[Vxl-users] fft_2d

[Wouter R. <wou...@fr...>]

Hi,=20

Question 1
    typedef vcl_complex<double> Complx;
    vil_image img =3D vil_load(filename);
    vil_memory_image_of<Complx> buf(img);
    int r=3Dbuf.rows();
    int c=3Dbuf.cols();
    vnl_matrix<Complx> A(buf,r,c);
    vnl_fft_2d<double> fft2d(r,c);              <-- assertion failure

ERROR:
    ../vnl_fft_prime_factors.txx:25 assertion failure
    '! "you probably gave a signal size not of the form 2^p 3^q 5^r=20
   =20
   My image is a .png (158x158) grayscale chessboard image.

Question 2
   Where can I find more example code (other than the VXL book)?
  =20
Thank you
wouter

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