tjmap.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 = {tjmap};
version={"1.2"};
author = {"Vicent Caselles, Bartomeu Coll, Jacques Froment, JL Lisani"};
labo = {"Universitat de les Illes Balears and CEREMADE"};
function = {"map the T and X junctions of a cimage"};
usage = {
'c'->connex8 "8-connexity (default : 4)",
'v'->values  "plot in J the pixels values of the junctions",
'a':[tarea=40]->tarea[0,5000] "area threshold",
'q':[tquant=2]->tquant[0,255] "quantization threshold",
U->U "input cimage U",
J<-J "output cimage J : location of the junctions (map)",
ntj<-tjmap "number of junctions found"
        };
*/

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

extern int tjpoint();


/* Record the junction location */

void record_junction(U,J,values,x,y)

Cimage U,J;
char *values;
int x,y;

{
  int l;

  if (!values) mw_plot_cimage(J,x,y,255);
  else
    {
      l=y*U->ncol+x;
      J->gray[l] = U->gray[l];
      J->gray[l+1] = U->gray[l+1];      
      J->gray[l+U->ncol] = U->gray[l+U->ncol];      
      J->gray[l+U->ncol+1] = U->gray[l+U->ncol+1];      
    }
}

int tjmap(connex8,values,tarea,tquant,U,J)

char *connex8;
char *values;
int *tarea;
int *tquant;
Cimage U,J;

{
  int x,y;  /* current position (x,y) */
  int tj,ntj,l;
  unsigned char *M=NULL; /* Tab to mark the pixels in mscarea */
  int *P=NULL;           /* Tab to index area -> pixel in mscarea */

  /* Initialisations */

  J=mw_change_cimage(J, U->nrow, U->ncol);
  if (J==NULL) mwerror(FATAL,1,"Not enough memory.\n");
  mw_clear_cimage(J,0);

  M=(unsigned char *) malloc(U->nrow*U->ncol);
  if (M==NULL) mwerror(FATAL,1,"Not enough memory.\n");
  memset(M,0,U->nrow*U->ncol);
  
  P=(int *) malloc(*tarea * sizeof(int));
  if (P==NULL) mwerror(FATAL,1,"Not enough memory.\n");
  for (l=0; l<*tarea; l++) P[l]=-1;

  /* Scan each point of the image U */

  ntj=0;
  for (y=0; y < U->nrow - 1; y++)
    { 
      mwdebug("line %d/%d...\n",y,U->nrow-2);
      for (x=0; x < U->ncol - 1; x++)
	{
	  tj = tjpoint(connex8,tarea,tquant,U,x,y,
		       NULL,NULL,NULL,NULL,NULL,NULL,M,P);
	  if (tj > 0) { ntj++; record_junction(U,J,values,x,y); }
	}
    }
  free(P);
  free(M);
  return(ntj);
}