KaiserBessel Class Reference

1-D Kaiser-Bessel window function class. More...

#include <util_sparx.h>

Inheritance diagram for KaiserBessel:

Collaboration diagram for KaiserBessel:

List of all members.

Public Member Functions

KaiserBessel (float alpha_, int K, float r_, float v_, int N_, float vtable_=0.f, int ntable_=5999)

virtual ~KaiserBessel ()

float I0table_maxerror ()

Compute the maximum error in the table.

vector< float > dump_table ()

virtual float sinhwin (float x) const

Kaiser-Bessel Sinh window function.

virtual float i0win (float x) const

Kaiser-Bessel I0 window function.

float i0win_tab (float x) const

Kaiser-Bessel I0 window function (uses table lookup).

int get_window_size () const

Return the size of the I0 window.

kbsinh_win get_kbsinh_win ()

Sinh window function object factory.

kbi0_win get_kbi0_win ()

I0 window function object factory.

Protected Member Functions

virtual void build_I0table ()

2*pi*alpha*r*vadjust

Protected Attributes

float alpha

float v

float r

int N

Kaiser-Bessel parameters.

int K

size in Ix-space

float vtable

I0 window size.

int ntable

table I0 non-zero domain maximum

vector< float > i0table

float dtable

float alphar

table spacing

float fac

alpha*r

float vadjust

2*pi*alpha*r*v

float facadj

float fltb

Tabulate I0 window for speed.

Classes

class kbi0_win

I0 window function object. More...

class kbsinh_win

Sinh window function object. More...

Detailed Description

1-D Kaiser-Bessel window function class.

(It's a class so that the windowing parameters may be instantiated and held in the instance object.)

The I0 version can be tabulated and interpolated upon demand, but the max error needs to be checked. The "vtable" parameter corresponds to the maximum value of x for which the I0 window is non-zero. Setting "vtable" different from "v" corresponds to a change in units of x. In practice, it is often handy to replace x in some sort of absolute units with x described in terms of grid intervals.

The get_kbsinh_win and get_kbi0_win functions return single-argument function objects, which is what a generic routine is likely to want.

See also:: P. A. Penczek, R. Renka, and H. Schomberg, J. Opt. Soc. Am. _21_, 449 (2004)

Definition at line 189 of file util_sparx.h.

Constructor & Destructor Documentation

KaiserBessel::KaiserBessel	(	float	alpha_,
		int	K,
		float	r_,
		float	v_,
		int	N_,
		float	vtable_ = `0.f`,
		int	ntable_ = `5999`
	)

virtual KaiserBessel::~KaiserBessel ( ) [inline, virtual]

Definition at line 209 of file util_sparx.h.

00209 {};

Member Function Documentation

virtual void KaiserBessel::build_I0table ( ) [protected, virtual]

2*pi*alpha*r*vadjust

Reimplemented in FakeKaiserBessel.

float KaiserBessel::I0table_maxerror ( )

Compute the maximum error in the table.

vector<float> KaiserBessel::dump_table ( ) [inline]

Definition at line 212 of file util_sparx.h.

References i0table.

00212                                            {
00213                         return i0table;
00214                 }

virtual float KaiserBessel::sinhwin ( float x ) const [virtual]

Kaiser-Bessel Sinh window function.

Reimplemented in FakeKaiserBessel.

Referenced by KaiserBessel::kbsinh_win::operator()().

virtual float KaiserBessel::i0win ( float x ) const [virtual]

Kaiser-Bessel I0 window function.

Reimplemented in FakeKaiserBessel.

Referenced by KaiserBessel::kbi0_win::operator()().

float KaiserBessel::i0win_tab ( float x ) const [inline]

Kaiser-Bessel I0 window function (uses table lookup).

Definition at line 220 of file util_sparx.h.

References fltb, and i0table.

00220                                                       {
00221                 /*float absx = fabs(x);
00222                         int loc = int(round(absx*fltb));
00223                         return i0table[loc];*/
00224                         float xt;
00225                         if(x<0.f) xt = -x*fltb+0.5f; else xt = x*fltb+0.5f;
00226                         return i0table[ (int) xt];
00227                         /*return i0table[ (int) (fabs(x)*fltb+0.5f)];
00228                                 if (absx > vtable) return 0.f;
00229                                 float loc = absx/dtable;
00230                                 return i0table[int(loc + 0.5f)]; */
00231                 }

int KaiserBessel::get_window_size ( ) const [inline]

Return the size of the I0 window.

Definition at line 233 of file util_sparx.h.

References K.

Referenced by KaiserBessel::kbi0_win::get_window_size(), and KaiserBessel::kbsinh_win::get_window_size().

00233 { return K; }

kbsinh_win KaiserBessel::get_kbsinh_win ( ) [inline]

Sinh window function object factory.

Definition at line 245 of file util_sparx.h.

00245                                             {
00246                         return kbsinh_win(*this);
00247                 }

kbi0_win KaiserBessel::get_kbi0_win ( ) [inline]

I0 window function object factory.

Definition at line 259 of file util_sparx.h.

00259                                         {
00260                         return kbi0_win(*this);
00261                 }

Member Data Documentation

float KaiserBessel::alpha [protected]

Definition at line 192 of file util_sparx.h.

float KaiserBessel::v [protected]

Definition at line 192 of file util_sparx.h.

float KaiserBessel::r [protected]

Definition at line 192 of file util_sparx.h.

int KaiserBessel::N [protected]

Kaiser-Bessel parameters.

Definition at line 193 of file util_sparx.h.

int KaiserBessel::K [protected]

size in Ix-space

Definition at line 194 of file util_sparx.h.

Referenced by get_window_size().

float KaiserBessel::vtable [protected]

I0 window size.

Definition at line 195 of file util_sparx.h.

int KaiserBessel::ntable [protected]

table I0 non-zero domain maximum

Definition at line 196 of file util_sparx.h.

vector<float> KaiserBessel::i0table [protected]

Definition at line 197 of file util_sparx.h.

Referenced by dump_table(), and i0win_tab().

float KaiserBessel::dtable [protected]

Definition at line 198 of file util_sparx.h.

float KaiserBessel::alphar [protected]

table spacing

Definition at line 199 of file util_sparx.h.

float KaiserBessel::fac [protected]

alpha*r

Definition at line 200 of file util_sparx.h.

float KaiserBessel::vadjust [protected]

2*pi*alpha*r*v

Definition at line 201 of file util_sparx.h.

float KaiserBessel::facadj [protected]

Definition at line 202 of file util_sparx.h.

float KaiserBessel::fltb [protected]

Tabulate I0 window for speed.

Definition at line 204 of file util_sparx.h.

Referenced by i0win_tab().

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

util_sparx.h


Public Member Functions
	KaiserBessel (float alpha_, int K, float r_, float v_, int N_, float vtable_=0.f, int ntable_=5999)
virtual	~KaiserBessel ()
float	I0table_maxerror ()
	Compute the maximum error in the table.
vector< float >	dump_table ()
virtual float	sinhwin (float x) const
	Kaiser-Bessel Sinh window function.
virtual float	i0win (float x) const
	Kaiser-Bessel I0 window function.
float	i0win_tab (float x) const
	Kaiser-Bessel I0 window function (uses table lookup).
int	get_window_size () const
	Return the size of the I0 window.
kbsinh_win	get_kbsinh_win ()
	Sinh window function object factory.
kbi0_win	get_kbi0_win ()
	I0 window function object factory.
Protected Member Functions
virtual void	build_I0table ()
	2pialpharvadjust
Protected Attributes
float	alpha
float	v
float	r
int	N
	Kaiser-Bessel parameters.
int	K
	size in Ix-space
float	vtable
	I0 window size.
int	ntable
	table I0 non-zero domain maximum
vector< float >	i0table
float	dtable
float	alphar
	table spacing
float	fac
	alpha*r
float	vadjust
	2pialpharv
float	facadj
float	fltb
	Tabulate I0 window for speed.
Classes
class	kbi0_win
	I0 window function object. More...
class	kbsinh_win
	Sinh window function object. More...