get_registered_name () const override
	Returns Derived::registered_name.
std::string	parameter_info () override
	Returns a string with all parameters and their values, in a form suitable for parsing again.
Public Member Functions inherited from stir::DataProcessor< DiscretisedDensity< 3, elemT > >
Succeeded	set_up (const DiscretisedDensity< 3, elemT > &data)
	Initialises any internal data (if necessary) using data as a template for sizes, sampling distances etc. More...
virtual void	reset ()
	Makes sure we will ignore any previous call to set-up() More...
Succeeded	apply (DiscretisedDensity< 3, elemT > &data)
	Calls set_up() (if not already done before) and process data in-place. More...
Succeeded	apply (DiscretisedDensity< 3, elemT > &out_data, const DiscretisedDensity< 3, elemT > &in_data)
	Calls set_up() (if not already done before) and process in_data, putting the result in out_data. More...
bool	parse (std::istream &f)
bool	parse (const char *const filename)
Public Member Functions inherited from stir::ParsingObject
	ParsingObject (const ParsingObject &)
ParsingObject &	operator= (const ParsingObject &)
void	ask_parameters ()
bool	parse (std::istream &f)
bool	parse (const char *const filename)
Public Member Functions inherited from stir::TimedObject
void	reset_timers ()
	reset all timers kept by this object
void	stop_timers () const
	stop all timers kept by this object More...
void	start_timers (bool do_reset=false) const
	start all timers kept by this object More...
double	get_CPU_timer_value () const
	get current value of the CPU timer (since first use or last reset)
double	get_wall_clock_timer_value () const
	get current value of the wall-clock timer (since first use or last reset)

Static Public Attributes
static const char *const	registered_name
	Name for parsing registry.

Additional Inherited Members
Static Public Member Functions inherited from stir::RegisteredParsingObject< SeparableConvolutionImageFilter< elemT >, DataProcessor< DiscretisedDensity< 3, elemT > >, DataProcessor< DiscretisedDensity< 3, elemT > > >
static DataProcessor< DiscretisedDensity< 3, elemT > > *	read_from_stream (std::istream *)
	Construct a new object (of type Derived) by parsing the istream. More...
Static Public Member Functions inherited from stir::RegisteredObject< Root >
static Root *	read_registered_object (std::istream *in, const std::string &registered_name)
	Construct a new object (of a type derived from Root, its actual type determined by the registered_name parameter) by parsing the istream. More...
static Root *	ask_type_and_parameters ()
	ask the user for the type, and then calls read_registered_object(0, type) More...
static void	list_registered_names (std::ostream &stream)
	List all possible registered names to the stream. More...
Protected Types inherited from stir::RegisteredObject< Root >
typedef Root *(*	RootFactory) (std::istream *)
	The type of a root factory is a function, taking an istream* as argument, and returning a Root*.
typedef FactoryRegistry< std::string, RootFactory, interfile_less >	RegistryType
	The type of the registry.
Protected Member Functions inherited from stir::DataProcessor< DiscretisedDensity< 3, elemT > >
virtual Succeeded	virtual_set_up (const DiscretisedDensity< 3, elemT > &)=0
	Will be called to build any internal parameters.
virtual void	virtual_apply (DiscretisedDensity< 3, elemT > &data, const DiscretisedDensity< 3, elemT > &in_data) const=0
	Performs actual operation (virtual_set_up is called before this function)
virtual void	virtual_apply (DiscretisedDensity< 3, elemT > &data) const=0
	Performs actual operation (in-place)
Protected Member Functions inherited from stir::ParsingObject
virtual void	set_key_values ()
	This will be called before parsing or parameter_info is called. More...
Static Protected Member Functions inherited from stir::RegisteredObject< Root >
static RegistryType &	registry ()
	Static function returning the registry. More...
Protected Attributes inherited from stir::ParsingObject
KeyParser	parser

Detailed Description

template<typename elemT>
class stir::SeparableConvolutionImageFilter< elemT >

A class derived from DataProcessor for performing separable non-periodic convolutions.

This filter applies a 1D convolution in all directions (z,y,x) with potentially a different filter kernel for every direction.

When parsing, the filter coefficients are read as a list of numbers for each direction. The following conventions is used:

1. A list of 0 length (which is the default) corresponds to no filtering.
2. When the list contains an even number of data, a 0 is appended (at the end).
3. After this, the central element of the list corresponds to the 0-th element in the kernel, see below.

Convolution is non-periodic. In each direction, the following is applied:

Note that for most kernels, the above convention means that the zero- index of the kernel corresponds to the peak in the kernel.

Elements of the input array that are outside its index range are considered to be 0.

Warning

There is NO check if the kernel coefficients add up to 1. This is because not all filters need this (e.g. edge enhancing filters).

Example input for a low-pass filter in x,y, no filtering in z

  Separable Convolution Parameters :=
  x-dir filter coefficients := {0.25, .5, .25}
  y-dir filter coefficients := {0.25, .5, .25}
  ;z-dir filter coefficients :=
  END Separable Convolution Parameters :=

The filter is implemented using the class ArrayFilter1DUsingConvolution.

Constructor & Destructor Documentation

SeparableConvolutionImageFilter()

template<typename elemT >

stir::SeparableConvolutionImageFilter< elemT >::SeparableConvolutionImageFilter

(

const VectorWithOffset< VectorWithOffset< elemT >> &

filter_coefficients

)

Constructor taking filter coefficients explicitly.

These filter coefficients are passed to the ArrayFilter1DUsingConvolution constructor.

filter_coefficients has to have length 3. (Start index is irrelevant). Its first element will be applied to the 'first dimension', i.e. the first index.

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

• /home/sirfuser/devel/STIRdistrib/STIR/src/include/stir/SeparableConvolutionImageFilter.h
• /home/sirfuser/devel/STIRdistrib/STIR/src/buildblock/SeparableConvolutionImageFilter.cxx