fdiff.c

image processing including fourier,wavelet,segmentation etc.

/* ---------------- M E G A W A V E 2  h e a d e r ------------------------- */
/* mwcommand
 name = {fdiff};
 author = {"Jacques Froment"};
 function = {"Computes the difference between pixel's gray-levels of two fimages"};
 version = {"1.00"};
 usage = {
 'a'->absd  "flag to compute the absolute difference",
 A->A       "input fimage A", 
 B->B       "input fimage B", 
 O<-O       "output O=A-B"
};
*/
/* ------------------------------------------------------------------------- */

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

void fdiff(absd,A,B,O)

char *absd;
Fimage	A,B,O;

{
  long l;
  long	dx, dy;		/* Size of image */
  register float *ptr1,*ptr2,*ptr3;
  register int i;

  if((A->nrow != B->nrow) || (A->ncol != B->ncol))
    mwerror(FATAL, 1, "Image1 and Image2 have not the same size!\n");

  dx = A->ncol;
  dy = A->nrow;
  if ((O = mw_change_fimage(O,dy,dx)) == NULL)
    mwerror(FATAL, 1, "Not enough memory\n");  

  l = dx*dy;
  if (absd)
    for (ptr1=A->gray, ptr2=B->gray, ptr3=O->gray, i=0;
	 i < dx*dy; ptr1++, ptr2++, ptr3++, i++)
      *ptr3 = fabs((double) *ptr1 - *ptr2);
  else
    for (ptr1=A->gray, ptr2=B->gray, ptr3=O->gray, i=0;
	 i < dx*dy; ptr1++, ptr2++, ptr3++, i++)
      *ptr3 = *ptr1 - *ptr2;

  /*  
  strcpy(O->cmt, "Absolute diff. of ");
  strcat(O->cmt, A->name);
  strcat(O->cmt, " and ");
  strcat(O->cmt, B->name);
  */
}