Mercurial > octave-nkf
view scripts/audio/wavread.m @ 14868:5d3a684236b0
maint: Use Octave coding conventions for cuddling parentheses in scripts directory
* lin2mu.m, loadaudio.m, wavread.m, accumarray.m, bicubic.m, celldisp.m,
colon.m, cplxpair.m, dblquad.m, divergence.m, genvarname.m, gradient.m,
int2str.m, interp1.m, interp1q.m, interp2.m, interpn.m, loadobj.m, nthargout.m,
__isequal__.m, __splinen__.m, quadgk.m, quadl.m, quadv.m, rat.m, rot90.m,
rotdim.m, saveobj.m, subsindex.m, triplequad.m, delaunay3.m, griddata.m,
inpolygon.m, tsearchn.m, voronoi.m, get_first_help_sentence.m, which.m,
gray2ind.m, pink.m, dlmwrite.m, strread.m, textread.m, textscan.m, housh.m,
ishermitian.m, issymmetric.m, krylov.m, logm.m, null.m, rref.m,
compare_versions.m, copyfile.m, dump_prefs.m, edit.m, fileparts.m,
getappdata.m, isappdata.m, movefile.m, orderfields.m, parseparams.m,
__xzip__.m, rmappdata.m, setappdata.m, swapbytes.m, unpack.m, ver.m, fminbnd.m,
fminunc.m, fsolve.m, glpk.m, lsqnonneg.m, qp.m, sqp.m, configure_make.m,
copy_files.m, describe.m, get_description.m, get_forge_pkg.m, install.m,
installed_packages.m, is_architecture_dependent.m, load_package_dirs.m,
print_package_description.m, rebuild.m, repackage.m, save_order.m, shell.m,
allchild.m, ancestor.m, area.m, axes.m, axis.m, clabel.m, close.m, colorbar.m,
comet.m, comet3.m, contour.m, cylinder.m, ezmesh.m, ezsurf.m, findobj.m,
fplot.m, hist.m, isocolors.m, isonormals.m, isosurface.m, isprop.m, legend.m,
mesh.m, meshz.m, pareto.m, pcolor.m, peaks.m, plot3.m, plotmatrix.m, plotyy.m,
polar.m, print.m, __add_datasource__.m, __add_default_menu__.m,
__axes_limits__.m, __bar__.m, __clabel__.m, __contour__.m, __errcomm__.m,
__errplot__.m, __ezplot__.m, __file_filter__.m, __fltk_print__.m,
__ghostscript__.m, __gnuplot_print__.m, __go_draw_axes__.m,
__go_draw_figure__.m, __interp_cube__.m, __marching_cube__.m, __patch__.m,
__pie__.m, __plt__.m, __print_parse_opts__.m, __quiver__.m, __scatter__.m,
__stem__.m, __tight_eps_bbox__.m, __uigetdir_fltk__.m, __uigetfile_fltk__.m,
__uiputfile_fltk__.m, quiver.m, quiver3.m, rectangle.m, refreshdata.m,
ribbon.m, scatter.m, semilogy.m, shading.m, slice.m, subplot.m, surface.m,
surfl.m, surfnorm.m, text.m, uigetfile.m, uiputfile.m, whitebg.m, deconv.m,
mkpp.m, pchip.m, polyaffine.m, polyder.m, polygcd.m, polyout.m, polyval.m,
ppint.m, ppjumps.m, ppval.m, residue.m, roots.m, spline.m, splinefit.m,
addpref.m, getpref.m, setpref.m, ismember.m, setxor.m, arch_fit.m, arch_rnd.m,
arch_test.m, autoreg_matrix.m, diffpara.m, fftconv.m, filter2.m, hanning.m,
hurst.m, periodogram.m, triangle_sw.m, sinc.m, spectral_xdf.m, spencer.m,
stft.m, synthesis.m, unwrap.m, yulewalker.m, bicgstab.m, gmres.m, pcg.m, pcr.m,
__sprand_impl__.m, speye.m, spfun.m, sprandn.m, spstats.m, svds.m,
treelayout.m, treeplot.m, bessel.m, factor.m, legendre.m, perms.m, primes.m,
magic.m, toeplitz.m, corr.m, cov.m, mean.m, median.m, mode.m, qqplot.m,
quantile.m, ranks.m, zscore.m, logistic_regression_likelihood.m,
bartlett_test.m, chisquare_test_homogeneity.m, chisquare_test_independence.m,
kolmogorov_smirnov_test.m, run_test.m, u_test.m, wilcoxon_test.m, z_test.m,
z_test_2.m, bin2dec.m, dec2base.m, mat2str.m, strcat.m, strchr.m, strjust.m,
strtok.m, substr.m, untabify.m, assert.m, demo.m, example.m, fail.m, speed.m,
test.m, now.m: Use Octave coding conventions for cuddling parentheses in
scripts directory.
author | Rik <octave@nomad.inbox5.com> |
---|---|
date | Tue, 17 Jul 2012 07:08:39 -0700 |
parents | f3d52523cde1 |
children | 203c78063bff |
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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} {@var{y} =} wavread (@var{filename}) ## Load the RIFF/WAVE sound file @var{filename}, and return the samples ## in vector @var{y}. If the file contains multichannel data, then ## @var{y} is a matrix with the channels represented as columns. ## ## @deftypefnx {Function File} {[@var{y}, @var{Fs}, @var{bps}] =} wavread (@var{filename}) ## Additionally return the sample rate (@var{fs}) in Hz and the number of bits ## per sample (@var{bps}). ## ## @deftypefnx {Function File} {[@dots{}] =} wavread (@var{filename}, @var{n}) ## Read only the first @var{n} samples from each channel. ## ## @deftypefnx {Function File} {[@dots{}] =} wavread (@var{filename}, @var{n1} @var{n2}) ## Read only samples @var{n1} through @var{n2} from each channel. ## ## @deftypefnx {Function File} {[@var{samples}, @var{channels}] =} wavread (@var{filename}, "size") ## Return the number of samples (@var{n}) and channels (@var{ch}) ## instead of the audio data. ## @seealso{wavwrite} ## @end deftypefn ## Author: Michael Zeising <michael@michaels-website.de> ## Created: 06 December 2005 function [y, samples_per_sec, bits_per_sample] = wavread (filename, param) FORMAT_PCM = 0x0001; # PCM (8/16/32 bit) FORMAT_IEEE_FLOAT = 0x0003; # IEEE float (32/64 bit) BYTEORDER = "ieee-le"; if (nargin < 1 || nargin > 2) print_usage (); endif if (! ischar (filename)) error ("wavread: FILENAME must be a character string"); endif fid = -1; unwind_protect [fid, msg] = fopen (filename, "rb"); if (fid < 0) error ("wavread: %s", msg); endif ## Get file size. fseek (fid, 0, "eof"); file_size = ftell (fid); fseek (fid, 0, "bof"); ## Find RIFF chunk. riff_size = find_chunk (fid, "RIFF", file_size); riff_pos = ftell (fid); if (riff_size == -1) error ("wavread: file contains no RIFF chunk"); endif riff_type = char (fread (fid, 4))'; if (! strcmp (riff_type, "WAVE")) error ("wavread: file contains no WAVE signature"); endif riff_pos = riff_pos + 4; riff_size = riff_size - 4; ## Find format chunk inside the RIFF chunk. fseek (fid, riff_pos, "bof"); fmt_size = find_chunk (fid, "fmt ", riff_size); fmt_pos = ftell (fid); if (fmt_size == -1) error ("wavread: file contains no format chunk"); endif ## Find data chunk inside the RIFF chunk. ## We don't assume that it comes after the format chunk. fseek (fid, riff_pos, "bof"); data_size = find_chunk (fid, "data", riff_size); data_pos = ftell (fid); if (data_size == -1) error ("wavread: file contains no data chunk"); endif ### Read format chunk. fseek (fid, fmt_pos, "bof"); ## Sample format code. format_tag = fread (fid, 1, "uint16", 0, BYTEORDER); if (format_tag != FORMAT_PCM && format_tag != FORMAT_IEEE_FLOAT) error ("wavread: sample format %#x is not supported", format_tag); endif ## Number of interleaved channels. channels = fread (fid, 1, "uint16", 0, BYTEORDER); ## Sample rate. samples_per_sec = fread (fid, 1, "uint32", 0, BYTEORDER); ## Bits per sample. fseek (fid, 6, "cof"); bits_per_sample = fread (fid, 1, "uint16", 0, BYTEORDER); ### Read data chunk. fseek (fid, data_pos, "bof"); ## Determine sample data type. if (format_tag == FORMAT_PCM) switch (bits_per_sample) case 8 format = "uint8"; case 16 format = "int16"; case 24 format = "uint8"; case 32 format = "int32"; otherwise error ("wavread: %d bits sample resolution is not supported with PCM", bits_per_sample); endswitch else switch (bits_per_sample) case 32 format = "float32"; case 64 format = "float64"; otherwise error ("wavread: %d bits sample resolution is not supported with IEEE float", bits_per_sample); endswitch endif ## Parse arguments. if (nargin == 1) length = idivide (8 * data_size, bits_per_sample); else nparams = numel (param); if (nparams == 1) ## Number of samples is given. length = param * channels; elseif (nparams == 2) ## Sample range is given. if (fseek (fid, (param(1)-1) * channels * (bits_per_sample/8), "cof") < 0) warning ("wavread: seeking failed"); endif length = (param(2)-param(1)+1) * channels; elseif (nparams == 4 && char (param) == "size") ## Size of the file is requested. tmp = idivide (8 * data_size, channels * bits_per_sample); y = [tmp, channels]; return; else error ("wavread: invalid PARAM argument"); endif endif ## Read samples and close file. if (bits_per_sample == 24) length *= 3; endif [yi, n] = fread (fid, length, format, 0, BYTEORDER); unwind_protect_cleanup if (fid >= 0) fclose (fid); endif end_unwind_protect ## Check data. if (mod (numel (yi), channels) != 0) error ("wavread: data in %s doesn't match the number of channels", filename); endif if (bits_per_sample == 24) yi = reshape (yi, 3, rows (yi) / 3)'; yi(yi(:,3) >= 128, 3) -= 256; yi = yi * [1; 256; 65536]; endif if (format_tag == FORMAT_PCM) ## Normalize samples. switch (bits_per_sample) case 8 yi = (yi - 128)/128; case 16 yi /= 32768; case 24 yi /= 8388608; case 32 yi /= 2147483648; endswitch endif ## Deinterleave. nr = numel (yi) / channels; y = reshape (yi, channels, nr)'; endfunction ## Given a chunk_id, scan through chunks from the current file position ## though at most size bytes. Return the size of the found chunk, with ## file position pointing to the start of the chunk data. Return -1 for ## size if chunk is not found. function chunk_size = find_chunk (fid, chunk_id, size) id = ""; offset = 8; chunk_size = 0; while (! strcmp (id, chunk_id) && (offset < size)) fseek (fid, chunk_size, "cof"); id = char (fread (fid, 4))'; chunk_size = fread (fid, 1, "uint32", 0, "ieee-le"); ## Chunk sizes must be word-aligned (2 byte) chunk_size += rem (chunk_size, 2); offset = offset + 8 + chunk_size; endwhile if (! strcmp (id, chunk_id)) chunk_size = -1; endif endfunction ## Mark file as tested. Tests for wavread/wavwrite pair are in wavwrite.m. %!assert (1)