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+## Copyright (C) 1995, 1996, 1997  Andreas Weingessel
+## 
+## This program is free software; you can redistribute it and/or modify
+## it under the terms of the GNU General Public License as published by
+## the Free Software Foundation; either version 2, or (at your option)
+## any later version.
+## 
+## This program is distributed in the hope that it will be useful, but
+## WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+## General Public License for more details. 
+## 
+## You should have received a copy of the GNU General Public License
+## along with this file.  If not, write to the Free Software Foundation,
+## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+## usage:  X = synthesis (Y, c)
+##
+## recovers a signal X from its short-time Fourier transform Y. c =
+## [win_size, increment, window_type].
+##
+## Y and c can be derived by [Y, c] = stft (X [, ...]).
+  
+## Author:  AW <Andreas.Weingessel@ci.tuwien.ac.at>
+## Description:  Recover a signal from its short-term Fourier transform
+
+function X = synthesis (Y, c)
+  
+  if (nargin != 2)
+    usage ("X = synthesis (Y, c)");
+  endif
+  
+  [nr nc] = size (c);
+  if (nr * nc != 3)
+    error ("synthesis:  c must contain exactly 3 elements");
+  endif
+  
+  ## not necessary, enables better reading
+  win = c(1);      
+  inc = c(2);
+  w_type = c(3);
+  
+  if (w_type == 1)
+    H = hanning (win);
+  elseif (w_type == 2)
+    H = hamming (win);
+  elseif (w_type == 3)
+    H = ones (win, 1);
+  else
+    error ("synthesis:  window_type must be 1, 2, or 3");
+  endif
+    
+  Z = real (ifft (Y));
+  st = fix ((win-inc) / 2);
+  Z = Z(st:st+inc-1, :);
+  H = H(st:st+inc-1);
+
+  nc = columns(Z);
+  for i = 1:nc
+    Z(:, i) = Z(:, i) ./ H;
+  endfor
+  
+  X = reshape(Z, inc * nc, 1);
+  
+endfunction