filter.c

数字信号处理实验

void freq_filtering(double *re, double *im,
		    int w, int h)
{

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  int i,j,ms,mat_size, sx, sy ,ex, ey;
  double *retmp, *imtmp;

//  swap_quadrants(re, im, w, h);

  ms = w * h;

  printf("Input matrix size of n x n. n must be smaller than %d. n ? ",w);
  scanf("%d",&mat_size);
  mat_size = mat_size / 2;

  sx = w / 2 - mat_size;  ex = w / 2 + mat_size;
  sy = h / 2 - mat_size;  ey = h / 2 + mat_size;

  printf("%d, %d, %d, %d, %d, %d, %d\n", w, h, mat_size,sx, sy, ex, ey);

  for(i=sy;i<ey;i++)
    {
      for(j=sx;j<ex;j++)
	{
	  re[i * w + j] = 0.0;
	  im[i * w + j] = 0.0;
	}
    }
}