lib/fft2d.lib

   1 import ( "fft.lib" ) ;
   2 import ( "complex.lib" ) ;
   3
   4 GREY_MAX = 256;
   5
   6 //fft2d(x,y) = vectorize(x) : vectorize(y) <: picks(n) : real2complex(n) : fft(n) : stops(n/2), pcplx_moduls(n/2) : modules_vector(n/2);
   7 //fft2d(x,y) = vectorize(x) : vectorize(y) : fft(x) : fftc(y) : pcplx_moduls(y) : modules_vector(y);
   8 //fft2d(x,y) = vectorize(x) : fft(x) : fftc(y) : pcplx_moduls(y) : modules_vector(y);
   9
  10 matricize(x, y) = vectorize(y) : vectorize(x);
  11
  12 ffts(n, m) = par(i, n, (fft(m) : nconcat(m)));
  13
  14 fftcs(n, m) = par(i, n, (fftc(m) : nconcat(m)));
  15
  16 lines_fft(n, m) = _ <: picks(n) : ffts(n, m) : nconcat(n);
  17
  18 lines_fftc(n, m) = _ <: picks(n) : fftcs(n, m) : nconcat(n);
  19
  20 take_column(n, m) = par(i, n, [m]) : nconcat(n);
  21
  22 matrix_transpose(n, m) = _ <: picks(n) <: par(i, m, take_column(n, i)) : nconcat(m);
  23
  24 matrix_pcplx2modul(n, m) = _ <: picks(n) : par(i, n, ( _ <: picks(m) : pcplx_moduls(m) : nconcat(m))) : nconcat(n);
  25
  26 matrix_real2pcplx(n, m) = _ <: picks(n) : par(i, n, ( _ <: picks(m) : real2pcplx(m) : nconcat(m))) : nconcat(n);
  27
  28 //normalize(n) = _ , n : /;
  29 normalize(n, m) = _, (m : vectorize(n)) : /;
  30
  31 unnormalize(n) = par(i, n, ( _ , GREY_MAX : *));
  32
  33 norm_out(n, m) = _ <: picks(n) : par(i, n, ( _ <: picks(m) : unnormalize(m) : nconcat(m))) : nconcat(n) : serialize;
  34
  35 output(n, m) = serialize;
  36
  37 //fft2d(x, y) = matricize(x, y) : lines_fft(x, y) : matrix_transpose(x, y) : lines_fftc(y, x) : matrix_transpose(y, x)  : output(x, y);
  38 //fft2d(x, y) = normalize(GREY_MAX) : matricize(x, y) : lines_fft(x, y) : matrix_transpose(x, y) : lines_fftc(y, x) : matrix_transpose(y, x) : norm_out(x, y);
  39 //fft2d(x, y) = matricize(x, y) : matrix_real2pcplx(x, y) : matrix_pcplx2modul(x, y) : output(x, y);
  40 //fft2d(x, y) = matricize(x, y) : output(x, y);
  41 fft2d(x, y) = normalize(GREY_MAX) : matricize(x, y) : lines_fft(x, y) : matrix_transpose(x, y) : lines_fftc(y, x) : matrix_transpose(y, x) : norm_out(x, y);
  42
  43 new_fft2d(x, y) = normalize(y, GREY_MAX) : vectorize(x) : lines_fft(x, y) : matrix_transpose(x, y) : lines_fftc(y, x) : matrix_transpose(y, x) : norm_out(x, y);
  44
  45 //safer with x=y because tests and zero padding are still to implement
  46 //process = fft2d(32,32);
  47
  48 //process = new_fft2d(32,32);
  49
  50
  51