#define MAX
#include "lib.h"
#include <math.h>
#define Pi 3.14159

main (int argc, char *argv[])

{
int i, j, M, N ;
int conv, mi = 0, mj = 0, n, n1;
float sigma, expyg,normal,round,sum,r;
float masky[3][3];


IMAGE main_image=0;


if (argc < 2)
{
printf ("Usage: gaussiano <image>\n");
exit (1);
}

main_image = Input_PBM (argv[1]);
if (main_image == 0)
{
 printf ("No input image ('%s')\n", argv[1]);
 exit (2);
}

printf("Entre com sigma \n");
scanf("%f",&sigma);

//printf("Entre com o valor de n:  \n");
//scanf(" %d", &n) ;
//printf("Para esse valor de n, tem-se sigma = %f\n",sigma);

M = main_image->info->nr-1;
N = main_image->info->nc-1;

for(i=-1;i<=1;i++)
   {
   mj=0;
   for(j=-1;j<=1;j++)
      {
      //===========equação da função Gaussiana:=================
      r=(i*i)+(j*j);
      expyg=exp(-r/(2*sigma*sigma));
      //======Calcula o fator e normaliza o valor:========
      if(i==-1&&j==-1&&expyg!=0)        normal=fabs(1/expyg);    //fabs: valor absoluto
      r=(expyg*normal)/(sqrt(2*Pi))*sigma;
      



      //===============Arredonda o valor:=================
      //round=floor(r);



      if( ( (r-round)>0.5 ) || ( (r-round)<0 && (r-round)>-0.5 ) ) round++;


      //==============Escreve na máscara:=================
      masky[mi][mj]=r;

      sum=sum+round;

      mj++;
      }
      mi++;

   }


//====================Convolui a figura com a Máscara Gaussiana:==================


M = main_image->info->nr-3;
N = main_image->info->nc-3;

for(i=0;i<=M;i++)
   {
   printf("i %d \n",i);
   for(j=0;j<=N;j++)
      {
      conv=0;
      for(mi=0;mi<=2;mi++)
         {
         for(mj=0;mj<=2;mj++)
            {
            conv=conv+( masky[mi][mj]*main_image->data[i + mi][j + mj]); //multiplica e soma
            }
         }
         conv=conv/sum;                                     //normaliza o valor
         main_image->data[i + 1][j + 1] = conv;
      }
   }

Output_PBM (main_image, "FiltroGaussiano.pgm");
printf ("Arquivo de saída: 'FiltroGaussiano.pgm'\n");
}