Mercurial > forge
diff main/audio/ausave.m @ 0:6b33357c7561 octave-forge
Initial revision
author | pkienzle |
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date | Wed, 10 Oct 2001 19:54:49 +0000 |
parents | |
children | 4cad27e73814 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/main/audio/ausave.m Wed Oct 10 19:54:49 2001 +0000 @@ -0,0 +1,228 @@ +## Copyright (C) 1999 Paul Kienzle +## +## 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 of the License, 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 program; if not, write to the Free Software +## Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + +## usage: ausave('filename.ext', x, fs, format) +## +## Writes an audio file with the appropriate header. The extension on +## the filename determines the layout of the header. Currently supports +## .wav and .au layouts. Data is a matrix of audio samples, one row +## time step, one column per channel. Fs defaults to 8000 Hz. Format +## is one of ulaw, alaw, char, short, long, float, double +function ausave(path, data, rate, sampleformat) + + if nargin < 2 || nargin>4 + usage("ausave('filename.ext', x [, fs, sampleformat])"); + end + if nargin < 3, rate = 8000; end + if nargin < 4, sampleformat = 'short'; end + + ext = rindex(path, '.'); + if (ext == 0) + usage("ausave('filename.ext', x [, fs, sampleformat])"); + end + ext = tolower(substr(path, ext+1, length(path)-ext)); + + [samples, channels] = size(data); + + ## Microsoft .wav format + if strcmp(ext,'wav') + + ## Header format obtained from sox/wav.c + ## April 15, 1992 + ## Copyright 1992 Rick Richardson + ## Copyright 1991 Lance Norskog And Sundry Contributors + ## This source code is freely redistributable and may be used for + ## any purpose. This copyright notice must be maintained. + ## Lance Norskog And Sundry Contributors are not responsible for + ## the consequences of using this software. + + if (strcmp(sampleformat,'uchar')) + formatid = 1; + samplesize = 1; + elseif (strcmp(sampleformat,'short')) + formatid = 1; + samplesize = 2; + elseif (strcmp(sampleformat, 'long')) + formatid = 1; + samplesize = 4; + elseif (strcmp(sampleformat, 'alaw')) + formatid = 6; + samplesize = 1; + elseif (strcmp(sampleformat, 'ulaw')) + formatid = 7; + samplesize = 1; + else + error("%s is invalid format for .wav file\n", sampleformat); + end + datasize = channels*samplesize*samples; + + [file, msg] = fopen(path, 'w'); + if (file == -1) + error("%s: %s", msg, path); + end + + ## write the magic header + arch = 'ieee-le'; + fwrite(file, toascii('RIFF'), 'char'); + fwrite(file, datasize+36, 'long', 0, arch); + fwrite(file, toascii('WAVE'), 'char'); + + ## write the "fmt " section + fwrite(file, toascii('fmt '), 'char'); + fwrite(file, 16, 'long', 0, arch); + fwrite(file, formatid, 'short', 0, arch); + fwrite(file, channels, 'short', 0, arch); + fwrite(file, rate, 'long', 0, arch); + fwrite(file, rate*channels*samplesize, 'long', 0, arch); + fwrite(file, channels*samplesize, 'short', 0, arch); + fwrite(file, samplesize*8, 'short', 0, arch); + + ## write the "data" section + fwrite(file, toascii('data'), 'char'); + fwrite(file, datasize, 'long', 0, arch); + + ## Sun .au format + elseif strcmp(ext, 'au') + + ## Header format obtained from sox/au.c + ## September 25, 1991 + ## Copyright 1991 Guido van Rossum And Sundry Contributors + ## This source code is freely redistributable and may be used for + ## any purpose. This copyright notice must be maintained. + ## Guido van Rossum And Sundry Contributors are not responsible for + ## the consequences of using this software. + + if (strcmp(sampleformat, 'ulaw')) + formatid = 1; + samplesize = 1; + elseif (strcmp(sampleformat,'uchar')) + formatid = 2; + samplesize = 1; + elseif (strcmp(sampleformat,'short')) + formatid = 3; + samplesize = 2; + elseif (strcmp(sampleformat, 'long')) + formatid = 5; + samplesize = 4; + elseif (strcmp(sampleformat, 'float')) + formatid = 6; + samplesize = 4; + elseif (strcmp(sampleformat, 'double')) + formatid = 7; + samplesize = 8; + else + error("%s is invalid format for .au file\n", sampleformat); + end + datasize = channels*samplesize*samples; + + [file, msg] = fopen(path, 'w'); + if (file == -1) + error("%s: %s", msg, path); + end + + arch = 'ieee-be'; + fwrite(file, toascii('.snd'), 'char'); + fwrite(file, 24, 'long', 0, arch); + fwrite(file, datasize, 'long', 0, arch); + fwrite(file, formatid, 'long', 0, arch); + fwrite(file, rate, 'long', 0, arch); + fwrite(file, channels, 'long', 0, arch); + + ## Apple/SGI .aiff format + elseif strcmp(ext,'aiff') + + ## Header format obtained from sox/aiff.c + ## September 25, 1991 + ## Copyright 1991 Guido van Rossum And Sundry Contributors + ## This source code is freely redistributable and may be used for + ## any purpose. This copyright notice must be maintained. + ## Guido van Rossum And Sundry Contributors are not responsible for + ## the consequences of using this software. + ## + ## IEEE 80-bit float I/O taken from + ## ftp://ftp.mathworks.com/pub/contrib/signal/osprey.tar + ## David K. Mellinger + ## dave@mbari.org + ## +1-831-775-1805 + ## fax -1620 + ## Monterey Bay Aquarium Research Institute + ## 7700 Sandholdt Road + + if (strcmp(sampleformat,'uchar')) + samplesize = 1; + elseif (strcmp(sampleformat,'short')) + samplesize = 2; + elseif (strcmp(sampleformat, 'long')) + samplesize = 4; + else + error("%s is invalid format for .aiff file\n", sampleformat); + end + datasize = channels*samplesize*samples; + + [file, msg] = fopen(path, 'w'); + if (file == -1) + error("%s: %s", msg, path); + end + + ## write the magic header + arch = 'ieee-be'; + fwrite(file, toascii('FORM'), 'char'); + fwrite(file, datasize+46, 'long', 0, arch); + fwrite(file, toascii('AIFF'), 'char'); + + ## write the "COMM" section + fwrite(file, toascii('COMM'), 'char'); + fwrite(file, 18, 'long', 0, arch); + fwrite(file, channels, 'short', 0, arch); + fwrite(file, samples, 'long', 0, arch); + fwrite(file, 8*samplesize, 'short', 0, arch); + fwrite(file, 16414, 'ushort', 0, arch); % sample rate exponent + fwrite(file, [rate, 0], 'ulong', 0, arch); % sample rate mantissa + + ## write the "SSND" section + fwrite(file, toascii('SSND'), 'char'); + fwrite(file, datasize+8, 'long', 0, arch); # section length + fwrite(file, 0, 'long', 0, arch); # block size + fwrite(file, 0, 'long', 0, arch); # offset + + ## file extension unknown + else + error('ausave(filename.ext,...) understands .wav .au and .aiff only'); + end + + ## convert samples from range [-1, 1) + if strcmp(sampleformat, 'alaw') + error("FIXME: ausave needs linear to alaw conversion\n"); + precision = 'uchar'; + elseif strcmp(sampleformat, 'ulaw') + data = lin2mu(data); + precision = 'uchar' + elseif strcmp(sampleformat, 'uchar') + data = data*128 + 128; + precision = 'uchar'; + elseif strcmp(sampleformat, 'short') + data = data*32768; + precision = 'short'; + elseif strcmp(sampleformat, 'long') + data = data*2^31; + precision = 'long'; + else + precision = sampleformat; + end + fwrite(file, data', precision, 0, arch); + fclose(file); + +endfunction