#include <util.h>
Inheritance diagram for EMAN::Util::KaiserBessel:
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... |
(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.
Definition at line 311 of file util.h.
Util::KaiserBessel::KaiserBessel | ( | float | alpha_, | |
int | K, | |||
float | r_, | |||
float | v_, | |||
int | N_, | |||
float | vtable_ = 0.f , |
|||
int | ntable_ = 5999 | |||
) |
Definition at line 1988 of file util_sparx.cpp.
References alpha, alphar, build_I0table(), fac, facadj, K, r, twopi, v, vadjust, and vtable.
01990 : alpha(alpha_), v(v_), r(r_), N(N_), K(K_), vtable(vtable_), 01991 ntable(ntable_) { 01992 // Default values are alpha=1.25, K=6, r=0.5, v = K/2 01993 if (0.f == v) v = float(K)/2; 01994 if (0.f == vtable) vtable = v; 01995 alphar = alpha*r; 01996 fac = static_cast<float>(twopi)*alphar*v; 01997 vadjust = 1.0f*v; 01998 facadj = static_cast<float>(twopi)*alphar*vadjust; 01999 build_I0table(); 02000 }
virtual EMAN::Util::KaiserBessel::~KaiserBessel | ( | ) | [inline, virtual] |
void Util::KaiserBessel::build_I0table | ( | ) | [protected, virtual] |
2*pi*alpha*r*vadjust
Reimplemented in EMAN::Util::FakeKaiserBessel.
Definition at line 2011 of file util_sparx.cpp.
References facadj, fltb, i0table, K, N, ntable, EMAN::Util::round(), sqrt(), and vadjust.
Referenced by KaiserBessel().
02011 { 02012 i0table.resize(ntable+1); // i0table[0:ntable] 02013 int ltab = int(round(float(ntable)/1.25f)); 02014 fltb = float(ltab)/(K/2); 02015 float val0 = static_cast<float>(gsl_sf_bessel_I0(facadj)); 02016 for (int i=ltab+1; i <= ntable; i++) i0table[i] = 0.f; 02017 for (int i=0; i <= ltab; i++) { 02018 float s = float(i)/fltb/N; 02019 if (s < vadjust) { 02020 float rt = sqrt(1.f - pow(s/vadjust, 2)); 02021 i0table[i] = static_cast<float>(gsl_sf_bessel_I0(facadj*rt))/val0; 02022 } else { 02023 i0table[i] = 0.f; 02024 } 02025 // cout << " "<<s*N<<" "<<i0table[i] <<endl; 02026 } 02027 }
vector<float> EMAN::Util::KaiserBessel::dump_table | ( | ) | [inline] |
kbi0_win EMAN::Util::KaiserBessel::get_kbi0_win | ( | ) | [inline] |
kbsinh_win EMAN::Util::KaiserBessel::get_kbsinh_win | ( | ) | [inline] |
int EMAN::Util::KaiserBessel::get_window_size | ( | ) | const [inline] |
Return the size of the I0 window.
Definition at line 355 of file util.h.
Referenced by EMAN::Util::get_pixel_conv_new(), and EMAN::Util::get_pixel_conv_new_background().
float Util::KaiserBessel::I0table_maxerror | ( | ) |
Compute the maximum error in the table.
Definition at line 2029 of file util_sparx.cpp.
References i0table, and ntable.
02029 { 02030 float maxdiff = 0.f; 02031 for (int i = 1; i <= ntable; i++) { 02032 float diff = fabs(i0table[i] - i0table[i-1]); 02033 if (diff > maxdiff) maxdiff = diff; 02034 } 02035 return maxdiff; 02036 }
float Util::KaiserBessel::i0win | ( | float | x | ) | const [virtual] |
Kaiser-Bessel I0 window function.
Reimplemented in EMAN::Util::FakeKaiserBessel.
Definition at line 2002 of file util_sparx.cpp.
References facadj, sqrt(), and vadjust.
Referenced by EMAN::Processor::EMFourierFilterFunc().
02002 { 02003 float val0 = float(gsl_sf_bessel_I0(facadj)); 02004 float absx = fabs(x); 02005 if (absx > vadjust) return 0.f; 02006 float rt = sqrt(1.f - pow(absx/vadjust, 2)); 02007 float res = static_cast<float>(gsl_sf_bessel_I0(facadj*rt))/val0; 02008 return res; 02009 }
float EMAN::Util::KaiserBessel::i0win_tab | ( | float | x | ) | const [inline] |
Kaiser-Bessel I0 window function (uses table lookup).
Definition at line 342 of file util.h.
Referenced by EMAN::Util::extractpoint2(), EMAN::Util::get_pixel_conv_new(), and EMAN::Util::get_pixel_conv_new_background().
float Util::KaiserBessel::sinhwin | ( | float | x | ) | const [virtual] |
Kaiser-Bessel Sinh window function.
Reimplemented in EMAN::Util::FakeKaiserBessel.
Definition at line 2038 of file util_sparx.cpp.
References alphar, fac, and sqrt().
Referenced by EMAN::Processor::EMFourierFilterFunc().
02038 { 02039 float val0 = sinh(fac)/fac; 02040 float absx = fabs(x); 02041 if (0.0 == x) { 02042 float res = 1.0f; 02043 return res; 02044 } else if (absx == alphar) { 02045 return 1.0f/val0; 02046 } else if (absx < alphar) { 02047 float rt = sqrt(1.0f - pow((x/alphar), 2)); 02048 float facrt = fac*rt; 02049 float res = (sinh(facrt)/facrt)/val0; 02050 return res; 02051 } else { 02052 float rt = sqrt(pow((x/alphar),2) - 1.f); 02053 float facrt = fac*rt; 02054 float res = (sin(facrt)/facrt)/val0; 02055 return res; 02056 } 02057 }
float EMAN::Util::KaiserBessel::alpha [protected] |
float EMAN::Util::KaiserBessel::alphar [protected] |
table spacing
Definition at line 321 of file util.h.
Referenced by KaiserBessel(), EMAN::Util::FakeKaiserBessel::sinhwin(), and sinhwin().
float EMAN::Util::KaiserBessel::dtable [protected] |
float EMAN::Util::KaiserBessel::fac [protected] |
alpha*r
Definition at line 322 of file util.h.
Referenced by KaiserBessel(), EMAN::Util::FakeKaiserBessel::sinhwin(), and sinhwin().
float EMAN::Util::KaiserBessel::facadj [protected] |
Definition at line 324 of file util.h.
Referenced by EMAN::Util::FakeKaiserBessel::build_I0table(), build_I0table(), EMAN::Util::FakeKaiserBessel::i0win(), i0win(), and KaiserBessel().
float EMAN::Util::KaiserBessel::fltb [protected] |
Tabulate I0 window for speed.
Definition at line 326 of file util.h.
Referenced by EMAN::Util::FakeKaiserBessel::build_I0table(), and build_I0table().
vector<float> EMAN::Util::KaiserBessel::i0table [protected] |
Definition at line 319 of file util.h.
Referenced by EMAN::Util::FakeKaiserBessel::build_I0table(), build_I0table(), and I0table_maxerror().
int EMAN::Util::KaiserBessel::K [protected] |
size in Ix-space
Definition at line 316 of file util.h.
Referenced by EMAN::Util::FakeKaiserBessel::build_I0table(), build_I0table(), and KaiserBessel().
int EMAN::Util::KaiserBessel::N [protected] |
Kaiser-Bessel parameters.
Definition at line 315 of file util.h.
Referenced by EMAN::Util::FakeKaiserBessel::build_I0table(), and build_I0table().
int EMAN::Util::KaiserBessel::ntable [protected] |
table I0 non-zero domain maximum
Definition at line 318 of file util.h.
Referenced by EMAN::Util::FakeKaiserBessel::build_I0table(), build_I0table(), and I0table_maxerror().
float EMAN::Util::KaiserBessel::r [protected] |
float EMAN::Util::KaiserBessel::v [protected] |
float EMAN::Util::KaiserBessel::vadjust [protected] |
2*pi*alpha*r*v
Definition at line 323 of file util.h.
Referenced by EMAN::Util::FakeKaiserBessel::build_I0table(), build_I0table(), EMAN::Util::FakeKaiserBessel::i0win(), i0win(), and KaiserBessel().
float EMAN::Util::KaiserBessel::vtable [protected] |