#include <stdio.h>


main()
{
	int done = 0,i;
	char ch;
	int harray[256];
	ungetc(0,stdin);
do {
	VIS$LINEARIZE_LUT(i,0);
	VIS$FREEZE(); 
	HISTOGRAM(0,0,640,480,1,harray,2);
	VIS$VIEW();
	delay();    
/*	set_raw_mode();
	scanf("%s",&ch);
	set_normal_mode();
	if (ch==0)
	  ungetc(done,stdin);
	else
	  done = 1; */

   }while (done == 0);
}
HISTOGRAM(x1,y1,x2,y2,equalize,harray, color)
  int x1,y1,x2,y2, equalize, *harray, color;
  {
    int i,x;
    int offset,base,largest,grpfact,barwidth,area,X1,X2;
    int values[641];
    float scale,eos;

    /* CONSTANTS */
    grpfact=4;
    barwidth=8;
    base= 455 /* was 475 RWW */ ;
    area=(y2-y1)*(x2-x1);
    eos=256/grpfact-1;     /* End Of Scale */



    /* INITIALIZE ARRAYS */
    for (i=0;i<=255;i++)
    {
      harray[i] = 0;
    }

    /* FILL HARRAY WITH READ_HORIZONTAL_LINE this is the histogram */
    for (i=y1;i<=y2;i++)
    {
      rhline(x1,i,x2-x1,values);
      for (x=0;x<x2-x1;x++)
        harray[ (values[x] & 0x00ff) ]++;  /* for 8 bits only 0..255 */
     }

  if (equalize)
  {
      equalize_histogram_dave(harray,area);

   }
}


equalize_histogram_dave(harray,area)
int harray[255];
int area;
{
  int values[256];
  float t[255],sum[255],increment,tolerance;
  int i,x,cmdd  ;
  int earray[255]; /* for histogram */

  /* INITIALIZE ARRAYS */
  for (i=0;i<255;i++)
    {
    t[i]=0.0;
    sum[i]=0.0;
    earray[i]=0;
    }

  /* TRANSFORM HARRAY INTO T */
  for (i=0;i<255;i++)
    t[i] = (float)harray[i]/(float)area;

  /* SUMMATION OF T */
  for (i=0;i<255;i++)
    {
    if (i==0)
      sum[i] = t[0];
    else
      sum[i] = sum[i-1] + t[i];
    }
      mapsums(sum,values);
 }


mapsums(sum,values)
int values[256];
float sum[255];
{
 float temp[255];
 int i,x;
 for (i=0;i<255;i++)
 {
    if (i==0)
      temp[i] = 0;
    else
      temp[i] = i*1.0/255.0 + 1/510;        
 }
 for (i=0;i<255;i++)
 {
   x=0;
   while ( temp[x] < sum[i])
	x++;
   values[i] = x;
 
 }
 VIS$LOAD_LUT (0, 14, values);
 VIS$SET_MODE(1);
 VIS$FREEZE();
 VIS$SET_MODE(0);
}

delay()
{
   int i,j;
   for (i=0;i<10000000;i++)
	j = i + i + i;
}