flgamma.c

来自「image processing including fourier,wavel」· C语言 代码 · 共 38 行

/*--------------------------- MegaWave2 Command -----------------------------*/
/* mwcommand
name = {flgamma};
version = {"1.1"};
author = {"Lionel Moisan"};
function = {"Create a x^gamma signal, 0 <= x/s < n (2-Flist)"};
usage = {   
 'g':[g=2.]->g      "gamma power (default 2.)",
 'n':[n=256]->n     "number of samples (default 256)",
 's':[s=1.]->s      "step on x (default 1.)",
 'f':f->f           "apply scale factor to ensure fixed point : out(f)=f",
 out<-out           "output Flist"
};
*/

#include <stdio.h>
#include <math.h>
#include "mw.h"

Flist flgamma(out,g,s,n,f)
     Flist out;
     float *g,*s,*f;
     int *n;
{
  int i;
  double x,scale;

  out = mw_change_flist(out,*n,*n,2);
  scale = (f?(double)(*f)/pow((double)(*f),(double)(*g)):1.);
  for (i=0;i<*n;i++) {
    x = *s*(float)i;
    out->values[2*i  ] = x;
    out->values[2*i+1] = (float)(scale*pow((double)x,(double)(*g)));
  }

  return(out);
}