Mercurial > SDL_sound_CoreAudio
annotate decoders/voc.c @ 22:f6e679afe88b
Byte ordering fix, changed voc_read to voc_read_waveform, and cleaned up
some header includes.
| author | Ryan C. Gordon <icculus@icculus.org> |
|---|---|
| date | Wed, 19 Sep 2001 08:31:54 +0000 |
| parents | 41e5e07c5fed |
| children | 4a60ee42ca9a |
| rev | line source |
|---|---|
| 14 | 1 /* |
| 2 * SDL_sound -- An abstract sound format decoding API. | |
| 3 * Copyright (C) 2001 Ryan C. Gordon. | |
| 4 * | |
| 5 * This library is free software; you can redistribute it and/or | |
| 6 * modify it under the terms of the GNU Lesser General Public | |
| 7 * License as published by the Free Software Foundation; either | |
| 8 * version 2.1 of the License, or (at your option) any later version. | |
| 9 * | |
| 10 * This library is distributed in the hope that it will be useful, | |
| 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 13 * Lesser General Public License for more details. | |
| 14 * | |
| 15 * You should have received a copy of the GNU Lesser General Public | |
| 16 * License along with this library; if not, write to the Free Software | |
| 17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
| 18 */ | |
| 19 | |
| 20 /* | |
| 21 * VOC decoder for SDL_sound. | |
| 22 * | |
| 23 * This driver handles Creative Labs VOC audio data...this is a legacy format, | |
| 24 * but there's some game ports that could make use of such a decoder. Plus, | |
| 25 * VOC is fairly straightforward to decode, so this is a more complex, but | |
| 26 * still palatable example of an SDL_sound decoder. Y'know, in case the | |
| 27 * RAW decoder didn't do it for you. :) | |
| 28 * | |
| 29 * This code was ripped from a decoder I had written for SDL_mixer, which was | |
| 30 * largely ripped from sox v12.17.1's voc.c. | |
| 31 * | |
| 32 * SDL_mixer: http://www.libsdl.org/projects/SDL_mixer/ | |
| 33 * sox: http://www.freshmeat.net/projects/sox/ | |
| 34 * | |
| 35 * Please see the file LICENSE in the source's root directory. | |
| 36 * | |
| 37 * This file written by Ryan C. Gordon. (icculus@clutteredmind.org) | |
| 38 */ | |
| 39 | |
| 40 #include <stdio.h> | |
| 41 #include <stdlib.h> | |
| 42 #include <string.h> | |
| 43 #include <assert.h> | |
| 44 #include "SDL_sound.h" | |
| 45 | |
| 46 #define __SDL_SOUND_INTERNAL__ | |
| 47 #include "SDL_sound_internal.h" | |
| 48 | |
| 49 #if (!defined SOUND_SUPPORTS_VOC) | |
| 50 #error SOUND_SUPPORTS_VOC must be defined. | |
| 51 #endif | |
| 52 | |
| 53 | |
| 54 static int VOC_open(Sound_Sample *sample, const char *ext); | |
| 55 static void VOC_close(Sound_Sample *sample); | |
| 56 static Uint32 VOC_read(Sound_Sample *sample); | |
| 57 | |
| 58 const Sound_DecoderFunctions __Sound_DecoderFunctions_VOC = | |
| 59 { | |
| 60 { | |
| 61 "VOC", | |
| 62 "Creative Labs Voice format", | |
| 63 "Ryan C. Gordon <icculus@clutteredmind.org>", | |
| 64 "http://www.icculus.org/SDL_sound/" | |
| 65 }, | |
| 66 | |
| 67 VOC_open, /* open() method */ | |
| 68 VOC_close, /* close() method */ | |
| 69 VOC_read /* read() method */ | |
| 70 }; | |
| 71 | |
| 72 | |
| 73 /* Private data for VOC file */ | |
| 74 typedef struct vocstuff { | |
| 75 Uint32 rest; /* bytes remaining in current block */ | |
| 76 Uint32 rate; /* rate code (byte) of this chunk */ | |
| 77 int silent; /* sound or silence? */ | |
| 78 Uint32 srate; /* rate code (byte) of silence */ | |
| 79 Uint32 blockseek; /* start of current output block */ | |
| 80 Uint32 samples; /* number of samples output */ | |
| 81 Uint32 size; /* word length of data */ | |
| 82 int channels; /* number of sound channels */ | |
| 83 int extended; /* Has an extended block been read? */ | |
| 84 Uint32 bufpos; /* byte position in internal->buffer. */ | |
| 85 } vs_t; | |
| 86 | |
| 87 /* Size field */ | |
| 88 /* SJB: note that the 1st 3 are sometimes used as sizeof(type) */ | |
| 89 #define ST_SIZE_BYTE 1 | |
| 90 #define ST_SIZE_8BIT 1 | |
| 91 #define ST_SIZE_WORD 2 | |
| 92 #define ST_SIZE_16BIT 2 | |
| 93 #define ST_SIZE_DWORD 4 | |
| 94 #define ST_SIZE_32BIT 4 | |
| 95 #define ST_SIZE_FLOAT 5 | |
| 96 #define ST_SIZE_DOUBLE 6 | |
| 97 #define ST_SIZE_IEEE 7 /* IEEE 80-bit floats. */ | |
| 98 | |
| 99 /* Style field */ | |
| 100 #define ST_ENCODING_UNSIGNED 1 /* unsigned linear: Sound Blaster */ | |
| 101 #define ST_ENCODING_SIGN2 2 /* signed linear 2's comp: Mac */ | |
| 102 #define ST_ENCODING_ULAW 3 /* U-law signed logs: US telephony, SPARC */ | |
| 103 #define ST_ENCODING_ALAW 4 /* A-law signed logs: non-US telephony */ | |
| 104 #define ST_ENCODING_ADPCM 5 /* Compressed PCM */ | |
| 105 #define ST_ENCODING_IMA_ADPCM 6 /* Compressed PCM */ | |
| 106 #define ST_ENCODING_GSM 7 /* GSM 6.10 33-byte frame lossy compression */ | |
| 107 | |
| 108 #define VOC_TERM 0 | |
| 109 #define VOC_DATA 1 | |
| 110 #define VOC_CONT 2 | |
| 111 #define VOC_SILENCE 3 | |
| 112 #define VOC_MARKER 4 | |
| 113 #define VOC_TEXT 5 | |
| 114 #define VOC_LOOP 6 | |
| 115 #define VOC_LOOPEND 7 | |
| 116 #define VOC_EXTENDED 8 | |
| 117 #define VOC_DATA_16 9 | |
| 118 | |
| 119 | |
| 120 static __inline__ int voc_check_header(SDL_RWops *src) | |
| 121 { | |
| 122 /* VOC magic header */ | |
| 123 Uint8 signature[20]; /* "Creative Voice File\032" */ | |
| 124 Uint16 datablockofs; | |
| 125 | |
| 126 if (SDL_RWread(src, signature, sizeof (signature), 1) != 1) | |
| 127 return(0); | |
| 128 | |
| 129 if (memcmp(signature, "Creative Voice File\032", sizeof (signature)) != 0) { | |
| 130 Sound_SetError("Unrecognized file type (not VOC)"); | |
| 131 return(0); | |
| 132 } | |
| 133 | |
| 134 /* get the offset where the first datablock is located */ | |
| 135 if (SDL_RWread(src, &datablockofs, sizeof (Uint16), 1) != 1) | |
| 136 return(0); | |
| 137 | |
| 138 datablockofs = SDL_SwapLE16(datablockofs); | |
| 139 | |
| 140 if (SDL_RWseek(src, datablockofs, SEEK_SET) != datablockofs) | |
| 141 return(0); | |
| 142 | |
| 143 return(1); /* success! */ | |
| 144 } /* voc_check_header */ | |
| 145 | |
| 146 /* !!! FIXME : Add a flag to vs_t that distinguishes EOF and Error conditions. */ | |
| 147 | |
| 148 /* Read next block header, save info, leave position at start of data */ | |
| 149 static int voc_get_block(Sound_Sample *sample) | |
| 150 { | |
| 151 Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque; | |
| 152 SDL_RWops *src = internal->rw; | |
| 153 vs_t *v = (vs_t *) internal->decoder_private; | |
| 154 Uint8 bits24[3]; | |
| 155 Uint8 uc, block; | |
| 156 Uint32 sblen; | |
| 157 Uint16 new_rate_short; | |
| 158 Uint32 new_rate_long; | |
| 159 Uint8 trash[6]; | |
| 160 Uint16 period; | |
| 161 int i; | |
| 162 | |
| 163 v->silent = 0; | |
| 164 while (v->rest == 0) | |
| 165 { | |
| 166 if (SDL_RWread(src, &block, sizeof (block), 1) != 1) | |
| 167 return 1; /* assume that's the end of the file. */ | |
| 168 | |
| 169 if (block == VOC_TERM) | |
| 170 return 1; | |
| 171 | |
| 172 if (SDL_RWread(src, bits24, sizeof (bits24), 1) != 1) | |
| 173 return 1; /* assume that's the end of the file. */ | |
| 174 | |
| 175 /* Size is an 24-bit value. Ugh. */ | |
| 176 sblen = ( (bits24[0]) | (bits24[1] << 8) | (bits24[2] << 16) ); | |
| 177 | |
| 178 switch(block) | |
| 179 { | |
| 180 case VOC_DATA: | |
| 181 if (SDL_RWread(src, &uc, sizeof (uc), 1) != 1) | |
| 182 return 0; | |
| 183 | |
| 184 /* When DATA block preceeded by an EXTENDED */ | |
| 185 /* block, the DATA blocks rate value is invalid */ | |
| 186 if (!v->extended) | |
| 187 { | |
| 188 if (uc == 0) | |
| 189 { | |
| 190 Sound_SetError("VOC Sample rate is zero?"); | |
| 191 return 0; | |
| 192 } | |
| 193 | |
| 194 if ((v->rate != -1) && (uc != v->rate)) | |
| 195 { | |
| 196 Sound_SetError("VOC sample rate codes differ"); | |
| 197 return 0; | |
| 198 } | |
| 199 | |
| 200 v->rate = uc; | |
| 201 sample->actual.rate = 1000000.0/(256 - v->rate); | |
| 202 v->channels = 1; | |
| 203 } | |
| 204 | |
| 205 if (SDL_RWread(src, &uc, sizeof (uc), 1) != 1) | |
| 206 return 0; | |
| 207 | |
| 208 if (uc != 0) | |
| 209 { | |
| 210 Sound_SetError("VOC decoder only interprets 8-bit data"); | |
| 211 return 0; | |
| 212 } | |
| 213 | |
| 214 v->extended = 0; | |
| 215 v->rest = sblen - 2; | |
| 216 v->size = ST_SIZE_BYTE; | |
| 217 return 1; | |
| 218 | |
| 219 case VOC_DATA_16: | |
| 220 if (SDL_RWread(src, &new_rate_long, sizeof (new_rate_long), 1) != 1) | |
| 221 return 0; | |
| 222 new_rate_long = SDL_SwapLE32(new_rate_long); | |
| 223 if (new_rate_long == 0) | |
| 224 { | |
| 225 Sound_SetError("VOC Sample rate is zero?"); | |
| 226 return 0; | |
| 227 } | |
| 228 if ((v->rate != -1) && (new_rate_long != v->rate)) | |
| 229 { | |
| 230 Sound_SetError("VOC sample rate codes differ"); | |
| 231 return 0; | |
| 232 } | |
| 233 v->rate = new_rate_long; | |
| 234 sample->actual.rate = new_rate_long; | |
| 235 | |
| 236 if (SDL_RWread(src, &uc, sizeof (uc), 1) != 1) | |
| 237 return 0; | |
| 238 | |
| 239 switch (uc) | |
| 240 { | |
| 241 case 8: v->size = ST_SIZE_BYTE; break; | |
| 242 case 16: v->size = ST_SIZE_WORD; break; | |
| 243 default: | |
| 244 Sound_SetError("VOC with unknown data size"); | |
| 245 return 0; | |
| 246 } | |
| 247 | |
| 248 if (SDL_RWread(src, &v->channels, sizeof (Uint8), 1) != 1) | |
| 249 return 0; | |
| 250 | |
| 251 if (SDL_RWread(src, trash, sizeof (Uint8), 6) != 6) | |
| 252 return 0; | |
| 253 | |
| 254 v->rest = sblen - 12; | |
| 255 return 1; | |
| 256 | |
| 257 case VOC_CONT: | |
| 258 v->rest = sblen; | |
| 259 return 1; | |
| 260 | |
| 261 case VOC_SILENCE: | |
| 262 if (SDL_RWread(src, &period, sizeof (period), 1) != 1) | |
| 263 return 0; | |
| 264 period = SDL_SwapLE16(period); | |
| 265 | |
| 266 if (SDL_RWread(src, &uc, sizeof (uc), 1) != 1) | |
| 267 return 0; | |
| 268 if (uc == 0) | |
| 269 { | |
| 270 Sound_SetError("VOC silence sample rate is zero"); | |
| 271 return 0; | |
| 272 } | |
| 273 | |
| 274 /* | |
| 275 * Some silence-packed files have gratuitously | |
| 276 * different sample rate codes in silence. | |
| 277 * Adjust period. | |
| 278 */ | |
| 279 if ((v->rate != -1) && (uc != v->rate)) | |
| 280 period = (period * (256 - uc))/(256 - v->rate); | |
| 281 else | |
| 282 v->rate = uc; | |
| 283 v->rest = period; | |
| 284 v->silent = 1; | |
| 285 return 1; | |
| 286 | |
| 287 case VOC_LOOP: | |
| 288 case VOC_LOOPEND: | |
| 289 for(i = 0; i < sblen; i++) /* skip repeat loops. */ | |
| 290 { | |
| 291 if (SDL_RWread(src, trash, sizeof (Uint8), 1) != 1) | |
| 292 return 0; | |
| 293 } | |
| 294 break; | |
| 295 | |
| 296 case VOC_EXTENDED: | |
| 297 /* An Extended block is followed by a data block */ | |
| 298 /* Set this byte so we know to use the rate */ | |
| 299 /* value from the extended block and not the */ | |
| 300 /* data block. */ | |
| 301 v->extended = 1; | |
| 302 if (SDL_RWread(src, &new_rate_short, sizeof (new_rate_short), 1) != 1) | |
| 303 return 0; | |
| 304 new_rate_short = SDL_SwapLE16(new_rate_short); | |
| 305 if (new_rate_short == 0) | |
| 306 { | |
| 307 Sound_SetError("VOC sample rate is zero"); | |
| 308 return 0; | |
| 309 } | |
| 310 if ((v->rate != -1) && (new_rate_short != v->rate)) | |
| 311 { | |
| 312 Sound_SetError("VOC sample rate codes differ"); | |
| 313 return 0; | |
| 314 } | |
| 315 v->rate = new_rate_short; | |
| 316 | |
| 317 if (SDL_RWread(src, &uc, sizeof (uc), 1) != 1) | |
| 318 return 0; | |
| 319 | |
| 320 if (uc != 0) | |
| 321 { | |
| 322 Sound_SetError("VOC decoder only interprets 8-bit data"); | |
| 323 return 0; | |
| 324 } | |
| 325 | |
| 326 if (SDL_RWread(src, &uc, sizeof (uc), 1) != 1) | |
| 327 return 0; | |
| 328 | |
| 329 if (uc) | |
| 330 sample->actual.channels = 2; /* Stereo */ | |
| 331 /* Needed number of channels before finishing | |
| 332 compute for rate */ | |
| 333 sample->actual.rate = | |
| 334 (256000000L/(65536L - v->rate)) / sample->actual.channels; | |
| 335 /* An extended block must be followed by a data */ | |
| 336 /* block to be valid so loop back to top so it */ | |
| 337 /* can be grabed. */ | |
| 338 continue; | |
| 339 | |
| 340 case VOC_MARKER: | |
| 341 if (SDL_RWread(src, trash, sizeof (Uint8), 2) != 2) | |
| 342 return 0; | |
| 343 | |
| 344 /* Falling! Falling! */ | |
| 345 | |
| 346 default: /* text block or other krapola. */ | |
| 347 for(i = 0; i < sblen; i++) | |
| 348 { | |
| 349 if (SDL_RWread(src, &trash, sizeof (Uint8), 1) != 1) | |
| 350 return 0; | |
| 351 } | |
| 352 | |
| 353 if (block == VOC_TEXT) | |
| 354 continue; /* get next block */ | |
| 355 } | |
| 356 } | |
| 357 | |
| 358 return 1; | |
| 359 } | |
| 360 | |
| 361 | |
|
22
f6e679afe88b
Byte ordering fix, changed voc_read to voc_read_waveform, and cleaned up
Ryan C. Gordon <icculus@icculus.org>
parents:
14
diff
changeset
|
362 static int voc_read_waveform(Sound_Sample *sample) |
| 14 | 363 { |
| 364 Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque; | |
| 365 SDL_RWops *src = internal->rw; | |
| 366 vs_t *v = (vs_t *) internal->decoder_private; | |
| 367 int done = 0; | |
| 368 Uint8 silence = 0x80; | |
| 369 Uint8 *buf = internal->buffer; | |
| 370 | |
| 371 if (v->rest == 0) | |
| 372 { | |
| 373 if (!voc_get_block(sample)) | |
| 374 return 0; | |
| 375 } | |
| 376 | |
| 377 if (v->rest == 0) | |
| 378 return 0; | |
| 379 | |
| 380 if (v->silent) | |
| 381 { | |
| 382 if (v->size == ST_SIZE_WORD) | |
| 383 silence = 0x00; | |
| 384 | |
| 385 /* Fill in silence */ | |
| 386 memset(buf, silence, v->rest); | |
| 387 done = v->rest; | |
| 388 v->rest = 0; | |
| 389 } | |
| 390 | |
| 391 else | |
| 392 { | |
| 393 Uint32 max = (v->rest < internal->buffer_size) ? | |
| 394 v->rest : internal->buffer_size; | |
| 395 done = SDL_RWread(src, buf + v->bufpos, 1, max); | |
| 396 v->rest -= done; | |
| 397 v->bufpos += done; | |
| 398 } | |
| 399 | |
| 400 return done; | |
|
22
f6e679afe88b
Byte ordering fix, changed voc_read to voc_read_waveform, and cleaned up
Ryan C. Gordon <icculus@icculus.org>
parents:
14
diff
changeset
|
401 } /* voc_read_waveform */ |
| 14 | 402 |
| 403 | |
| 404 static int VOC_open(Sound_Sample *sample, const char *ext) | |
| 405 { | |
| 406 Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque; | |
| 407 vs_t *v = NULL; | |
| 408 | |
| 409 if (!voc_check_header(internal->rw)) | |
| 410 return(0); | |
| 411 | |
| 412 v = (vs_t *) malloc(sizeof (vs_t)); | |
| 413 BAIL_IF_MACRO(v == NULL, ERR_OUT_OF_MEMORY, 0); | |
| 414 memset(v, '\0', sizeof (vs_t)); | |
| 415 internal->decoder_private = v; | |
| 416 | |
| 417 v->rate = -1; | |
| 418 if (!voc_get_block(sample)) | |
| 419 { | |
| 420 free(v); | |
| 421 return(0); | |
| 422 } /* if */ | |
| 423 | |
| 424 if (v->rate == -1) | |
| 425 { | |
| 426 Sound_SetError("VOC data had no sound!"); | |
| 427 free(v); | |
| 428 return(0); | |
| 429 } /* if */ | |
| 430 | |
| 431 _D(("VOC: Accepting data stream.\n")); | |
| 432 sample->actual.format = (v->size == ST_SIZE_WORD) ? AUDIO_S16LSB:AUDIO_U8; | |
| 433 sample->actual.channels = v->channels; | |
| 434 sample->flags = SOUND_SAMPLEFLAG_NONE; | |
| 435 return(1); | |
| 436 } /* VOC_open */ | |
| 437 | |
| 438 | |
| 439 static void VOC_close(Sound_Sample *sample) | |
| 440 { | |
| 441 Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque; | |
| 442 free(internal->decoder_private); | |
| 443 } /* VOC_close */ | |
| 444 | |
| 445 | |
| 446 static Uint32 VOC_read(Sound_Sample *sample) | |
| 447 { | |
| 448 Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque; | |
| 449 vs_t *v = (vs_t *) internal->decoder_private; | |
| 450 | |
| 451 v->bufpos = 0; | |
| 452 while (v->bufpos < internal->buffer_size) | |
| 453 { | |
|
22
f6e679afe88b
Byte ordering fix, changed voc_read to voc_read_waveform, and cleaned up
Ryan C. Gordon <icculus@icculus.org>
parents:
14
diff
changeset
|
454 Uint32 rc = voc_read_waveform(sample); |
| 14 | 455 if (rc == 0) /* !!! FIXME: Could be an error... */ |
| 456 { | |
| 457 sample->flags |= SOUND_SAMPLEFLAG_EOF; | |
| 458 break; | |
| 459 } /* if */ | |
| 460 | |
| 461 if (!voc_get_block(sample)) | |
| 462 { | |
| 463 sample->flags |= SOUND_SAMPLEFLAG_ERROR; | |
| 464 break; | |
| 465 } /* if */ | |
| 466 } /* while */ | |
| 467 | |
| 468 return(v->bufpos); | |
| 469 } /* VOC_read */ | |
| 470 | |
| 471 | |
| 472 /* end of voc.c ... */ | |
| 473 |