xref: /netbsd/usr.bin/audio/common/wav.c (revision c4a72b64)
1 /*	$NetBSD: wav.c,v 1.4 2002/12/08 10:49:03 mrg Exp $	*/
2 
3 /*
4  * Copyright (c) 2002 Matthew R. Green
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. The name of the author may not be used to endorse or promote products
16  *    derived from this software without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
23  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
24  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
25  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
26  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 /*
32  * WAV support for the audio tools; thanks go to the sox utility for
33  * clearing up issues with WAV files.
34  */
35 
36 #include <sys/types.h>
37 #include <sys/audioio.h>
38 #include <sys/ioctl.h>
39 #include <sys/time.h>
40 
41 #include <ctype.h>
42 #include <err.h>
43 #include <stdio.h>
44 #include <stdlib.h>
45 #include <string.h>
46 
47 #include "libaudio.h"
48 
49 struct {
50 	int	wenc;
51 	const char *wname;
52 } wavencs[] = {
53 	{ WAVE_FORMAT_UNKNOWN, 	"Microsoft Official Unknown" },
54 	{ WAVE_FORMAT_PCM,	"Microsoft PCM" },
55 	{ WAVE_FORMAT_ADPCM,	"Microsoft ADPCM" },
56 	{ WAVE_FORMAT_ALAW,	"Microsoft A-law" },
57 	{ WAVE_FORMAT_MULAW,	"Microsoft U-law" },
58 	{ WAVE_FORMAT_OKI_ADPCM,"OKI ADPCM" },
59 	{ WAVE_FORMAT_DIGISTD,	"Digistd format" },
60 	{ WAVE_FORMAT_DIGIFIX,	"Digifix format" },
61 	{ -1, 			"?Unknown?" },
62 };
63 
64 const char *
65 wav_enc_from_val(int encoding)
66 {
67 	int	i;
68 
69 	for (i = 0; wavencs[i].wenc != -1; i++)
70 		if (wavencs[i].wenc == encoding)
71 			break;
72 	return (wavencs[i].wname);
73 }
74 
75 /*
76  * sample header is:
77  *
78  *   RIFF\^@^C^@WAVEfmt ^P^@^@^@^A^@^B^@D<AC>^@^@^P<B1>^B^@^D^@^P^@data^@^@^C^@^@^@^@^@^@^@^@^@^@
79  *
80  */
81 /*
82  * WAV format helpers
83  */
84 /*
85  * find a .wav header, etc. returns header length on success
86  */
87 ssize_t
88 audio_wav_parse_hdr(hdr, sz, enc, prec, sample, channels, datasize)
89 	void	*hdr;
90 	size_t	sz;
91 	int	*enc;
92 	int	*prec;
93 	int	*sample;
94 	int	*channels;
95 	size_t *datasize;
96 {
97 	char	*where = hdr, *owhere;
98 	wav_audioheaderpart part;
99 	wav_audioheaderfmt fmt;
100 	char	*end = (((char *)hdr) + sz);
101 	int	newenc, newprec;
102 	static const char
103 	    strfmt[4] = "fmt ",
104 	    strRIFF[4] = "RIFF",
105 	    strWAVE[4] = "WAVE",
106 	    strdata[4] = "data";
107 
108 	if (sz < 32)
109 		return (AUDIO_ENOENT);
110 
111 	if (strncmp(where, strRIFF, sizeof strRIFF))
112 		return (AUDIO_ENOENT);
113 	where += 8;
114 	if (strncmp(where, strWAVE, sizeof strWAVE))
115 		return (AUDIO_ENOENT);
116 	where += 4;
117 
118 	do {
119 		memcpy(&part, where, sizeof part);
120 		owhere = where;
121 		where += getle32(part.len) + 8;
122 	} while (where < end && strncmp(part.name, strfmt, sizeof strfmt));
123 
124 	/* too short ? */
125 	if (where + sizeof fmt > end)
126 		return (AUDIO_ESHORTHDR);
127 
128 	memcpy(&fmt, (owhere + 8), sizeof fmt);
129 
130 	switch (getle16(fmt.tag)) {
131 	case WAVE_FORMAT_UNKNOWN:
132 	case WAVE_FORMAT_ADPCM:
133 	case WAVE_FORMAT_OKI_ADPCM:
134 	case WAVE_FORMAT_DIGISTD:
135 	case WAVE_FORMAT_DIGIFIX:
136 	case IBM_FORMAT_MULAW:
137 	case IBM_FORMAT_ALAW:
138 	case IBM_FORMAT_ADPCM:
139 	default:
140 		return (AUDIO_EWAVUNSUPP);
141 
142 	case WAVE_FORMAT_PCM:
143 		switch (getle16(fmt.bits_per_sample)) {
144 		case 8:
145 			newprec = 8;
146 			break;
147 		case 16:
148 			newprec = 16;
149 			break;
150 		case 24:
151 			newprec = 24;
152 			break;
153 		case 32:
154 			newprec = 32;
155 			break;
156 		default:
157 			return (AUDIO_EWAVBADPCM);
158 		}
159 		if (newprec == 8)
160 			newenc = AUDIO_ENCODING_ULINEAR_LE;
161 		else
162 			newenc = AUDIO_ENCODING_SLINEAR_LE;
163 		break;
164 	case WAVE_FORMAT_ALAW:
165 		newenc = AUDIO_ENCODING_ALAW;
166 		newprec = 8;
167 		break;
168 	case WAVE_FORMAT_MULAW:
169 		newenc = AUDIO_ENCODING_ULAW;
170 		newprec = 8;
171 		break;
172 	}
173 
174 	do {
175 		memcpy(&part, where, sizeof part);
176 		owhere = where;
177 		where += (getle32(part.len) + 8);
178 	} while (where < end && strncmp(part.name, strdata, sizeof strdata));
179 
180 	if ((where - getle32(part.len)) <= end) {
181 		if (channels)
182 			*channels = getle16(fmt.channels);
183 		if (sample)
184 			*sample = getle32(fmt.sample_rate);
185 		if (enc)
186 			*enc = newenc;
187 		if (prec)
188 			*prec = newprec;
189 		if (datasize)
190 			*datasize = (size_t)getle32(part.len);
191 		return (owhere - (char *)hdr + 8);
192 	}
193 	return (AUDIO_EWAVNODATA);
194 }
195