update packages

[CreaPhase.git] / octave_packages / m / audio / wavwrite.m

diff --git a/octave_packages/m/audio/wavwrite.m b/octave_packages/m/audio/wavwrite.m
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+## Copyright (C) 2005-2012 Michael Zeising
+##
+## This file is part of Octave.
+##
+## Octave 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 3 of the License, or (at
+## your option) any later version.
+##
+## Octave 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 Octave; see the file COPYING.  If not, see
+## <http://www.gnu.org/licenses/>.
+
+## -*- texinfo -*-
+## @deftypefn  {Function File} {} wavwrite (@var{y}, @var{filename})
+## @deftypefnx {Function File} {} wavwrite (@var{y}, @var{Fs}, @var{filename})
+## @deftypefnx {Function File} {} wavwrite (@var{y}, @var{Fs}, @var{bps}, @var{filename})
+## Write @var{y} to the canonical RIFF/WAVE sound file @var{filename}
+## with sample rate @var{Fs} and bits per sample @var{bps}.  The
+## default sample rate is 8000 Hz with 16-bits per sample.  Each column
+## of the data represents a separate channel.
+## @seealso{wavread}
+## @end deftypefn
+
+## Author: Michael Zeising <michael@michaels-website.de>
+## Created: 06 December 2005
+
+function wavwrite (y, varargin)
+
+  BYTEORDER = "ieee-le";
+
+  if (nargin < 2 || nargin > 4)
+    print_usage ();
+  endif
+
+  ## Defaults.
+  samples_per_sec = 8000;
+  bits_per_sample = 16;
+
+  filename = varargin{end};
+  if (nargin > 2)
+    samples_per_sec = varargin{1};
+    if (nargin > 3)
+      bits_per_sample = varargin{2};
+    endif
+  endif
+
+  ## test arguments
+  if (columns (y) < 1)
+    error ("wavwrite: Y must have at least one column");
+  endif
+  if (columns (y) > 0x7FFF)
+    error ("wavwrite: Y has more than 32767 columns (too many for a WAV-file)");
+  endif
+
+  ## determine sample format
+  switch (bits_per_sample)
+    case 8
+      format = "uint8";
+    case 16
+      format = "int16";
+    case 32
+      format = "int32";
+    otherwise
+      error ("wavwrite: sample resolution not supported");
+  endswitch
+
+  ## calculate filesize
+  [n, channels] = size (y);
+
+  ## size of data chunk
+  ck_size = n*channels*(bits_per_sample/8);
+
+  if (! ischar (filename))
+    error ("wavwrite: expecting FILENAME to be a character string");
+  endif
+
+  ## open file for writing binary
+  [fid, msg] = fopen (filename, "wb");
+  if (fid < 0)
+    error ("wavwrite: %s", msg);
+  endif
+
+  ## write RIFF/WAVE header
+  c = 0;
+  c += fwrite (fid, "RIFF", "uchar");
+
+  ## file size - 8
+  c += fwrite (fid, ck_size + 36, "uint32", 0, BYTEORDER);
+  c += fwrite (fid, "WAVEfmt ", "uchar");
+
+  ## size of fmt chunk
+  c += fwrite (fid, 16, "uint32", 0, BYTEORDER);
+
+  ## sample format code (PCM)
+  c += fwrite (fid, 1, "uint16", 0, BYTEORDER);
+
+  ## channels
+  c += fwrite (fid, channels, "uint16", 0, BYTEORDER);
+
+  ## sample rate
+  c += fwrite (fid, samples_per_sec, "uint32", 0, BYTEORDER);
+
+  ## bytes per second
+  byteps = samples_per_sec*channels*bits_per_sample/8;
+  c += fwrite (fid, byteps, "uint32", 0, BYTEORDER);
+
+  ## block align
+  c += fwrite (fid, channels*bits_per_sample/8, "uint16", 0, BYTEORDER);
+
+  c += fwrite (fid, bits_per_sample, "uint16", 0, BYTEORDER);
+  c += fwrite (fid, "data", "uchar");
+  c += fwrite (fid, ck_size, "uint32", 0, BYTEORDER);
+
+  if (c < 25)
+    fclose (fid);
+    error ("wavwrite: writing to file failed");
+  endif
+
+  ## interleave samples
+  yi = reshape (y', n*channels, 1);
+
+  ## scale samples
+  switch (bits_per_sample)
+    case 8
+      yi = round (yi*128 + 128);
+    case 16
+      yi = round (yi*32768);
+    case 32
+      yi = round (yi*2147483648);
+  endswitch
+
+  ## write to file
+  c = fwrite (fid, yi, format, 0, BYTEORDER);
+
+  fclose (fid);
+
+endfunction
+
+
+%!shared fname
+%! fname = tmpnam ();
+
+%!test
+%! A = [-1:0.1:1; -1:0.1:1];
+%! wavwrite (A, fname);
+%! [B, samples_per_sec, bits_per_sample] = wavread (fname);
+%! assert (A,B, 1/2^15);
+%! assert (samples_per_sec, 8000);
+%! assert (bits_per_sample, 16);
+%! unlink (fname);
+%
+%!test
+%! A = [-1:0.1:1; -1:0.1:1];
+%! wavwrite (A, 4000, fname);
+%! [B, samples_per_sec, bits_per_sample] = wavread (fname);
+%! assert (A,B, 1/2^15);
+%! assert (samples_per_sec, 4000);
+%! assert (bits_per_sample, 16);
+%! unlink (fname);
+%
+%!test
+%! A = [-1:0.1:1; -1:0.1:1];
+%! wavwrite (A, 4000, 8, fname);
+%! [B, samples_per_sec, bits_per_sample] = wavread (fname);
+%! assert (A,B, 1/128);
+%! assert (samples_per_sec, 4000);
+%! assert (bits_per_sample, 8);
+%! unlink (fname);
+%
+%!test
+%! A = [-2:2];
+%! wavwrite (A, fname);
+%! B = wavread (fname);
+%! B *= 32768;
+%! assert (B, [-32768 -32768 0 32767 32767]);
+%! unlink (fname);
+