#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include "fitsio.h"

#define LINEPIX 2100
#define LINEPIY 1800

void printerror( int status );

int main(int argc, char *argv[])
{
  fitsfile *fp;
  int i,j,status,nfound,anynull,bitpix=-32;
  long fpixel, nelements,naxis=2;
  long naxes[2]={LINEPIX, LINEPIY},nbuffer,nj;
  float nullval;
  static float buffer[LINEPIX],z[LINEPIY][LINEPIX],s[LINEPIY][LINEPIX];
  int k,nrej;
  double zsum[200],ssum[200],zav,zsg,zs,z2s,lev;

  if(argc!=5){
    fprintf(stderr,"Usage : %s input_file ref_file output_file level\n",argv[0]);
    exit(0);
  }
  sscanf(argv[4],"%lf",&lev);

  fprintf(stderr,"Read %s  ... ",argv[1]);
  status=0;
  if(fits_open_file(&fp,argv[1], READONLY, &status))
    printerror(status);
  if(fits_read_keys_lng(fp, "NAXIS", 1, 2, naxes, &nfound, &status))
    printerror(status);
  fprintf(stderr,"%ld x %ld format ",naxes[0],naxes[1]);
  if((naxes[0]>LINEPIX)||(naxes[1]!=LINEPIY)){
    fprintf(stderr,"\nIllegal image format\n");
    exit(0);
  }
  fpixel = 1;
  nullval = 0;
  nbuffer = naxes[0];
  for(i=0;i<naxes[1];i++){
    if (fits_read_img(fp, TFLOAT, fpixel, nbuffer, &nullval,
                      buffer, &anynull, &status))
      printerror(status);
    for(j=0;j<naxes[0];j++) z[i][j]=buffer[j];
    fpixel+=naxes[0];
  }
  if(fits_close_file(fp, &status))
    printerror(status);
  fprintf(stderr,"OK\n");
  nj=naxes[0];

  fprintf(stderr,"Read %s  ... ",argv[2]);
  status=0;
  if(fits_open_file(&fp,argv[2], READONLY, &status))
    printerror(status);
  if(fits_read_keys_lng(fp, "NAXIS", 1, 2, naxes, &nfound, &status))
    printerror(status);
  fprintf(stderr,"%ld x %ld format ",naxes[0],naxes[1]);
  if((naxes[0]>LINEPIX)||(naxes[1]!=LINEPIY)){
    fprintf(stderr,"\nIllegal image format\n");
    exit(0);
  }
  fpixel = 1;
  nullval = 0;
  nbuffer = naxes[0];
  for(i=0;i<naxes[1];i++){
    if (fits_read_img(fp, TFLOAT, fpixel, nbuffer, &nullval,
                      buffer, &anynull, &status))
      printerror(status);
    for(j=0;j<naxes[0];j++) s[i][j]=buffer[j];
    fpixel+=naxes[0];
  }
  if(fits_close_file(fp, &status))
    printerror(status);
  fprintf(stderr,"OK\n");
  if(naxes[0]!=nj){
    fprintf(stderr,"\nDifferent image size!\n");
    exit(0);
  }

  for(k=0;k<200;k++){
    zsum[k]=0;ssum[k]=0;
    for(i=k*9;i<(k+1)*9;i++){
      for(j=300;j<naxes[0]-300;j++){
	zsum[k]+=z[i][j];
	ssum[k]+=s[i][j];
      }
    }
  }
  zs=0;z2s=0;
  for(k=0;k<200;k++){
    zs+=zsum[k];
    z2s+=zsum[k]*zsum[k];
  }
  zav=zs/200;
  zsg=sqrt(z2s/200-zav*zav);
  nrej=1;
  while(nrej>0){
    nrej=0;zs=0;z2s=0;
    for(k=0;k<200;k++){
      if(zsum[k]>zav+zsg*3){
	zsum[k]=zav;
	nrej++;
	//fprintf(stderr,"Object #%d is rejected\n",k);
      }
      zs+=zsum[k];
      z2s+=zsum[k]*zsum[k];
    }
    zav=zs/200;zsg=sqrt(z2s/200-zav*zav);
  }
  for(k=0;k<200;k++){
    if(zsum[k]<zav-zsg*lev){
      for(i=k*9;i<(k+1)*9;i++){
	for(j=0;j<naxes[0];j++) z[i][j]=s[i][j];
      }
      fprintf(stderr,"Object #%d is filled\n",k);
    }
  }

  fprintf(stderr,"Write %s  ... ",argv[3]);
  status=0;
  if (fits_create_file(&fp, argv[3], &status))
    printerror(status);
  if (fits_create_img(fp, bitpix, naxis, naxes, &status))
    printerror(status);
  fpixel=1;
  nelements=naxes[0];
  for(i=0;i<naxes[1];i++){
    if (fits_write_img(fp, TFLOAT, fpixel, nelements, z[i], &status))
      printerror(status);
    fpixel+=naxes[0];
  }
  if (fits_close_file(fp, &status))
    printerror(status);
  fprintf(stderr,"OK\n");
  return(0);
}

void printerror( int status)
{
    /*****************************************************/
    /* Print out cfitsio error messages and exit program */
    /*****************************************************/

    char status_str[FLEN_STATUS], errmsg[FLEN_ERRMSG];

    if (status)
      fprintf(stderr, "\n*** Error occurred during program execution ***\n");

    fits_get_errstatus(status, status_str);   /* get the error description */
    fprintf(stderr, "\nstatus = %d: %s\n", status, status_str);

    /* get first message; null if stack is empty */
    if ( fits_read_errmsg(errmsg) )
    {
         fprintf(stderr, "\nError message stack:\n");
         fprintf(stderr, " %s\n", errmsg);

         while ( fits_read_errmsg(errmsg) )  /* get remaining messages */
             fprintf(stderr, " %s\n", errmsg);
    }

    exit( status );       /* terminate the program, returning error status */
}