Abstract base class for all back projectors. More...

#include "stir/recon_buildblock/BackProjectorByBin.h"

Inheritance diagram for stir::BackProjectorByBin:

[legend]

Public Member Functions
	BackProjectorByBin ()
	Default constructor calls reset_timers()

virtual void	set_up (const shared_ptr< const ProjDataInfo > &proj_data_info_ptr, const shared_ptr< const DiscretisedDensity< 3, float >> &density_info_sptr)=0
	Stores all necessary geometric info. More...

virtual const DataSymmetriesForViewSegmentNumbers *	get_symmetries_used () const =0
	Informs on which symmetries the projector handles It should get data related by at least those symmetries. Otherwise, a run-time error will occur (unless the derived class has other behaviour).

void	back_project (DiscretisedDensity< 3, float > &, const ProjData &, int subset_num=0, int num_subsets=1)
	project whole proj_data into the volume More...

virtual void	back_project (const ProjData &, int subset_num=0, int num_subsets=1)
	projects the viewgrams into the volume it adds to the data backprojected since start_accumulating_in_new_target() was last called.

void	back_project (const RelatedViewgrams< float > &)
	projects the viewgrams into the volume it adds to the data backprojected since start_accumulating_in_new_target() was last called.

void	back_project (const RelatedViewgrams< float > &, const int min_axial_pos_num, const int max_axial_pos_num)
	projects the specified range of the viewgrams and axial positions into the volume it adds to the data backprojected since start_accumulating_in_new_target() was last called.

void	back_project (const RelatedViewgrams< float > &, const int min_axial_pos_num, const int max_axial_pos_num, const int min_tangential_pos_num, const int max_tangential_pos_num)
	projects the specified range of the viewgrams, axial positions and tangential positions into the volume it adds to the data backprojected since start_accumulating_in_new_target() was last called.

virtual void	start_accumulating_in_new_target ()
	tell the back projector to start accumulating into a new target. This function has to be called before any back-projection is initiated.

virtual void	get_output (DiscretisedDensity< 3, float > &) const
	Get output This will overwrite the array-content of the argument with the result of all backprojections since calling `start_accumulating_in_new_target()`. Note that the argument has to have the same characteristics as what was used when calling `set_up()`.

void	set_post_data_processor (shared_ptr< DataProcessor< DiscretisedDensity< 3, float >>> post_data_processor_sptr)
	Set data processor to use after back projection.

virtual BackProjectorByBin *	clone () const =0

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)

Public Member Functions inherited from stir::RegisteredObjectBase
virtual std::string	get_registered_name () const =0
	Returns the name of the type of the object. More...

Public Member Functions inherited from stir::ParsingObject
	ParsingObject (const ParsingObject &)

ParsingObject &	operator= (const ParsingObject &)

void	ask_parameters ()

virtual std::string	parameter_info ()

bool	parse (std::istream &f)

bool	parse (const char *const filename)

Protected Member Functions
virtual void	actual_back_project (DiscretisedDensity< 3, float > &, const RelatedViewgrams< float > &, const int min_axial_pos_num, const int max_axial_pos_num, const int min_tangential_pos_num, const int max_tangential_pos_num)
	This actually does the back projection. There are two versions of this code to enable backwards compatibility. More...

virtual void	actual_back_project (const RelatedViewgrams< float > &, const int min_axial_pos_num, const int max_axial_pos_num, const int min_tangential_pos_num, const int max_tangential_pos_num)
	This actually does the back projection. There are two versions of this code to enable backwards compatibility. More...

virtual void	check (const ProjDataInfo &proj_data_info) const
	check if the argument is the same as what was used for set_up() More...

virtual void	check (const ProjDataInfo &proj_data_info, const DiscretisedDensity< 3, float > &density_info) const
	check if the arguments are the same as what was used for set_up() More...

void	set_defaults () override
	Set defaults before parsing.

void	initialise_keymap () override
	Initialise all keywords.

Protected Member Functions inherited from stir::ParsingObject
virtual bool	post_processing ()
	This will be called at the end of the parsing. More...

virtual void	set_key_values ()
	This will be called before parsing or parameter_info is called. More...

Protected Attributes
bool	_already_set_up

shared_ptr< DiscretisedDensity< 3, float > >	_density_sptr
	Clone of the density sptr set with set_up()

shared_ptr< DataProcessor< DiscretisedDensity< 3, float > > >	_post_data_processor_sptr

shared_ptr< const ProjDataInfo >	_proj_data_info_sptr
	ProjDataInfo set by set_up()

Protected Attributes inherited from stir::ParsingObject
KeyParser	parser

Additional Inherited Members
Static Public Member Functions inherited from stir::RegisteredObject< BackProjectorByBin >
static BackProjectorByBin *	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 BackProjectorByBin *	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< BackProjectorByBin >
typedef BackProjectorByBin (	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.

Static Protected Member Functions inherited from stir::RegisteredObject< BackProjectorByBin >
static RegistryType &	registry ()
	Static function returning the registry. More...

Detailed Description

Abstract base class for all back projectors.

Member Function Documentation

◆ set_up()

void stir::BackProjectorByBin::set_up	(	const shared_ptr< const ProjDataInfo > &	proj_data_info_ptr,
		const shared_ptr< const DiscretisedDensity< 3, float >> &	density_info_sptr
	)

pure virtual

Stores all necessary geometric info.

If necessary, set_up() can be called more than once.

Derived classes can assume that back_project() will be called with input corresponding to the arguments of the last call to set_up().

Warning: there is currently no check on this.; Derived classes have to call set_up from the base class.

Implemented in stir::BackProjectorByBinUsingInterpolation, stir::BackProjectorByBinNiftyPET, stir::PostsmoothingBackProjectorByBin, stir::BackProjectorByBinUsingProjMatrixByBin, stir::BackProjectorByBinParallelproj, and stir::BackProjectorByBinUsingSquareProjMatrixByBin.

References _density_sptr, and _proj_data_info_sptr.

Referenced by stir::BackProjectorByBinUsingInterpolation::BackProjectorByBinUsingInterpolation(), stir::BackProjectorByBinUsingSquareProjMatrixByBin::set_up(), stir::BackProjectorByBinParallelproj::set_up(), stir::BackProjectorByBinUsingProjMatrixByBin::set_up(), stir::BackProjectorByBinNiftyPET::set_up(), and stir::BackProjectorByBinUsingInterpolation::set_up().

◆ back_project()

void stir::BackProjectorByBin::back_project	(	DiscretisedDensity< 3, float > &	image,
		const ProjData &	proj_data,
		int	subset_num = `0`,
		int	num_subsets = `1`
	)

project whole proj_data into the volume

it overwrites the data already present in the volume.

The optional arguments can be used to back-project only a subset of the data. Subsets are determined as per detail::find_basic_vs_nums_in_subset(). However, this usage will likely be phased out at later stage.

References actual_back_project(), stir::RelatedViewgrams< elemT >::begin(), check(), stir::RelatedViewgrams< elemT >::end(), stir::error(), stir::DataSymmetriesForViewSegmentNumbers::find_basic_view_segment_numbers(), stir::RelatedViewgrams< elemT >::get_basic_view_segment_num(), stir::RelatedViewgrams< elemT >::get_num_viewgrams(), get_output(), stir::RelatedViewgrams< elemT >::get_proj_data_info_sptr(), get_symmetries_used(), start_accumulating_in_new_target(), and stir::SegmentIndices::timing_pos_num().

Referenced by back_project(), and stir::BackProjectorByBinParallelproj::get_symmetries_used().

◆ actual_back_project() [1/2]

void stir::BackProjectorByBin::actual_back_project	(	DiscretisedDensity< 3, float > &	,
		const RelatedViewgrams< float > &	,
		const int	min_axial_pos_num,
		const int	max_axial_pos_num,
		const int	min_tangential_pos_num,
		const int	max_tangential_pos_num
	)

protectedvirtual

This actually does the back projection. There are two versions of this code to enable backwards compatibility.

This is the older version (in which the backprojected image is not a member variable). In most cases, the new version (in which the backprojected image is a member variable) calls the old version.

If you are developing your own projector, one of these two needs to be overloaded. It doesn't matter which, but it might as well be the new one in case we one day decide to remove the old ones.

Reimplemented in stir::BackProjectorByBinUsingProjMatrixByBin, and stir::BackProjectorByBinUsingSquareProjMatrixByBin.

References stir::error().

Referenced by actual_back_project(), and back_project().

◆ actual_back_project() [2/2]

void stir::BackProjectorByBin::actual_back_project	(	const RelatedViewgrams< float > &	viewgrams,
		const int	min_axial_pos_num,
		const int	max_axial_pos_num,
		const int	min_tangential_pos_num,
		const int	max_tangential_pos_num
	)

protectedvirtual

This actually does the back projection. There are two versions of this code to enable backwards compatibility.

This is the newer version (in which the backprojected image is a member variable). In most cases, the new version calls the old version (in which the backprojected image is not a member variable).

If you are developing your own projector, one of these two needs to be overloaded. It doesn't matter which, but it might as well be the new one in case we one day decide to remove the old ones.

Reimplemented in stir::BackProjectorByBinParallelproj, and stir::BackProjectorByBinNiftyPET.

References _density_sptr, and actual_back_project().

◆ check() [1/2]

void stir::BackProjectorByBin::check ( const ProjDataInfo & proj_data_info ) const

protectedvirtual

check if the argument is the same as what was used for set_up()

calls error() if anything is wrong.

If overriding this function in a derived class, you need to call this one.

References _proj_data_info_sptr, stir::error(), and stir::ProjDataInfo::parameter_info().

Referenced by stir::BinNormalisation::apply(), back_project(), check(), stir::BackProjectorByBinParallelproj::set_up(), stir::BackProjectorByBinNiftyPET::set_up(), and stir::BinNormalisation::undo().

◆ check() [2/2]

void stir::BackProjectorByBin::check	(	const ProjDataInfo &	proj_data_info,
		const DiscretisedDensity< 3, float > &	density_info
	)		const

protectedvirtual

check if the arguments are the same as what was used for set_up()

calls error() if anything is wrong.

If overriding this function in a derived class, you need to call this one.

Calls check(const ProjDataInfo&)

References _density_sptr, check(), and stir::error().

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

/home/sirfuser/devel/STIRdistrib/STIR/src/include/stir/recon_buildblock/BackProjectorByBin.h
/home/sirfuser/devel/STIRdistrib/STIR/src/recon_buildblock/BackProjectorByBin.cxx

Public Member Functions

Protected Member Functions

Protected Attributes

Additional Inherited Members

Detailed Description

Member Function Documentation

◆ set_up()

◆ back_project()

◆ actual_back_project() [1/2]

◆ actual_back_project() [2/2]

◆ check() [1/2]

◆ check() [2/2]