wav.c revision 1.2
1 /* 2 * Copyright (c) 2002 Matthew R. Green 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. The name of the author may not be used to endorse or promote products 14 * derived from this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 22 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 /* 30 * WAV support for the audio tools; thanks go to the sox utility for 31 * clearing up issues with WAV files. 32 */ 33 34 #include <sys/types.h> 35 #include <sys/audioio.h> 36 #include <sys/ioctl.h> 37 #include <sys/time.h> 38 39 #include <ctype.h> 40 #include <err.h> 41 #include <stdio.h> 42 #include <stdlib.h> 43 #include <string.h> 44 45 #include "libaudio.h" 46 47 struct { 48 int wenc; 49 const char *wname; 50 } wavencs[] = { 51 { WAVE_FORMAT_UNKNOWN, "Microsoft Official Unknown" }, 52 { WAVE_FORMAT_PCM, "Microsoft PCM" }, 53 { WAVE_FORMAT_ADPCM, "Microsoft ADPCM" }, 54 { WAVE_FORMAT_ALAW, "Microsoft A-law" }, 55 { WAVE_FORMAT_MULAW, "Microsoft U-law" }, 56 { WAVE_FORMAT_OKI_ADPCM,"OKI ADPCM" }, 57 { WAVE_FORMAT_DIGISTD, "Digistd format" }, 58 { WAVE_FORMAT_DIGIFIX, "Digifix format" }, 59 { -1, "?Unknown?" }, 60 }; 61 62 const char * 63 wav_enc_from_val(int encoding) 64 { 65 int i; 66 67 for (i = 0; wavencs[i].wenc != -1; i++) 68 if (wavencs[i].wenc == encoding) 69 break; 70 return (wavencs[i].wname); 71 } 72 73 /* 74 * sample header is: 75 * 76 * RIFF\^@^C^@WAVEfmt ^P^@^@^@^A^@^B^@D<AC>^@^@^P<B1>^B^@^D^@^P^@data^@^@^C^@^@^@^@^@^@^@^@^@^@ 77 * 78 */ 79 /* 80 * WAV format helpers 81 */ 82 /* 83 * find a .wav header, etc. returns header length on success 84 */ 85 ssize_t 86 audio_wav_parse_hdr(hdr, sz, enc, prec, sample, channels, datasize) 87 void *hdr; 88 size_t sz; 89 int *enc; 90 int *prec; 91 int *sample; 92 int *channels; 93 size_t *datasize; 94 { 95 char *where = hdr, *owhere; 96 wav_audioheaderpart part; 97 wav_audioheaderfmt fmt; 98 char *end = (((char *)hdr) + sz); 99 int newenc, newprec; 100 static const char 101 strfmt[4] = "fmt ", 102 strRIFF[4] = "RIFF", 103 strWAVE[4] = "WAVE", 104 strdata[4] = "data"; 105 106 if (sz < 32) 107 return (AUDIO_ENOENT); 108 109 if (strncmp(where, strRIFF, sizeof strRIFF)) 110 return (AUDIO_ENOENT); 111 where += 8; 112 if (strncmp(where, strWAVE, sizeof strWAVE)) 113 return (AUDIO_ENOENT); 114 where += 4; 115 116 do { 117 memcpy(&part, where, sizeof part); 118 owhere = where; 119 where += getle32(part.len) + 8; 120 } while (where < end && strncmp(part.name, strfmt, sizeof strfmt)); 121 122 /* too short ? */ 123 if (where + sizeof fmt > end) 124 return (AUDIO_ESHORTHDR); 125 126 memcpy(&fmt, (owhere + 8), sizeof fmt); 127 128 #if 0 129 printf("fmt header is:\n\t%d\ttag\n\t%d\tchannels\n\t%d\tsample rate\n\t%d\tavg_bps\n\t%d\talignment\n\t%d\tbits per sample\n", getle16(fmt.tag), getle16(fmt.channels), getle32(fmt.sample_rate), getle32(fmt.avg_bps), getle16(fmt.alignment), getle16(fmt.bits_per_sample)); 130 #endif 131 132 switch (getle16(fmt.tag)) { 133 case WAVE_FORMAT_UNKNOWN: 134 case WAVE_FORMAT_ADPCM: 135 case WAVE_FORMAT_OKI_ADPCM: 136 case WAVE_FORMAT_DIGISTD: 137 case WAVE_FORMAT_DIGIFIX: 138 case IBM_FORMAT_MULAW: 139 case IBM_FORMAT_ALAW: 140 case IBM_FORMAT_ADPCM: 141 default: 142 return (AUDIO_EWAVUNSUPP); 143 144 case WAVE_FORMAT_PCM: 145 switch (getle16(fmt.bits_per_sample)) { 146 case 8: 147 newprec = 8; 148 break; 149 case 16: 150 newprec = 16; 151 break; 152 case 24: 153 newprec = 24; 154 break; 155 case 32: 156 newprec = 32; 157 break; 158 default: 159 return (AUDIO_EWAVBADPCM); 160 } 161 if (newprec == 8) 162 newenc = AUDIO_ENCODING_ULINEAR_LE; 163 else 164 newenc = AUDIO_ENCODING_SLINEAR_LE; 165 break; 166 case WAVE_FORMAT_ALAW: 167 newenc = AUDIO_ENCODING_ALAW; 168 newprec = 8; 169 break; 170 case WAVE_FORMAT_MULAW: 171 newenc = AUDIO_ENCODING_ULAW; 172 newprec = 8; 173 break; 174 } 175 176 do { 177 memcpy(&part, where, sizeof part); 178 #if 0 179 printf("part `%c%c%c%c' len = %d\n", part.name[0], part.name[1], part.name[2], part.name[3], getle32(part.len)); 180 #endif 181 owhere = where; 182 where += (getle32(part.len) + 8); 183 } while (where < end && strncmp(part.name, strdata, sizeof strdata)); 184 185 if ((where - getle32(part.len)) <= end) { 186 if (channels) 187 *channels = getle16(fmt.channels); 188 if (sample) 189 *sample = getle32(fmt.sample_rate); 190 if (enc) 191 *enc = newenc; 192 if (prec) 193 *prec = newprec; 194 if (datasize) 195 *datasize = (size_t)getle32(part.len); 196 return (owhere - (char *)hdr + 8); 197 } 198 return (AUDIO_EWAVNODATA); 199 } 200
Indexes created Fri Sep 26 20:09:58 GMT 2025