* mln/transform/fft.hh (mln::transform::fft<T, internal::fft_real>::fft): Properly initialize the plan of the inverse transform using fftw_plan_dft_c2r_2d. (mln::transform::fft<T, internal::fft_real>::transform_inv): Use the entire complex values (not just their real parts) to compute the inverse transform. (mln::transform::class fft<T, internal::fft_cplx>::fft): Call the proper function (fftw_plan_dft_2d) to create the plan of the inverse transform. Switch the input and the output so that the inverse transform uses the right images. --- milena/ChangeLog | 17 +++++++++++++++++ milena/mln/transform/fft.hh | 15 ++++++++------- 2 files changed, 25 insertions(+), 7 deletions(-) diff --git a/milena/ChangeLog b/milena/ChangeLog index 83a2c76..8bc21f5 100644 --- a/milena/ChangeLog +++ b/milena/ChangeLog @@ -1,3 +1,20 @@ +2012-10-09 Roland Levillain <roland@lrde.epita.fr> + + Fix the Fast Fourier Transform. + + * mln/transform/fft.hh + (mln::transform::fft<T, internal::fft_real>::fft): + Properly initialize the plan of the inverse transform using + fftw_plan_dft_c2r_2d. + (mln::transform::fft<T, internal::fft_real>::transform_inv): + Use the entire complex values (not just their real parts) to + compute the inverse transform. + (mln::transform::class fft<T, internal::fft_cplx>::fft): + Call the proper function (fftw_plan_dft_2d) to create the plan of + the inverse transform. + Switch the input and the output so that the inverse transform uses + the right images. + 2012-10-09 Alexandre Abraham <abraham@lrde.epita.fr> Import the FFTW-based Fast Fourier Transform. diff --git a/milena/mln/transform/fft.hh b/milena/mln/transform/fft.hh index 0dafa7b..cf0f1bb 100644 --- a/milena/mln/transform/fft.hh +++ b/milena/mln/transform/fft.hh @@ -1,4 +1,5 @@ -// Copyright (C) 2007, 2008, 2009 EPITA Research and Development Laboratory +// Copyright (C) 2007, 2008, 2009, 2012 EPITA Research and Development +// Laboratory // // This file is part of the Milena Library. This library is free // software; you can redistribute it and/or modify it under the terms @@ -418,8 +419,8 @@ namespace mln { this->p = fftw_plan_dft_r2c_2d (original_im.nrows(), original_im.ncols(), this->in, reinterpret_cast<fftw_complex*>(this->out), FFTW_ESTIMATE); - this->p_inv = fftw_plan_dft_r2c_2d (original_im.nrows(), original_im.ncols(), - this->in, reinterpret_cast<fftw_complex*>(this->out), FFTW_ESTIMATE); + this->p_inv = fftw_plan_dft_c2r_2d (original_im.nrows(), original_im.ncols(), + reinterpret_cast<fftw_complex*>(this->out), this->in, FFTW_ESTIMATE); this->trans_im = image2d< std::complex<T> >(original_im.domain()); } @@ -460,7 +461,7 @@ namespace mln { for (unsigned row = 0; row < this->trans_im.nrows(); ++row) for (unsigned col = 0; col <= this->trans_im.ncols() / 2; ++col) this->out[row * (this->trans_im.ncols() / 2 + 1) + col] = - opt::at(this->trans_im, row, col).real(); + opt::at(this->trans_im, row, col); fftw_execute(this->p_inv); @@ -620,9 +621,9 @@ namespace mln { this->p = fftw_plan_dft_2d(original_im.nrows(), original_im.ncols(), this->in, this->out, FFTW_FORWARD, FFTW_ESTIMATE); - this->p_inv = fftw2d_plan_dft_2d(original_im.nrows(), original_im.ncols(), - this->in, this->out, - FFTW_BACKWARD, FFTW_ESTIMATE); + this->p_inv = fftw_plan_dft_2d(original_im.nrows(), original_im.ncols(), + this->out, this->in, + FFTW_BACKWARD, FFTW_ESTIMATE); this->trans_im = image2d< std::complex<T> >(original_im.domain()); } -- 1.7.10.4