[Mplayer-cvslog] CVS: main/libaf window.c,1.1,1.2

Alex Beregszaszi alex at mplayerhq.hu
Sun Dec 22 17:31:34 CET 2002


Update of /cvsroot/mplayer/main/libaf
In directory mail:/var/tmp.root/cvs-serv1536/libaf

Modified Files:
	window.c 
Log Message:
dos2unix conversion

Index: window.c
===================================================================
RCS file: /cvsroot/mplayer/main/libaf/window.c,v
retrieving revision 1.1
retrieving revision 1.2
diff -u -r1.1 -r1.2
--- window.c	1 Oct 2002 06:45:08 -0000	1.1
+++ window.c	22 Dec 2002 16:31:01 -0000	1.2
@@ -1,203 +1,203 @@
-/*=============================================================================
-//	
-//  This software has been released under the terms of the GNU Public
-//  license. See http://www.gnu.org/copyleft/gpl.html for details.
-//
-//  Copyright 2001 Anders Johansson ajh at atri.curtin.edu.au
-//
-//=============================================================================
-*/
-
-/* Calculates a number of window functions. The following window
-   functions are currently implemented: Boxcar, Triang, Hanning,
-   Hamming, Blackman, Flattop and Kaiser. In the function call n is
-   the number of filter taps and w the buffer in which the filter
-   coefficients will be stored.
-*/
-
-#include <math.h>
-#include "dsp.h"
-
-/*
-// Boxcar
-//
-// n window length
-// w buffer for the window parameters
-*/
-void boxcar(int n, _ftype_t* w)
-{
-  int i;
-  // Calculate window coefficients
-  for (i=0 ; i<n ; i++)
-    w[i] = 1.0;
-}
-
-
-/*
-// Triang a.k.a Bartlett
-//
-//               |    (N-1)| 
-//           2 * |k - -----|
-//               |      2  |
-// w = 1.0 - ---------------
-//                    N+1
-// n window length
-// w buffer for the window parameters
-*/
-void triang(int n, _ftype_t* w)
-{
-  _ftype_t k1  = (_ftype_t)(n & 1);
-  _ftype_t k2  = 1/((_ftype_t)n + k1);
-  int      end = (n + 1) >> 1;
-  int	   i;
-  
-  // Calculate window coefficients
-  for (i=0 ; i<end ; i++)
-    w[i] = w[n-i-1] = (2.0*((_ftype_t)(i+1))-(1.0-k1))*k2;
-}
-
-
-/*
-// Hanning
-//                   2*pi*k
-// w = 0.5 - 0.5*cos(------), where 0 < k <= N
-//                    N+1
-// n window length
-// w buffer for the window parameters
-*/
-void hanning(int n, _ftype_t* w)
-{
-  int	   i;
-  _ftype_t k = 2*M_PI/((_ftype_t)(n+1)); // 2*pi/(N+1)
-  
-  // Calculate window coefficients
-  for (i=0; i<n; i++)
-    *w++ = 0.5*(1.0 - cos(k*(_ftype_t)(i+1)));
-}
-
-/*
-// Hamming
-//                        2*pi*k
-// w(k) = 0.54 - 0.46*cos(------), where 0 <= k < N
-//                         N-1
-//
-// n window length
-// w buffer for the window parameters
-*/
-void hamming(int n,_ftype_t* w)
-{
-  int      i;
-  _ftype_t k = 2*M_PI/((_ftype_t)(n-1)); // 2*pi/(N-1)
-
-  // Calculate window coefficients
-  for (i=0; i<n; i++)
-    *w++ = 0.54 - 0.46*cos(k*(_ftype_t)i);
-}
-
-/*
-// Blackman
-//                       2*pi*k             4*pi*k
-// w(k) = 0.42 - 0.5*cos(------) + 0.08*cos(------), where 0 <= k < N
-//                        N-1                 N-1
-//
-// n window length
-// w buffer for the window parameters
-*/
-void blackman(int n,_ftype_t* w)
-{
-  int      i;
-  _ftype_t k1 = 2*M_PI/((_ftype_t)(n-1)); // 2*pi/(N-1)
-  _ftype_t k2 = 2*k1; // 4*pi/(N-1)
-
-  // Calculate window coefficients
-  for (i=0; i<n; i++)
-    *w++ = 0.42 - 0.50*cos(k1*(_ftype_t)i) + 0.08*cos(k2*(_ftype_t)i);
-}
-
-/*
-// Flattop
-//                                        2*pi*k                     4*pi*k
-// w(k) = 0.2810638602 - 0.5208971735*cos(------) + 0.1980389663*cos(------), where 0 <= k < N
-//                                          N-1                        N-1
-//
-// n window length
-// w buffer for the window parameters
-*/
-void flattop(int n,_ftype_t* w)
-{
-  int      i;
-  _ftype_t k1 = 2*M_PI/((_ftype_t)(n-1)); // 2*pi/(N-1)
-  _ftype_t k2 = 2*k1;                   // 4*pi/(N-1)
-  
-  // Calculate window coefficients
-  for (i=0; i<n; i++)
-    *w++ = 0.2810638602 - 0.5208971735*cos(k1*(_ftype_t)i) + 0.1980389663*cos(k2*(_ftype_t)i);
-}
-
-/* Computes the 0th order modified Bessel function of the first kind.  
-// (Needed to compute Kaiser window) 
-//   
-// y = sum( (x/(2*n))^2 )
-//      n
-*/
-#define BIZ_EPSILON 1E-21 // Max error acceptable 
-
-_ftype_t besselizero(_ftype_t x)
-{ 
-  _ftype_t temp;
-  _ftype_t sum   = 1.0;
-  _ftype_t u     = 1.0;
-  _ftype_t halfx = x/2.0;
-  int      n     = 1;
-
-  do {
-    temp = halfx/(_ftype_t)n;
-    u *=temp * temp;
-    sum += u;
-    n++;
-  } while (u >= BIZ_EPSILON * sum);
-  return(sum);
-}
-
-/*
-// Kaiser
-//
-// n window length
-// w buffer for the window parameters
-// b beta parameter of Kaiser window, Beta >= 1
-//
-// Beta trades the rejection of the low pass filter against the
-// transition width from passband to stop band.  Larger Beta means a
-// slower transition and greater stop band rejection.  See Rabiner and
-// Gold (Theory and Application of DSP) under Kaiser windows for more
-// about Beta.  The following table from Rabiner and Gold gives some
-// feel for the effect of Beta:
-// 
-// All ripples in dB, width of transition band = D*N where N = window
-// length
-// 
-// BETA    D       PB RIP   SB RIP
-// 2.120   1.50  +-0.27      -30
-// 3.384   2.23    0.0864    -40
-// 4.538   2.93    0.0274    -50
-// 5.658   3.62    0.00868   -60
-// 6.764   4.32    0.00275   -70
-// 7.865   5.0     0.000868  -80
-// 8.960   5.7     0.000275  -90
-// 10.056  6.4     0.000087  -100
-*/
-void kaiser(int n, _ftype_t* w, _ftype_t b)
-{
-  _ftype_t tmp;
-  _ftype_t k1  = 1.0/besselizero(b);
-  int	   k2  = 1 - (n & 1);
-  int      end = (n + 1) >> 1;
-  int      i; 
-  
-  // Calculate window coefficients
-  for (i=0 ; i<end ; i++){
-    tmp = (_ftype_t)(2*i + k2) / ((_ftype_t)n - 1.0);
-    w[end-(1&(!k2))+i] = w[end-1-i] = k1 * besselizero(b*sqrt(1.0 - tmp*tmp));
-  }
-}
-
+/*=============================================================================
+//	
+//  This software has been released under the terms of the GNU Public
+//  license. See http://www.gnu.org/copyleft/gpl.html for details.
+//
+//  Copyright 2001 Anders Johansson ajh at atri.curtin.edu.au
+//
+//=============================================================================
+*/
+
+/* Calculates a number of window functions. The following window
+   functions are currently implemented: Boxcar, Triang, Hanning,
+   Hamming, Blackman, Flattop and Kaiser. In the function call n is
+   the number of filter taps and w the buffer in which the filter
+   coefficients will be stored.
+*/
+
+#include <math.h>
+#include "dsp.h"
+
+/*
+// Boxcar
+//
+// n window length
+// w buffer for the window parameters
+*/
+void boxcar(int n, _ftype_t* w)
+{
+  int i;
+  // Calculate window coefficients
+  for (i=0 ; i<n ; i++)
+    w[i] = 1.0;
+}
+
+
+/*
+// Triang a.k.a Bartlett
+//
+//               |    (N-1)| 
+//           2 * |k - -----|
+//               |      2  |
+// w = 1.0 - ---------------
+//                    N+1
+// n window length
+// w buffer for the window parameters
+*/
+void triang(int n, _ftype_t* w)
+{
+  _ftype_t k1  = (_ftype_t)(n & 1);
+  _ftype_t k2  = 1/((_ftype_t)n + k1);
+  int      end = (n + 1) >> 1;
+  int	   i;
+  
+  // Calculate window coefficients
+  for (i=0 ; i<end ; i++)
+    w[i] = w[n-i-1] = (2.0*((_ftype_t)(i+1))-(1.0-k1))*k2;
+}
+
+
+/*
+// Hanning
+//                   2*pi*k
+// w = 0.5 - 0.5*cos(------), where 0 < k <= N
+//                    N+1
+// n window length
+// w buffer for the window parameters
+*/
+void hanning(int n, _ftype_t* w)
+{
+  int	   i;
+  _ftype_t k = 2*M_PI/((_ftype_t)(n+1)); // 2*pi/(N+1)
+  
+  // Calculate window coefficients
+  for (i=0; i<n; i++)
+    *w++ = 0.5*(1.0 - cos(k*(_ftype_t)(i+1)));
+}
+
+/*
+// Hamming
+//                        2*pi*k
+// w(k) = 0.54 - 0.46*cos(------), where 0 <= k < N
+//                         N-1
+//
+// n window length
+// w buffer for the window parameters
+*/
+void hamming(int n,_ftype_t* w)
+{
+  int      i;
+  _ftype_t k = 2*M_PI/((_ftype_t)(n-1)); // 2*pi/(N-1)
+
+  // Calculate window coefficients
+  for (i=0; i<n; i++)
+    *w++ = 0.54 - 0.46*cos(k*(_ftype_t)i);
+}
+
+/*
+// Blackman
+//                       2*pi*k             4*pi*k
+// w(k) = 0.42 - 0.5*cos(------) + 0.08*cos(------), where 0 <= k < N
+//                        N-1                 N-1
+//
+// n window length
+// w buffer for the window parameters
+*/
+void blackman(int n,_ftype_t* w)
+{
+  int      i;
+  _ftype_t k1 = 2*M_PI/((_ftype_t)(n-1)); // 2*pi/(N-1)
+  _ftype_t k2 = 2*k1; // 4*pi/(N-1)
+
+  // Calculate window coefficients
+  for (i=0; i<n; i++)
+    *w++ = 0.42 - 0.50*cos(k1*(_ftype_t)i) + 0.08*cos(k2*(_ftype_t)i);
+}
+
+/*
+// Flattop
+//                                        2*pi*k                     4*pi*k
+// w(k) = 0.2810638602 - 0.5208971735*cos(------) + 0.1980389663*cos(------), where 0 <= k < N
+//                                          N-1                        N-1
+//
+// n window length
+// w buffer for the window parameters
+*/
+void flattop(int n,_ftype_t* w)
+{
+  int      i;
+  _ftype_t k1 = 2*M_PI/((_ftype_t)(n-1)); // 2*pi/(N-1)
+  _ftype_t k2 = 2*k1;                   // 4*pi/(N-1)
+  
+  // Calculate window coefficients
+  for (i=0; i<n; i++)
+    *w++ = 0.2810638602 - 0.5208971735*cos(k1*(_ftype_t)i) + 0.1980389663*cos(k2*(_ftype_t)i);
+}
+
+/* Computes the 0th order modified Bessel function of the first kind.  
+// (Needed to compute Kaiser window) 
+//   
+// y = sum( (x/(2*n))^2 )
+//      n
+*/
+#define BIZ_EPSILON 1E-21 // Max error acceptable 
+
+_ftype_t besselizero(_ftype_t x)
+{ 
+  _ftype_t temp;
+  _ftype_t sum   = 1.0;
+  _ftype_t u     = 1.0;
+  _ftype_t halfx = x/2.0;
+  int      n     = 1;
+
+  do {
+    temp = halfx/(_ftype_t)n;
+    u *=temp * temp;
+    sum += u;
+    n++;
+  } while (u >= BIZ_EPSILON * sum);
+  return(sum);
+}
+
+/*
+// Kaiser
+//
+// n window length
+// w buffer for the window parameters
+// b beta parameter of Kaiser window, Beta >= 1
+//
+// Beta trades the rejection of the low pass filter against the
+// transition width from passband to stop band.  Larger Beta means a
+// slower transition and greater stop band rejection.  See Rabiner and
+// Gold (Theory and Application of DSP) under Kaiser windows for more
+// about Beta.  The following table from Rabiner and Gold gives some
+// feel for the effect of Beta:
+// 
+// All ripples in dB, width of transition band = D*N where N = window
+// length
+// 
+// BETA    D       PB RIP   SB RIP
+// 2.120   1.50  +-0.27      -30
+// 3.384   2.23    0.0864    -40
+// 4.538   2.93    0.0274    -50
+// 5.658   3.62    0.00868   -60
+// 6.764   4.32    0.00275   -70
+// 7.865   5.0     0.000868  -80
+// 8.960   5.7     0.000275  -90
+// 10.056  6.4     0.000087  -100
+*/
+void kaiser(int n, _ftype_t* w, _ftype_t b)
+{
+  _ftype_t tmp;
+  _ftype_t k1  = 1.0/besselizero(b);
+  int	   k2  = 1 - (n & 1);
+  int      end = (n + 1) >> 1;
+  int      i; 
+  
+  // Calculate window coefficients
+  for (i=0 ; i<end ; i++){
+    tmp = (_ftype_t)(2*i + k2) / ((_ftype_t)n - 1.0);
+    w[end-(1&(!k2))+i] = w[end-1-i] = k1 * besselizero(b*sqrt(1.0 - tmp*tmp));
+  }
+}
+




More information about the MPlayer-cvslog mailing list