void
aan_mascara_imagen (float *red_input,
float *green_input,
float *blue_input,
float *red_output,
float *green_output,
float *blue_output,
int width,
int height,
float **m)
{
aan_mascara_canal (red_input, red_output, width, height, m);
aan_mascara_canal (green_input, green_output, width, height, m);
aan_mascara_canal (blue_input, blue_output, width, height, m);
}
void calcular_gradiente(float *canal_input,float *canal_output,int width,int height){
float masc_horizontal[3][3]= {{-(2.-sqrt(2.))/4.,0.,(2.-sqrt(2.))/4.},{-2.*(sqrt(2.)-1.)/4,0.,2.*(sqrt(2.)-1.)/4.},{-(2.-sqrt(2.))/4.,0.,(2.-sqrt(2.))/4.}};
float masc_vertical[3][3] = {{-(2.-sqrt(2.))/4.,-2.*(sqrt(2.)-1.)/4.,-(2.-sqrt(2.))/4.},{0.,0.,0.},{(2.-sqrt(2.))/4.,2.*(sqrt(2.)-1.)/4.,(2.-sqrt(2.))/4.}};
float *h,*v;
int i;
h = (float*)malloc((width*height)*sizeof(float));
v = (float*)malloc((width*height)*sizeof(float));
aan_mascara_canal(canal_input,h,width,height,masc_horizontal);
aan_mascara_canal(canal_input,v,width,height,masc_vertical);
for(i=0;i<(height*width);i++){
canal_output[i]= sqrt((h[i]*h[i])+(v[i]*v[i]));
};
free(h);
free(v);
}
/* Utilizamos una mascara laplaciana como aproximacion al modulo del gradiente */
float*
grad_horizontal (float *input, int width, int height)
{
float *grad;
float **u_x;
grad = (float*)malloc (sizeof(float) * width * height);
ami_malloc2d (u_x, float, 3, 3);
u_x[0][0] = 0.25 * -(2.0 - sqrt(2.0)); u_x[0][1] = 0; u_x[0][2] = 0.25 * (2.0 - sqrt(2.0));
u_x[1][0] = 0.25 * -2.0 * (sqrt(2.0) - 1); u_x[1][1] = 0; u_x[1][2] = 0.25 * 2.0 * (sqrt(2.0) - 1);
u_x[2][0] = 0.25 * -(2.0 - sqrt(2.0)); u_x[2][1] = 0; u_x[2][2] = 0.25 * (2.0 - sqrt(2.0));
/* u_x[0][0] = -3.0; u_x[0][1] = 0; u_x[0][2] = 3.0;
u_x[1][0] = -10.0; u_x[1][1] = 0; u_x[1][2] = 10.0;
u_x[2][0] = -3.0; u_x[2][1] = 0; u_x[2][2] = 3.0;*/
aan_mascara_canal (input, grad, width, height, u_x);
ami_free2d(u_x);
return grad;
}
int
main (int argc, char **argv)
{
int i, w, h;
unsigned char *red1, *green1, *blue1,
*red2, *green2, *blue2,
*red3, *green3, *blue3;
float *fred1, *fgreen1, *fblue1,
*fred2, *fgreen2, *fblue2;
float **u_x, **u_y, **lap;
if (argc < 2)
{
fprintf (stderr, "Usage: %s <BMP file>\n", argv[0]);
return -1;
}
/* Leemos el fichero dado por el primer argumento */
if (ami_read_bmp (argv[1], &red1, &green1, &blue1, &w, &h) < 0)
return -1;
ami_malloc2d (u_x, float, 3, 3);
ami_malloc2d (u_y, float, 3, 3);
ami_malloc2d (lap, float, 3, 3);
/* Gradiente horizontal */
u_x[0][0] = 0.25 * -(2.0 - sqrt(2.0)); u_x[0][1] = 0; u_x[0][2] = 0.25 * (2.0 - sqrt(2.0));
u_x[1][0] = 0.25 * -2.0 * (sqrt(2.0) - 1); u_x[1][1] = 0; u_x[1][2] = 0.25 * 2.0 * (sqrt(2.0) - 1);
u_x[2][0] = 0.25 * -(2.0 - sqrt(2.0)); u_x[2][1] = 0; u_x[2][2] = 0.25 * (2.0 - sqrt(2.0));
/* Gradiente vertical */
u_y[0][0] = 0.25 * -(2.0 - sqrt(2.0)); u_y[0][1] = 0.25 * -2.0 * (sqrt(2.0) - 1); u_y[0][2] = 0.25 * -(2.0-sqrt(2.0));
u_y[1][0] = 0; u_y[1][1] = 0; u_y[1][2] = 0;
u_y[2][0] = 0.25 * (2.0 - sqrt(2.0)); u_y[2][1] = 0.25 * 2.0 * (sqrt(2.0) - 1); u_y[2][2] = 0.25 * (2.0 - sqrt(2.0));
/* Pasamos los canales a precision flotante */
fred1 = uchar_to_float (red1, w * h);
fgreen1 = uchar_to_float (green1, w * h);
fblue1 = uchar_to_float (blue1, w * h);
aan_normalizar_imagen_float (fred1, fgreen1, fblue1, w , h);
fred2 = (float*) malloc (sizeof (float) * w * h);
fgreen2 = (float*) malloc (sizeof (float) * w * h);
fblue2 = (float*) malloc (sizeof (float) * w * h);
/* Usamos el gradiente horizontal en el canal verde */
aan_mascara_canal (fgreen1, fgreen2, w, h, u_x);
aan_mascara_canal (fred1, fred2, w, h, u_y);
for (i=0; i < (w * h) ;i++)
fblue2[i] = 127.0;
red2 = float_to_uchar (fred2, w * h);
green2 = float_to_uchar (fgreen2, w * h);
blue2 = float_to_uchar (fblue2, w * h);
aan_normalizar_imagen_float (fred2, fgreen2, fblue2, w , h);
aan_unir_canales_unsigned_char (red1, red2, &red3, w, h);
aan_unir_canales_unsigned_char (green1, green2, &green3, w, h);
aan_unir_canales_unsigned_char (blue1, blue2, &blue3, w, h);
ami_write_bmp ("./2_mascara_byn.bmp", red3, green3, blue3, w*2 + 4, h);
/* Liberamos memoria */
free (red2); free (green2); free (blue2);
free (red3); free (green3); free (blue3);
free (red1); free (green1); free (blue1);
free (fred1); free (fgreen1); free (fblue1);
free (fred2); free (fgreen2); free (fblue2);
ami_free2d (u_x); ami_free2d (u_y);
return 0;
}
