void filtr(struct IMAGE * obr_pgm, int * fil, int size) {
    int **tab;
    size = size / sizeof(int);
    int suma, suma_wag = 0, i, j, k, m, rozm = (int)sqrt(size);
    int przesun = rozm / 2;
    tab = (int**)malloc(obr_pgm->width*sizeof(int*));
    for ( i = 0; i < obr_pgm->width; i++)
        tab[i] = (int*)malloc(obr_pgm->height*sizeof(int));

    for ( i = 0; i < obr_pgm->width; i++)
        {
            for ( j = 0; j < obr_pgm->height; j++)
            {
                tab[i][j] = obr_pgm->data[i][j];
            }
        }

    for (i = 0; i < size; i++)
    {
        suma_wag = suma_wag + fil[i];
    }

    for (i = przesun; i < ((obr_pgm->width) - przesun); i++) {
        for (j = przesun; j < ((obr_pgm->height) - przesun); j++) {
            suma = 0;
            for (k = 0; k < rozm; k++) {
                for (m = 0; m < rozm; m++) {
                    suma = suma + fil[k + m*rozm] * (tab[j + m - przesun][i + k - przesun]);
                }
            }
            if (suma_wag != 0)
                suma = suma / suma_wag;
            if (suma < 0)
                suma = 0;
            if (suma > obr_pgm->max)
                suma = obr_pgm->max;
            obr_pgm->data[j][i] = suma;
        }
    }
    for (i = 0; i < obr_pgm->width; i++)
        free(tab[i]);
    free(tab);
}