<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/xhtml;charset=UTF-8"/>
<title>SphinxBase: src/libsphinxad/ad_alsa.c Source File</title>
<link href="tabs.css" rel="stylesheet" type="text/css"/>
<link href="navtree.css" rel="stylesheet" type="text/css"/>
<script type="text/javascript" src="jquery.js"></script>
<script type="text/javascript" src="navtree.js"></script>
<script type="text/javascript" src="resize.js"></script>
<script type="text/javascript">
$(document).ready(initResizable);
</script>
<link href="doxygen.css" rel="stylesheet" type="text/css"/>
</head>
<body>
<!-- Generated by Doxygen 1.7.3 -->
<div id="top">
<div id="titlearea">
<table cellspacing="0" cellpadding="0">
<tbody>
<tr style="height: 56px;">
<td style="padding-left: 0.5em;">
<div id="projectname">SphinxBase <span id="projectnumber">0.6</span></div>
</td>
</tr>
</tbody>
</table>
</div>
<div id="navrow1" class="tabs">
<ul class="tablist">
<li><a href="index.html"><span>Main Page</span></a></li>
<li><a href="pages.html"><span>Related Pages</span></a></li>
<li><a href="annotated.html"><span>Data Structures</span></a></li>
<li class="current"><a href="files.html"><span>Files</span></a></li>
</ul>
</div>
<div id="navrow2" class="tabs2">
<ul class="tablist">
<li><a href="files.html"><span>File List</span></a></li>
<li><a href="globals.html"><span>Globals</span></a></li>
</ul>
</div>
</div>
<div id="side-nav" class="ui-resizable side-nav-resizable">
<div id="nav-tree">
<div id="nav-tree-contents">
</div>
</div>
<div id="splitbar" style="-moz-user-select:none;"
class="ui-resizable-handle">
</div>
</div>
<script type="text/javascript">
initNavTree('ad__alsa_8c.html','');
</script>
<div id="doc-content">
<div class="header">
<div class="headertitle">
<h1>src/libsphinxad/ad_alsa.c</h1> </div>
</div>
<div class="contents">
<div class="fragment"><pre class="fragment"><a name="l00001"></a>00001 <span class="comment">/* -*- c-basic-offset: 4; indent-tabs-mode: nil -*- */</span>
<a name="l00002"></a>00002 <span class="comment">/* ====================================================================</span>
<a name="l00003"></a>00003 <span class="comment"> * Copyright (c) 1999-2001 Carnegie Mellon University. All rights</span>
<a name="l00004"></a>00004 <span class="comment"> * reserved.</span>
<a name="l00005"></a>00005 <span class="comment"> *</span>
<a name="l00006"></a>00006 <span class="comment"> * Redistribution and use in source and binary forms, with or without</span>
<a name="l00007"></a>00007 <span class="comment"> * modification, are permitted provided that the following conditions</span>
<a name="l00008"></a>00008 <span class="comment"> * are met:</span>
<a name="l00009"></a>00009 <span class="comment"> *</span>
<a name="l00010"></a>00010 <span class="comment"> * 1. Redistributions of source code must retain the above copyright</span>
<a name="l00011"></a>00011 <span class="comment"> * notice, this list of conditions and the following disclaimer. </span>
<a name="l00012"></a>00012 <span class="comment"> *</span>
<a name="l00013"></a>00013 <span class="comment"> * 2. Redistributions in binary form must reproduce the above copyright</span>
<a name="l00014"></a>00014 <span class="comment"> * notice, this list of conditions and the following disclaimer in</span>
<a name="l00015"></a>00015 <span class="comment"> * the documentation and/or other materials provided with the</span>
<a name="l00016"></a>00016 <span class="comment"> * distribution.</span>
<a name="l00017"></a>00017 <span class="comment"> *</span>
<a name="l00018"></a>00018 <span class="comment"> * This work was supported in part by funding from the Defense Advanced </span>
<a name="l00019"></a>00019 <span class="comment"> * Research Projects Agency and the National Science Foundation of the </span>
<a name="l00020"></a>00020 <span class="comment"> * United States of America, and the CMU Sphinx Speech Consortium.</span>
<a name="l00021"></a>00021 <span class="comment"> *</span>
<a name="l00022"></a>00022 <span class="comment"> * THIS SOFTWARE IS PROVIDED BY CARNEGIE MELLON UNIVERSITY ``AS IS'' AND </span>
<a name="l00023"></a>00023 <span class="comment"> * ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, </span>
<a name="l00024"></a>00024 <span class="comment"> * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR</span>
<a name="l00025"></a>00025 <span class="comment"> * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY</span>
<a name="l00026"></a>00026 <span class="comment"> * NOR ITS EMPLOYEES BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,</span>
<a name="l00027"></a>00027 <span class="comment"> * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT </span>
<a name="l00028"></a>00028 <span class="comment"> * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, </span>
<a name="l00029"></a>00029 <span class="comment"> * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY </span>
<a name="l00030"></a>00030 <span class="comment"> * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT </span>
<a name="l00031"></a>00031 <span class="comment"> * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE </span>
<a name="l00032"></a>00032 <span class="comment"> * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.</span>
<a name="l00033"></a>00033 <span class="comment"> *</span>
<a name="l00034"></a>00034 <span class="comment"> * ====================================================================</span>
<a name="l00035"></a>00035 <span class="comment"> *</span>
<a name="l00036"></a>00036 <span class="comment"> */</span>
<a name="l00037"></a>00037 <span class="comment">/* -*- mode:c; indent-tabs-mode:t; c-basic-offset:4; comment-column:40 -*-</span>
<a name="l00038"></a>00038 <span class="comment"> *</span>
<a name="l00039"></a>00039 <span class="comment"> * Sphinx II libad (Linux)</span>
<a name="l00040"></a>00040 <span class="comment"> * ^^^^^^^^^^^^^^^^^^^^^^^</span>
<a name="l00041"></a>00041 <span class="comment"> * $Id: ad_alsa.c,v 1.6 2001/12/11 00:24:48 lenzo Exp $</span>
<a name="l00042"></a>00042 <span class="comment"> *</span>
<a name="l00043"></a>00043 <span class="comment"> * John G. Dorsey (jd5q+@andrew.cmu.edu)</span>
<a name="l00044"></a>00044 <span class="comment"> * Engineering Design Research Center</span>
<a name="l00045"></a>00045 <span class="comment"> * Carnegie Mellon University</span>
<a name="l00046"></a>00046 <span class="comment"> * ***************************************************************************</span>
<a name="l00047"></a>00047 <span class="comment"> * </span>
<a name="l00048"></a>00048 <span class="comment"> * REVISION HISTORY</span>
<a name="l00049"></a>00049 <span class="comment"> *</span>
<a name="l00050"></a>00050 <span class="comment"> * 18-Mar-2006 David Huggins-Daines <dhuggins@cs.cmu.edu></span>
<a name="l00051"></a>00051 <span class="comment"> * Update this to the ALSA 1.0 API.</span>
<a name="l00052"></a>00052 <span class="comment"> *</span>
<a name="l00053"></a>00053 <span class="comment"> * 12-Dec-2000 David Huggins-Daines <dhd@cepstral.com> at Cepstral LLC</span>
<a name="l00054"></a>00054 <span class="comment"> * Make this at least compile with the new ALSA API.</span>
<a name="l00055"></a>00055 <span class="comment"> *</span>
<a name="l00056"></a>00056 <span class="comment"> * 05-Nov-1999 Sean Levy (snl@stalphonsos.com) at St. Alphonsos, LLC.</span>
<a name="l00057"></a>00057 <span class="comment"> * Ported to ALSA so I can actually get working full-duplex.</span>
<a name="l00058"></a>00058 <span class="comment"> *</span>
<a name="l00059"></a>00059 <span class="comment"> * 09-Aug-1999 Kevin Lenzo (lenzo@cs.cmu.edu) at Cernegie Mellon University.</span>
<a name="l00060"></a>00060 <span class="comment"> * Incorporated nickr@cs.cmu.edu's changes (marked below) and</span>
<a name="l00061"></a>00061 <span class="comment"> * SPS_EPSILON to allow for sample rates that are "close enough".</span>
<a name="l00062"></a>00062 <span class="comment"> * </span>
<a name="l00063"></a>00063 <span class="comment"> * 15-Jun-1999 M. K. Ravishankar (rkm@cs.cmu.edu) at Carnegie Mellon Univ.</span>
<a name="l00064"></a>00064 <span class="comment"> * Consolidated all ad functions into</span>
<a name="l00065"></a>00065 <span class="comment"> * this one file. Added ad_open_sps().</span>
<a name="l00066"></a>00066 <span class="comment"> * Other cosmetic changes for consistency (e.g., use of err.h).</span>
<a name="l00067"></a>00067 <span class="comment"> * </span>
<a name="l00068"></a>00068 <span class="comment"> * 18-May-1999 Kevin Lenzo (lenzo@cs.cmu.edu) added <errno.h>.</span>
<a name="l00069"></a>00069 <span class="comment"> */</span>
<a name="l00070"></a>00070
<a name="l00071"></a>00071
<a name="l00072"></a>00072 <span class="preprocessor">#include <fcntl.h></span>
<a name="l00073"></a>00073 <span class="preprocessor">#include <stdio.h></span>
<a name="l00074"></a>00074 <span class="preprocessor">#include <stdlib.h></span>
<a name="l00075"></a>00075 <span class="preprocessor">#include <string.h></span>
<a name="l00076"></a>00076 <span class="preprocessor">#include <alsa/asoundlib.h></span>
<a name="l00077"></a>00077 <span class="preprocessor">#include <errno.h></span>
<a name="l00078"></a>00078 <span class="preprocessor">#include <config.h></span>
<a name="l00079"></a>00079 <span class="preprocessor">#include <unistd.h></span>
<a name="l00080"></a>00080
<a name="l00081"></a>00081 <span class="preprocessor">#include "prim_type.h"</span>
<a name="l00082"></a>00082 <span class="preprocessor">#include "ad.h"</span>
<a name="l00083"></a>00083
<a name="l00084"></a>00084
<a name="l00085"></a>00085 <span class="preprocessor">#define AUDIO_FORMAT SND_PCM_SFMT_S16_LE </span><span class="comment">/* 16-bit signed, little endian */</span>
<a name="l00086"></a>00086 <span class="preprocessor">#define INPUT_GAIN (85)</span>
<a name="l00087"></a>00087 <span class="preprocessor"></span><span class="preprocessor">#define SPS_EPSILON 200</span>
<a name="l00088"></a>00088 <span class="preprocessor"></span>
<a name="l00089"></a>00089 <span class="keyword">static</span> <span class="keywordtype">int</span>
<a name="l00090"></a>00090 setparams(int32 sps, snd_pcm_t * handle)
<a name="l00091"></a>00091 {
<a name="l00092"></a>00092 snd_pcm_hw_params_t *hwparams;
<a name="l00093"></a>00093 <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> out_sps, buffer_time, period_time;
<a name="l00094"></a>00094 <span class="keywordtype">int</span> err;
<a name="l00095"></a>00095
<a name="l00096"></a>00096 snd_pcm_hw_params_alloca(&hwparams);
<a name="l00097"></a>00097 err = snd_pcm_hw_params_any(handle, hwparams);
<a name="l00098"></a>00098 <span class="keywordflow">if</span> (err < 0) {
<a name="l00099"></a>00099 fprintf(stderr, <span class="stringliteral">"Can not configure this PCM device: %s\n"</span>,
<a name="l00100"></a>00100 snd_strerror(err));
<a name="l00101"></a>00101 <span class="keywordflow">return</span> -1;
<a name="l00102"></a>00102 }
<a name="l00103"></a>00103
<a name="l00104"></a>00104 err =
<a name="l00105"></a>00105 snd_pcm_hw_params_set_access(handle, hwparams,
<a name="l00106"></a>00106 SND_PCM_ACCESS_RW_INTERLEAVED);
<a name="l00107"></a>00107 <span class="keywordflow">if</span> (err < 0) {
<a name="l00108"></a>00108 fprintf(stderr,
<a name="l00109"></a>00109 <span class="stringliteral">"Failed to set PCM device to interleaved: %s\n"</span>,
<a name="l00110"></a>00110 snd_strerror(err));
<a name="l00111"></a>00111 <span class="keywordflow">return</span> -1;
<a name="l00112"></a>00112 }
<a name="l00113"></a>00113
<a name="l00114"></a>00114 err =
<a name="l00115"></a>00115 snd_pcm_hw_params_set_format(handle, hwparams, SND_PCM_FORMAT_S16);
<a name="l00116"></a>00116 <span class="keywordflow">if</span> (err < 0) {
<a name="l00117"></a>00117 fprintf(stderr,
<a name="l00118"></a>00118 <span class="stringliteral">"Failed to set PCM device to 16-bit signed PCM: %s\n"</span>,
<a name="l00119"></a>00119 snd_strerror(err));
<a name="l00120"></a>00120 <span class="keywordflow">return</span> -1;
<a name="l00121"></a>00121 }
<a name="l00122"></a>00122
<a name="l00123"></a>00123 err = snd_pcm_hw_params_set_channels(handle, hwparams, 1);
<a name="l00124"></a>00124 <span class="keywordflow">if</span> (err < 0) {
<a name="l00125"></a>00125 fprintf(stderr, <span class="stringliteral">"Failed to set PCM device to mono: %s\n"</span>,
<a name="l00126"></a>00126 snd_strerror(err));
<a name="l00127"></a>00127 <span class="keywordflow">return</span> -1;
<a name="l00128"></a>00128 }
<a name="l00129"></a>00129
<a name="l00130"></a>00130 out_sps = sps;
<a name="l00131"></a>00131 err =
<a name="l00132"></a>00132 snd_pcm_hw_params_set_rate_near(handle, hwparams, &out_sps, NULL);
<a name="l00133"></a>00133 <span class="keywordflow">if</span> (err < 0) {
<a name="l00134"></a>00134 fprintf(stderr, <span class="stringliteral">"Failed to set sampling rate: %s\n"</span>,
<a name="l00135"></a>00135 snd_strerror(err));
<a name="l00136"></a>00136 <span class="keywordflow">return</span> -1;
<a name="l00137"></a>00137 }
<a name="l00138"></a>00138 <span class="keywordflow">if</span> (abs(out_sps - sps) > SPS_EPSILON) {
<a name="l00139"></a>00139 fprintf(stderr,
<a name="l00140"></a>00140 <span class="stringliteral">"Available samping rate %d is too far from requested %d\n"</span>,
<a name="l00141"></a>00141 out_sps, sps);
<a name="l00142"></a>00142 <span class="keywordflow">return</span> -1;
<a name="l00143"></a>00143 }
<a name="l00144"></a>00144
<a name="l00145"></a>00145 <span class="comment">/* Set buffer time to the maximum. */</span>
<a name="l00146"></a>00146 err = snd_pcm_hw_params_get_buffer_time_max(hwparams, &buffer_time, 0);
<a name="l00147"></a>00147 period_time = buffer_time / 4;
<a name="l00148"></a>00148 err = snd_pcm_hw_params_set_period_time_near(handle, hwparams,
<a name="l00149"></a>00149 &period_time, 0);
<a name="l00150"></a>00150 <span class="keywordflow">if</span> (err < 0) {
<a name="l00151"></a>00151 fprintf(stderr, <span class="stringliteral">"Failed to set period time to %u: %s\n"</span>,
<a name="l00152"></a>00152 period_time, snd_strerror(err));
<a name="l00153"></a>00153 <span class="keywordflow">return</span> -1;
<a name="l00154"></a>00154 }
<a name="l00155"></a>00155 err = snd_pcm_hw_params_set_buffer_time_near(handle, hwparams,
<a name="l00156"></a>00156 &buffer_time, 0);
<a name="l00157"></a>00157 <span class="keywordflow">if</span> (err < 0) {
<a name="l00158"></a>00158 fprintf(stderr, <span class="stringliteral">"Failed to set buffer time to %u: %s\n"</span>,
<a name="l00159"></a>00159 buffer_time, snd_strerror(err));
<a name="l00160"></a>00160 <span class="keywordflow">return</span> -1;
<a name="l00161"></a>00161 }
<a name="l00162"></a>00162
<a name="l00163"></a>00163 err = snd_pcm_hw_params(handle, hwparams);
<a name="l00164"></a>00164 <span class="keywordflow">if</span> (err < 0) {
<a name="l00165"></a>00165 fprintf(stderr, <span class="stringliteral">"Failed to set hwparams: %s\n"</span>, snd_strerror(err));
<a name="l00166"></a>00166 <span class="keywordflow">return</span> -1;
<a name="l00167"></a>00167 }
<a name="l00168"></a>00168
<a name="l00169"></a>00169 err = snd_pcm_nonblock(handle, 1);
<a name="l00170"></a>00170 <span class="keywordflow">if</span> (err < 0) {
<a name="l00171"></a>00171 fprintf(stderr, <span class="stringliteral">"Failed to set non-blocking mode: %s\n"</span>,
<a name="l00172"></a>00172 snd_strerror(err));
<a name="l00173"></a>00173 <span class="keywordflow">return</span> -1;
<a name="l00174"></a>00174 }
<a name="l00175"></a>00175 <span class="keywordflow">return</span> 0;
<a name="l00176"></a>00176 }
<a name="l00177"></a>00177
<a name="l00178"></a>00178 <span class="keyword">static</span> <span class="keywordtype">int</span>
<a name="l00179"></a>00179 setlevels(<span class="keyword">const</span> <span class="keywordtype">char</span> *dev)
<a name="l00180"></a>00180 {
<a name="l00181"></a>00181 snd_mixer_t *handle;
<a name="l00182"></a>00182 snd_mixer_selem_id_t *sid;
<a name="l00183"></a>00183 snd_mixer_elem_t *elem;
<a name="l00184"></a>00184 <span class="keywordtype">int</span> err;
<a name="l00185"></a>00185 <span class="keywordtype">char</span> *mixer_dev, *c;
<a name="l00186"></a>00186
<a name="l00187"></a>00187 <span class="comment">/* Basically we just want to turn on Mic capture. */</span>
<a name="l00188"></a>00188 <span class="keywordflow">if</span> ((err = snd_mixer_open(&handle, 0)) < 0) {
<a name="l00189"></a>00189 fprintf(stderr, <span class="stringliteral">"Mixer open failed: %s\n"</span>, snd_strerror(err));
<a name="l00190"></a>00190 <span class="keywordflow">return</span> -1;
<a name="l00191"></a>00191 }
<a name="l00192"></a>00192
<a name="l00193"></a>00193 mixer_dev = strdup(dev);
<a name="l00194"></a>00194 <span class="keywordflow">if</span> (strncmp(mixer_dev, <span class="stringliteral">"plug"</span>, 4) == 0)
<a name="l00195"></a>00195 memmove(mixer_dev, mixer_dev + 4, strlen(mixer_dev) - 4 + 1);
<a name="l00196"></a>00196 <span class="keywordflow">if</span> ((c = strchr(mixer_dev, <span class="charliteral">','</span>)))
<a name="l00197"></a>00197 *c = <span class="charliteral">'\0'</span>;
<a name="l00198"></a>00198 <span class="keywordflow">if</span> ((err = snd_mixer_attach(handle, mixer_dev)) < 0) {
<a name="l00199"></a>00199 fprintf(stderr, <span class="stringliteral">"Mixer attach to %s failed: %s\n"</span>,
<a name="l00200"></a>00200 mixer_dev, snd_strerror(err));
<a name="l00201"></a>00201 free(mixer_dev);
<a name="l00202"></a>00202 snd_mixer_close(handle);
<a name="l00203"></a>00203 <span class="keywordflow">return</span> -1;
<a name="l00204"></a>00204 }
<a name="l00205"></a>00205 free(mixer_dev);
<a name="l00206"></a>00206 <span class="keywordflow">if</span> ((err = snd_mixer_selem_register(handle, NULL, NULL)) < 0) {
<a name="l00207"></a>00207 fprintf(stderr, <span class="stringliteral">"Mixer register failed: %s\n"</span>, snd_strerror(err));
<a name="l00208"></a>00208 snd_mixer_close(handle);
<a name="l00209"></a>00209 <span class="keywordflow">return</span> -1;
<a name="l00210"></a>00210 }
<a name="l00211"></a>00211 <span class="keywordflow">if</span> ((err = snd_mixer_load(handle)) < 0) {
<a name="l00212"></a>00212 fprintf(stderr, <span class="stringliteral">"Mixer load failed: %s\n"</span>, snd_strerror(err));
<a name="l00213"></a>00213 snd_mixer_close(handle);
<a name="l00214"></a>00214 <span class="keywordflow">return</span> -1;
<a name="l00215"></a>00215 }
<a name="l00216"></a>00216 snd_mixer_selem_id_alloca(&sid);
<a name="l00217"></a>00217 snd_mixer_selem_id_set_name(sid, <span class="stringliteral">"Mic"</span>);
<a name="l00218"></a>00218 <span class="keywordflow">if</span> ((elem = snd_mixer_find_selem(handle, sid)) == NULL) {
<a name="l00219"></a>00219 fprintf(stderr, <span class="stringliteral">"Warning: Could not find Mic element\n"</span>);
<a name="l00220"></a>00220 }
<a name="l00221"></a>00221 <span class="keywordflow">else</span> {
<a name="l00222"></a>00222 <span class="keywordflow">if</span> (snd_mixer_selem_has_capture_switch(elem)) {
<a name="l00223"></a>00223 <span class="keywordflow">if</span> ((err = snd_mixer_selem_set_capture_switch_all(elem, 1)) < 0) {
<a name="l00224"></a>00224 fprintf(stderr,
<a name="l00225"></a>00225 <span class="stringliteral">"Failed to enable microphone capture: %s\n"</span>,
<a name="l00226"></a>00226 snd_strerror(err));
<a name="l00227"></a>00227 snd_mixer_close(handle);
<a name="l00228"></a>00228 <span class="keywordflow">return</span> -1;
<a name="l00229"></a>00229 }
<a name="l00230"></a>00230 }
<a name="l00231"></a>00231 }
<a name="l00232"></a>00232 snd_mixer_selem_id_set_name(sid, <span class="stringliteral">"Capture"</span>);
<a name="l00233"></a>00233 <span class="keywordflow">if</span> ((elem = snd_mixer_find_selem(handle, sid)) == NULL) {
<a name="l00234"></a>00234 fprintf(stderr, <span class="stringliteral">"Warning: Could not find Capture element\n"</span>);
<a name="l00235"></a>00235 }
<a name="l00236"></a>00236 <span class="keywordflow">else</span> {
<a name="l00237"></a>00237 <span class="keywordflow">if</span> (snd_mixer_selem_has_capture_switch(elem)) {
<a name="l00238"></a>00238 <span class="keywordflow">if</span> ((err = snd_mixer_selem_set_capture_switch_all(elem, 1)) < 0) {
<a name="l00239"></a>00239 fprintf(stderr,
<a name="l00240"></a>00240 <span class="stringliteral">"Failed to enable microphone capture: %s\n"</span>,
<a name="l00241"></a>00241 snd_strerror(err));
<a name="l00242"></a>00242 snd_mixer_close(handle);
<a name="l00243"></a>00243 <span class="keywordflow">return</span> -1;
<a name="l00244"></a>00244 }
<a name="l00245"></a>00245 }
<a name="l00246"></a>00246 }
<a name="l00247"></a>00247
<a name="l00248"></a>00248 <span class="keywordflow">return</span> 0;
<a name="l00249"></a>00249 }
<a name="l00250"></a>00250
<a name="l00251"></a>00251 <a class="code" href="structad__rec__t.html">ad_rec_t</a> *
<a name="l00252"></a><a class="code" href="ad_8h.html#a43f66257a2457d6c711dc5c694bfc02f">00252</a> <a class="code" href="ad_8h.html#a43f66257a2457d6c711dc5c694bfc02f" title="Open a specific audio device for recording.">ad_open_dev</a>(<span class="keyword">const</span> <span class="keywordtype">char</span> *dev, int32 sps)
<a name="l00253"></a>00253 {
<a name="l00254"></a>00254 <a class="code" href="structad__rec__t.html">ad_rec_t</a> *handle;
<a name="l00255"></a>00255 snd_pcm_t *dspH;
<a name="l00256"></a>00256
<a name="l00257"></a>00257 <span class="keywordtype">int</span> err;
<a name="l00258"></a>00258
<a name="l00259"></a>00259 <span class="keywordflow">if</span> (dev == NULL)
<a name="l00260"></a>00260 dev = DEFAULT_DEVICE;
<a name="l00261"></a>00261
<a name="l00262"></a>00262 err = snd_pcm_open(&dspH, dev, SND_PCM_STREAM_CAPTURE, 0);
<a name="l00263"></a>00263 <span class="keywordflow">if</span> (err < 0) {
<a name="l00264"></a>00264 fprintf(stderr,
<a name="l00265"></a>00265 <span class="stringliteral">"Error opening audio device %s for capture: %s\n"</span>,
<a name="l00266"></a>00266 dev, snd_strerror(err));
<a name="l00267"></a>00267 <span class="keywordflow">return</span> NULL;
<a name="l00268"></a>00268 }
<a name="l00269"></a>00269
<a name="l00270"></a>00270 <span class="keywordflow">if</span> (setparams(sps, dspH) < 0) {
<a name="l00271"></a>00271 <span class="keywordflow">return</span> NULL;
<a name="l00272"></a>00272 }
<a name="l00273"></a>00273 <span class="keywordflow">if</span> (setlevels(dev) < 0) {
<a name="l00274"></a>00274 <span class="keywordflow">return</span> NULL;
<a name="l00275"></a>00275 }
<a name="l00276"></a>00276 <span class="keywordflow">if</span> ((handle = (<a class="code" href="structad__rec__t.html">ad_rec_t</a> *) calloc(1, <span class="keyword">sizeof</span>(<a class="code" href="structad__rec__t.html">ad_rec_t</a>))) == NULL) {
<a name="l00277"></a>00277 fprintf(stderr, <span class="stringliteral">"calloc(%d) failed\n"</span>, (<span class="keywordtype">int</span>)<span class="keyword">sizeof</span>(<a class="code" href="structad__rec__t.html">ad_rec_t</a>));
<a name="l00278"></a>00278 abort();
<a name="l00279"></a>00279 }
<a name="l00280"></a>00280
<a name="l00281"></a>00281 handle->dspH = dspH;
<a name="l00282"></a>00282 handle->recording = 0;
<a name="l00283"></a>00283 handle-><a class="code" href="structad__rec__t.html#ac8ccccdc755f68cb4ad24007b36d6c8a" title="Samples/sec.">sps</a> = sps;
<a name="l00284"></a>00284 handle-><a class="code" href="structad__rec__t.html#ade5a608978908d87deea7fa9827f8510" title="Bytes/sample.">bps</a> = <span class="keyword">sizeof</span>(int16);
<a name="l00285"></a>00285
<a name="l00286"></a>00286 <span class="keywordflow">return</span> (handle);
<a name="l00287"></a>00287 }
<a name="l00288"></a>00288
<a name="l00289"></a>00289 <a class="code" href="structad__rec__t.html">ad_rec_t</a> *
<a name="l00290"></a><a class="code" href="ad_8h.html#a71b4eec805fbe5c398ea0897816de6f0">00290</a> <a class="code" href="ad_8h.html#a71b4eec805fbe5c398ea0897816de6f0" title="Open the default audio device with a given sampling rate.">ad_open_sps</a>(int32 sps)
<a name="l00291"></a>00291 {
<a name="l00292"></a>00292 <span class="keywordflow">return</span> <a class="code" href="ad_8h.html#a43f66257a2457d6c711dc5c694bfc02f" title="Open a specific audio device for recording.">ad_open_dev</a>(DEFAULT_DEVICE, sps);
<a name="l00293"></a>00293 }
<a name="l00294"></a>00294
<a name="l00295"></a>00295 <a class="code" href="structad__rec__t.html">ad_rec_t</a> *
<a name="l00296"></a><a class="code" href="ad_8h.html#a3def0da951e840fb4c72ef9259540686">00296</a> <a class="code" href="ad_8h.html#a3def0da951e840fb4c72ef9259540686" title="Open the default audio device.">ad_open</a>(<span class="keywordtype">void</span>)
<a name="l00297"></a>00297 {
<a name="l00298"></a>00298 <span class="keywordflow">return</span> <a class="code" href="ad_8h.html#a71b4eec805fbe5c398ea0897816de6f0" title="Open the default audio device with a given sampling rate.">ad_open_sps</a>(DEFAULT_SAMPLES_PER_SEC);
<a name="l00299"></a>00299 }
<a name="l00300"></a>00300
<a name="l00301"></a>00301
<a name="l00302"></a>00302 int32
<a name="l00303"></a>00303 ad_close(<a class="code" href="structad__rec__t.html">ad_rec_t</a> * handle)
<a name="l00304"></a>00304 {
<a name="l00305"></a>00305 <span class="keywordflow">if</span> (handle->dspH == NULL)
<a name="l00306"></a>00306 <span class="keywordflow">return</span> AD_ERR_NOT_OPEN;
<a name="l00307"></a>00307
<a name="l00308"></a>00308 <span class="keywordflow">if</span> (handle->recording) {
<a name="l00309"></a>00309 <span class="keywordflow">if</span> (ad_stop_rec(handle) < 0)
<a name="l00310"></a>00310 <span class="keywordflow">return</span> AD_ERR_GEN;
<a name="l00311"></a>00311 }
<a name="l00312"></a>00312 snd_pcm_close(handle->dspH);
<a name="l00313"></a>00313 free(handle);
<a name="l00314"></a>00314
<a name="l00315"></a>00315 <span class="keywordflow">return</span> (0);
<a name="l00316"></a>00316 }
<a name="l00317"></a>00317
<a name="l00318"></a>00318
<a name="l00319"></a>00319 int32
<a name="l00320"></a>00320 ad_start_rec(<a class="code" href="structad__rec__t.html">ad_rec_t</a> * handle)
<a name="l00321"></a>00321 {
<a name="l00322"></a>00322 <span class="keywordtype">int</span> err;
<a name="l00323"></a>00323
<a name="l00324"></a>00324 <span class="keywordflow">if</span> (handle->dspH == NULL)
<a name="l00325"></a>00325 <span class="keywordflow">return</span> AD_ERR_NOT_OPEN;
<a name="l00326"></a>00326
<a name="l00327"></a>00327 <span class="keywordflow">if</span> (handle->recording)
<a name="l00328"></a>00328 <span class="keywordflow">return</span> AD_ERR_GEN;
<a name="l00329"></a>00329
<a name="l00330"></a>00330 err = snd_pcm_prepare(handle->dspH);
<a name="l00331"></a>00331 <span class="keywordflow">if</span> (err < 0) {
<a name="l00332"></a>00332 fprintf(stderr, <span class="stringliteral">"snd_pcm_prepare failed: %s\n"</span>, snd_strerror(err));
<a name="l00333"></a>00333 <span class="keywordflow">return</span> AD_ERR_GEN;
<a name="l00334"></a>00334 }
<a name="l00335"></a>00335 err = snd_pcm_start(handle->dspH);
<a name="l00336"></a>00336 <span class="keywordflow">if</span> (err < 0) {
<a name="l00337"></a>00337 fprintf(stderr, <span class="stringliteral">"snd_pcm_start failed: %s\n"</span>, snd_strerror(err));
<a name="l00338"></a>00338 <span class="keywordflow">return</span> AD_ERR_GEN;
<a name="l00339"></a>00339 }
<a name="l00340"></a>00340 handle->recording = 1;
<a name="l00341"></a>00341
<a name="l00342"></a>00342 <span class="keywordflow">return</span> (0);
<a name="l00343"></a>00343 }
<a name="l00344"></a>00344
<a name="l00345"></a>00345
<a name="l00346"></a>00346 int32
<a name="l00347"></a>00347 ad_stop_rec(<a class="code" href="structad__rec__t.html">ad_rec_t</a> * handle)
<a name="l00348"></a>00348 {
<a name="l00349"></a>00349 <span class="keywordtype">int</span> err;
<a name="l00350"></a>00350
<a name="l00351"></a>00351 <span class="keywordflow">if</span> (handle->dspH == NULL)
<a name="l00352"></a>00352 <span class="keywordflow">return</span> AD_ERR_NOT_OPEN;
<a name="l00353"></a>00353
<a name="l00354"></a>00354 <span class="keywordflow">if</span> (!handle->recording)
<a name="l00355"></a>00355 <span class="keywordflow">return</span> AD_ERR_GEN;
<a name="l00356"></a>00356
<a name="l00357"></a>00357 err = snd_pcm_drop(handle->dspH);
<a name="l00358"></a>00358 <span class="keywordflow">if</span> (err < 0) {
<a name="l00359"></a>00359 fprintf(stderr, <span class="stringliteral">"snd_pcm_drop failed: %s\n"</span>, snd_strerror(err));
<a name="l00360"></a>00360 <span class="keywordflow">return</span> AD_ERR_GEN;
<a name="l00361"></a>00361 }
<a name="l00362"></a>00362 handle->recording = 0;
<a name="l00363"></a>00363
<a name="l00364"></a>00364 <span class="keywordflow">return</span> (0);
<a name="l00365"></a>00365 }
<a name="l00366"></a>00366
<a name="l00367"></a>00367
<a name="l00368"></a>00368 int32
<a name="l00369"></a>00369 ad_read(<a class="code" href="structad__rec__t.html">ad_rec_t</a> * handle, int16 * buf, int32 max)
<a name="l00370"></a>00370 {
<a name="l00371"></a>00371 int32 length, err;
<a name="l00372"></a>00372
<a name="l00373"></a>00373 <span class="keywordflow">if</span> (!handle->recording)
<a name="l00374"></a>00374 <span class="keywordflow">return</span> AD_EOF;
<a name="l00375"></a>00375
<a name="l00376"></a>00376 length = snd_pcm_readi(handle->dspH, buf, max);
<a name="l00377"></a>00377 <span class="keywordflow">if</span> (length == -EAGAIN) {
<a name="l00378"></a>00378 length = 0;
<a name="l00379"></a>00379 }
<a name="l00380"></a>00380 <span class="keywordflow">else</span> <span class="keywordflow">if</span> (length == -EPIPE) {
<a name="l00381"></a>00381 fprintf(stderr, <span class="stringliteral">"Input overrun, read calls are too rare (non-fatal)\n"</span>);
<a name="l00382"></a>00382 err = snd_pcm_prepare(handle->dspH);
<a name="l00383"></a>00383 <span class="keywordflow">if</span> (err < 0) {
<a name="l00384"></a>00384 fprintf(stderr, <span class="stringliteral">"Can't recover from underrun: %s\n"</span>,
<a name="l00385"></a>00385 snd_strerror(err));
<a name="l00386"></a>00386 <span class="keywordflow">return</span> AD_ERR_GEN;
<a name="l00387"></a>00387 }
<a name="l00388"></a>00388 length = 0;
<a name="l00389"></a>00389 }
<a name="l00390"></a>00390 <span class="keywordflow">else</span> <span class="keywordflow">if</span> (length == -ESTRPIPE) {
<a name="l00391"></a>00391 fprintf(stderr, <span class="stringliteral">"Resuming sound driver (non-fatal)\n"</span>);
<a name="l00392"></a>00392 <span class="keywordflow">while</span> ((err = snd_pcm_resume(handle->dspH)) == -EAGAIN)
<a name="l00393"></a>00393 usleep(10000); <span class="comment">/* Wait for the driver to wake up */</span>
<a name="l00394"></a>00394 <span class="keywordflow">if</span> (err < 0) {
<a name="l00395"></a>00395 err = snd_pcm_prepare(handle->dspH);
<a name="l00396"></a>00396 <span class="keywordflow">if</span> (err < 0) {
<a name="l00397"></a>00397 fprintf(stderr, <span class="stringliteral">"Can't recover from underrun: %s\n"</span>,
<a name="l00398"></a>00398 snd_strerror(err));
<a name="l00399"></a>00399 <span class="keywordflow">return</span> AD_ERR_GEN;
<a name="l00400"></a>00400 }
<a name="l00401"></a>00401 }
<a name="l00402"></a>00402 length = 0;
<a name="l00403"></a>00403 }
<a name="l00404"></a>00404 <span class="keywordflow">else</span> <span class="keywordflow">if</span> (length < 0) {
<a name="l00405"></a>00405 fprintf(stderr, <span class="stringliteral">"Audio read error: %s\n"</span>,
<a name="l00406"></a>00406 snd_strerror(length));
<a name="l00407"></a>00407 <span class="keywordflow">return</span> AD_ERR_GEN;
<a name="l00408"></a>00408 }
<a name="l00409"></a>00409 <span class="keywordflow">return</span> length;
<a name="l00410"></a>00410 }
</pre></div></div>
</div>
<div id="nav-path" class="navpath">
<ul>
<li class="navelem"><b>ad_alsa.c</b> </li>
<li class="footer">Generated on Tue Apr 19 2011 for SphinxBase by 
<a href="http://www.doxygen.org/index.html">
<img class="footer" src="doxygen.png" alt="doxygen"/></a> 1.7.3 </li>
</ul>
</div>
</body>
</html>
distrib
>
Fedora
>
14
>
x86_64
>
media
>
updates
>
by-pkgid
>
0b420d0fce195cf4115dc6a3be5c2da2
>
files
>
51
