Alexandre Lision | 7c6f4a6 | 2013-09-05 13:27:01 -0400 | [diff] [blame] | 1 | /* |
| 2 | ** Copyright (C) 2003-2011 Erik de Castro Lopo <erikd@mega-nerd.com> |
| 3 | ** |
| 4 | ** This program is free software; you can redistribute it and/or modify |
| 5 | ** it under the terms of the GNU Lesser General Public License as published by |
| 6 | ** the Free Software Foundation; either version 2.1 of the License, or |
| 7 | ** (at your option) any later version. |
| 8 | ** |
| 9 | ** This program is distributed in the hope that it will be useful, |
| 10 | ** but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | ** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 12 | ** GNU Lesser General Public License for more details. |
| 13 | ** |
| 14 | ** You should have received a copy of the GNU Lesser General Public License |
| 15 | ** along with this program; if not, write to the Free Software |
| 16 | ** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 17 | */ |
| 18 | |
| 19 | #include "sfconfig.h" |
| 20 | |
| 21 | #include <stdlib.h> |
| 22 | |
| 23 | #include "sndfile.h" |
| 24 | #include "sfendian.h" |
| 25 | #include "common.h" |
| 26 | |
| 27 | /*============================================================================ |
| 28 | ** Rule number 1 is to only apply dither when going from a larger bitwidth |
| 29 | ** to a smaller bitwidth. This can happen on both read and write. |
| 30 | ** |
| 31 | ** Need to apply dither on all conversions marked X below. |
| 32 | ** |
| 33 | ** Dither on write: |
| 34 | ** |
| 35 | ** Input |
| 36 | ** | short int float double |
| 37 | ** --------+----------------------------------------------- |
| 38 | ** O 8 bit | X X X X |
| 39 | ** u 16 bit | none X X X |
| 40 | ** t 24 bit | none X X X |
| 41 | ** p 32 bit | none none X X |
| 42 | ** u float | none none none none |
| 43 | ** t double | none none none none |
| 44 | ** |
| 45 | ** Dither on read: |
| 46 | ** |
| 47 | ** Input |
| 48 | ** O | 8 bit 16 bit 24 bit 32 bit float double |
| 49 | ** u --------+------------------------------------------------- |
| 50 | ** t short | none none X X X X |
| 51 | ** p int | none none none X X X |
| 52 | ** u float | none none none none none none |
| 53 | ** t double | none none none none none none |
| 54 | */ |
| 55 | |
| 56 | #define SFE_DITHER_BAD_PTR 666 |
| 57 | #define SFE_DITHER_BAD_TYPE 667 |
| 58 | |
| 59 | typedef struct |
| 60 | { int read_short_dither_bits, read_int_dither_bits ; |
| 61 | int write_short_dither_bits, write_int_dither_bits ; |
| 62 | double read_float_dither_scale, read_double_dither_bits ; |
| 63 | double write_float_dither_scale, write_double_dither_bits ; |
| 64 | |
| 65 | sf_count_t (*read_short) (SF_PRIVATE *psf, short *ptr, sf_count_t len) ; |
| 66 | sf_count_t (*read_int) (SF_PRIVATE *psf, int *ptr, sf_count_t len) ; |
| 67 | sf_count_t (*read_float) (SF_PRIVATE *psf, float *ptr, sf_count_t len) ; |
| 68 | sf_count_t (*read_double) (SF_PRIVATE *psf, double *ptr, sf_count_t len) ; |
| 69 | |
| 70 | sf_count_t (*write_short) (SF_PRIVATE *psf, const short *ptr, sf_count_t len) ; |
| 71 | sf_count_t (*write_int) (SF_PRIVATE *psf, const int *ptr, sf_count_t len) ; |
| 72 | sf_count_t (*write_float) (SF_PRIVATE *psf, const float *ptr, sf_count_t len) ; |
| 73 | sf_count_t (*write_double) (SF_PRIVATE *psf, const double *ptr, sf_count_t len) ; |
| 74 | |
| 75 | double buffer [SF_BUFFER_LEN / sizeof (double)] ; |
| 76 | } DITHER_DATA ; |
| 77 | |
| 78 | static sf_count_t dither_read_short (SF_PRIVATE *psf, short *ptr, sf_count_t len) ; |
| 79 | static sf_count_t dither_read_int (SF_PRIVATE *psf, int *ptr, sf_count_t len) ; |
| 80 | |
| 81 | static sf_count_t dither_write_short (SF_PRIVATE *psf, const short *ptr, sf_count_t len) ; |
| 82 | static sf_count_t dither_write_int (SF_PRIVATE *psf, const int *ptr, sf_count_t len) ; |
| 83 | static sf_count_t dither_write_float (SF_PRIVATE *psf, const float *ptr, sf_count_t len) ; |
| 84 | static sf_count_t dither_write_double (SF_PRIVATE *psf, const double *ptr, sf_count_t len) ; |
| 85 | |
| 86 | int |
| 87 | dither_init (SF_PRIVATE *psf, int mode) |
| 88 | { DITHER_DATA *pdither ; |
| 89 | |
| 90 | pdither = psf->dither ; /* This may be NULL. */ |
| 91 | |
| 92 | /* Turn off dither on read. */ |
| 93 | if (mode == SFM_READ && psf->read_dither.type == SFD_NO_DITHER) |
| 94 | { if (pdither == NULL) |
| 95 | return 0 ; /* Dither is already off, so just return. */ |
| 96 | |
| 97 | if (pdither->read_short) |
| 98 | psf->read_short = pdither->read_short ; |
| 99 | if (pdither->read_int) |
| 100 | psf->read_int = pdither->read_int ; |
| 101 | if (pdither->read_float) |
| 102 | psf->read_float = pdither->read_float ; |
| 103 | if (pdither->read_double) |
| 104 | psf->read_double = pdither->read_double ; |
| 105 | return 0 ; |
| 106 | } ; |
| 107 | |
| 108 | /* Turn off dither on write. */ |
| 109 | if (mode == SFM_WRITE && psf->write_dither.type == SFD_NO_DITHER) |
| 110 | { if (pdither == NULL) |
| 111 | return 0 ; /* Dither is already off, so just return. */ |
| 112 | |
| 113 | if (pdither->write_short) |
| 114 | psf->write_short = pdither->write_short ; |
| 115 | if (pdither->write_int) |
| 116 | psf->write_int = pdither->write_int ; |
| 117 | if (pdither->write_float) |
| 118 | psf->write_float = pdither->write_float ; |
| 119 | if (pdither->write_double) |
| 120 | psf->write_double = pdither->write_double ; |
| 121 | return 0 ; |
| 122 | } ; |
| 123 | |
| 124 | /* Turn on dither on read if asked. */ |
| 125 | if (mode == SFM_READ && psf->read_dither.type != 0) |
| 126 | { if (pdither == NULL) |
| 127 | pdither = psf->dither = calloc (1, sizeof (DITHER_DATA)) ; |
| 128 | if (pdither == NULL) |
| 129 | return SFE_MALLOC_FAILED ; |
| 130 | |
| 131 | switch (SF_CODEC (psf->sf.format)) |
| 132 | { case SF_FORMAT_DOUBLE : |
| 133 | case SF_FORMAT_FLOAT : |
| 134 | pdither->read_int = psf->read_int ; |
| 135 | psf->read_int = dither_read_int ; |
| 136 | break ; |
| 137 | |
| 138 | case SF_FORMAT_PCM_32 : |
| 139 | case SF_FORMAT_PCM_24 : |
| 140 | case SF_FORMAT_PCM_16 : |
| 141 | case SF_FORMAT_PCM_S8 : |
| 142 | case SF_FORMAT_PCM_U8 : |
| 143 | pdither->read_short = psf->read_short ; |
| 144 | psf->read_short = dither_read_short ; |
| 145 | break ; |
| 146 | |
| 147 | default : break ; |
| 148 | } ; |
| 149 | } ; |
| 150 | |
| 151 | /* Turn on dither on write if asked. */ |
| 152 | if (mode == SFM_WRITE && psf->write_dither.type != 0) |
| 153 | { if (pdither == NULL) |
| 154 | pdither = psf->dither = calloc (1, sizeof (DITHER_DATA)) ; |
| 155 | if (pdither == NULL) |
| 156 | return SFE_MALLOC_FAILED ; |
| 157 | |
| 158 | switch (SF_CODEC (psf->sf.format)) |
| 159 | { case SF_FORMAT_DOUBLE : |
| 160 | case SF_FORMAT_FLOAT : |
| 161 | pdither->write_int = psf->write_int ; |
| 162 | psf->write_int = dither_write_int ; |
| 163 | break ; |
| 164 | |
| 165 | case SF_FORMAT_PCM_32 : |
| 166 | case SF_FORMAT_PCM_24 : |
| 167 | case SF_FORMAT_PCM_16 : |
| 168 | case SF_FORMAT_PCM_S8 : |
| 169 | case SF_FORMAT_PCM_U8 : |
| 170 | break ; |
| 171 | |
| 172 | default : break ; |
| 173 | } ; |
| 174 | |
| 175 | pdither->write_short = psf->write_short ; |
| 176 | psf->write_short = dither_write_short ; |
| 177 | |
| 178 | pdither->write_int = psf->write_int ; |
| 179 | psf->write_int = dither_write_int ; |
| 180 | |
| 181 | pdither->write_float = psf->write_float ; |
| 182 | psf->write_float = dither_write_float ; |
| 183 | |
| 184 | pdither->write_double = psf->write_double ; |
| 185 | psf->write_double = dither_write_double ; |
| 186 | } ; |
| 187 | |
| 188 | return 0 ; |
| 189 | } /* dither_init */ |
| 190 | |
| 191 | /*============================================================================== |
| 192 | */ |
| 193 | |
| 194 | static void dither_short (const short *in, short *out, int frames, int channels) ; |
| 195 | static void dither_int (const int *in, int *out, int frames, int channels) ; |
| 196 | |
| 197 | static void dither_float (const float *in, float *out, int frames, int channels) ; |
| 198 | static void dither_double (const double *in, double *out, int frames, int channels) ; |
| 199 | |
| 200 | static sf_count_t |
| 201 | dither_read_short (SF_PRIVATE * UNUSED (psf), short * UNUSED (ptr), sf_count_t len) |
| 202 | { |
| 203 | return len ; |
| 204 | } /* dither_read_short */ |
| 205 | |
| 206 | static sf_count_t |
| 207 | dither_read_int (SF_PRIVATE * UNUSED (psf), int * UNUSED (ptr), sf_count_t len) |
| 208 | { |
| 209 | return len ; |
| 210 | } /* dither_read_int */ |
| 211 | |
| 212 | /*------------------------------------------------------------------------------ |
| 213 | */ |
| 214 | |
| 215 | static sf_count_t |
| 216 | dither_write_short (SF_PRIVATE *psf, const short *ptr, sf_count_t len) |
| 217 | { DITHER_DATA *pdither ; |
| 218 | int bufferlen, writecount, thiswrite ; |
| 219 | sf_count_t total = 0 ; |
| 220 | |
| 221 | if ((pdither = psf->dither) == NULL) |
| 222 | { psf->error = SFE_DITHER_BAD_PTR ; |
| 223 | return 0 ; |
| 224 | } ; |
| 225 | |
| 226 | switch (SF_CODEC (psf->sf.format)) |
| 227 | { case SF_FORMAT_PCM_S8 : |
| 228 | case SF_FORMAT_PCM_U8 : |
| 229 | case SF_FORMAT_DPCM_8 : |
| 230 | break ; |
| 231 | |
| 232 | default : |
| 233 | return pdither->write_short (psf, ptr, len) ; |
| 234 | } ; |
| 235 | |
| 236 | bufferlen = sizeof (pdither->buffer) / sizeof (short) ; |
| 237 | |
| 238 | while (len > 0) |
| 239 | { writecount = (len >= bufferlen) ? bufferlen : (int) len ; |
| 240 | writecount /= psf->sf.channels ; |
| 241 | writecount *= psf->sf.channels ; |
| 242 | |
| 243 | dither_short (ptr, (short*) pdither->buffer, writecount / psf->sf.channels, psf->sf.channels) ; |
| 244 | |
| 245 | thiswrite = pdither->write_short (psf, (short*) pdither->buffer, writecount) ; |
| 246 | total += thiswrite ; |
| 247 | len -= thiswrite ; |
| 248 | if (thiswrite < writecount) |
| 249 | break ; |
| 250 | } ; |
| 251 | |
| 252 | return total ; |
| 253 | } /* dither_write_short */ |
| 254 | |
| 255 | static sf_count_t |
| 256 | dither_write_int (SF_PRIVATE *psf, const int *ptr, sf_count_t len) |
| 257 | { DITHER_DATA *pdither ; |
| 258 | int bufferlen, writecount, thiswrite ; |
| 259 | sf_count_t total = 0 ; |
| 260 | |
| 261 | if ((pdither = psf->dither) == NULL) |
| 262 | { psf->error = SFE_DITHER_BAD_PTR ; |
| 263 | return 0 ; |
| 264 | } ; |
| 265 | |
| 266 | switch (SF_CODEC (psf->sf.format)) |
| 267 | { case SF_FORMAT_PCM_S8 : |
| 268 | case SF_FORMAT_PCM_U8 : |
| 269 | case SF_FORMAT_PCM_16 : |
| 270 | case SF_FORMAT_PCM_24 : |
| 271 | break ; |
| 272 | |
| 273 | case SF_FORMAT_DPCM_8 : |
| 274 | case SF_FORMAT_DPCM_16 : |
| 275 | break ; |
| 276 | |
| 277 | default : |
| 278 | return pdither->write_int (psf, ptr, len) ; |
| 279 | } ; |
| 280 | |
| 281 | |
| 282 | bufferlen = sizeof (pdither->buffer) / sizeof (int) ; |
| 283 | |
| 284 | while (len > 0) |
| 285 | { writecount = (len >= bufferlen) ? bufferlen : (int) len ; |
| 286 | writecount /= psf->sf.channels ; |
| 287 | writecount *= psf->sf.channels ; |
| 288 | |
| 289 | dither_int (ptr, (int*) pdither->buffer, writecount / psf->sf.channels, psf->sf.channels) ; |
| 290 | |
| 291 | thiswrite = pdither->write_int (psf, (int*) pdither->buffer, writecount) ; |
| 292 | total += thiswrite ; |
| 293 | len -= thiswrite ; |
| 294 | if (thiswrite < writecount) |
| 295 | break ; |
| 296 | } ; |
| 297 | |
| 298 | return total ; |
| 299 | } /* dither_write_int */ |
| 300 | |
| 301 | static sf_count_t |
| 302 | dither_write_float (SF_PRIVATE *psf, const float *ptr, sf_count_t len) |
| 303 | { DITHER_DATA *pdither ; |
| 304 | int bufferlen, writecount, thiswrite ; |
| 305 | sf_count_t total = 0 ; |
| 306 | |
| 307 | if ((pdither = psf->dither) == NULL) |
| 308 | { psf->error = SFE_DITHER_BAD_PTR ; |
| 309 | return 0 ; |
| 310 | } ; |
| 311 | |
| 312 | switch (SF_CODEC (psf->sf.format)) |
| 313 | { case SF_FORMAT_PCM_S8 : |
| 314 | case SF_FORMAT_PCM_U8 : |
| 315 | case SF_FORMAT_PCM_16 : |
| 316 | case SF_FORMAT_PCM_24 : |
| 317 | break ; |
| 318 | |
| 319 | case SF_FORMAT_DPCM_8 : |
| 320 | case SF_FORMAT_DPCM_16 : |
| 321 | break ; |
| 322 | |
| 323 | default : |
| 324 | return pdither->write_float (psf, ptr, len) ; |
| 325 | } ; |
| 326 | |
| 327 | bufferlen = sizeof (pdither->buffer) / sizeof (float) ; |
| 328 | |
| 329 | while (len > 0) |
| 330 | { writecount = (len >= bufferlen) ? bufferlen : (float) len ; |
| 331 | writecount /= psf->sf.channels ; |
| 332 | writecount *= psf->sf.channels ; |
| 333 | |
| 334 | dither_float (ptr, (float*) pdither->buffer, writecount / psf->sf.channels, psf->sf.channels) ; |
| 335 | |
| 336 | thiswrite = pdither->write_float (psf, (float*) pdither->buffer, writecount) ; |
| 337 | total += thiswrite ; |
| 338 | len -= thiswrite ; |
| 339 | if (thiswrite < writecount) |
| 340 | break ; |
| 341 | } ; |
| 342 | |
| 343 | return total ; |
| 344 | } /* dither_write_float */ |
| 345 | |
| 346 | static sf_count_t |
| 347 | dither_write_double (SF_PRIVATE *psf, const double *ptr, sf_count_t len) |
| 348 | { DITHER_DATA *pdither ; |
| 349 | int bufferlen, writecount, thiswrite ; |
| 350 | sf_count_t total = 0 ; |
| 351 | |
| 352 | if ((pdither = psf->dither) == NULL) |
| 353 | { psf->error = SFE_DITHER_BAD_PTR ; |
| 354 | return 0 ; |
| 355 | } ; |
| 356 | |
| 357 | switch (SF_CODEC (psf->sf.format)) |
| 358 | { case SF_FORMAT_PCM_S8 : |
| 359 | case SF_FORMAT_PCM_U8 : |
| 360 | case SF_FORMAT_PCM_16 : |
| 361 | case SF_FORMAT_PCM_24 : |
| 362 | break ; |
| 363 | |
| 364 | case SF_FORMAT_DPCM_8 : |
| 365 | case SF_FORMAT_DPCM_16 : |
| 366 | break ; |
| 367 | |
| 368 | default : |
| 369 | return pdither->write_double (psf, ptr, len) ; |
| 370 | } ; |
| 371 | |
| 372 | |
| 373 | bufferlen = sizeof (pdither->buffer) / sizeof (double) ; |
| 374 | |
| 375 | while (len > 0) |
| 376 | { writecount = (len >= bufferlen) ? bufferlen : (double) len ; |
| 377 | writecount /= psf->sf.channels ; |
| 378 | writecount *= psf->sf.channels ; |
| 379 | |
| 380 | dither_double (ptr, (double*) pdither->buffer, writecount / psf->sf.channels, psf->sf.channels) ; |
| 381 | |
| 382 | thiswrite = pdither->write_double (psf, (double*) pdither->buffer, writecount) ; |
| 383 | total += thiswrite ; |
| 384 | len -= thiswrite ; |
| 385 | if (thiswrite < writecount) |
| 386 | break ; |
| 387 | } ; |
| 388 | |
| 389 | return total ; |
| 390 | } /* dither_write_double */ |
| 391 | |
| 392 | /*============================================================================== |
| 393 | */ |
| 394 | |
| 395 | static void |
| 396 | dither_short (const short *in, short *out, int frames, int channels) |
| 397 | { int ch, k ; |
| 398 | |
| 399 | for (ch = 0 ; ch < channels ; ch++) |
| 400 | for (k = ch ; k < channels * frames ; k += channels) |
| 401 | out [k] = in [k] ; |
| 402 | |
| 403 | } /* dither_short */ |
| 404 | |
| 405 | static void |
| 406 | dither_int (const int *in, int *out, int frames, int channels) |
| 407 | { int ch, k ; |
| 408 | |
| 409 | for (ch = 0 ; ch < channels ; ch++) |
| 410 | for (k = ch ; k < channels * frames ; k += channels) |
| 411 | out [k] = in [k] ; |
| 412 | |
| 413 | } /* dither_int */ |
| 414 | |
| 415 | static void |
| 416 | dither_float (const float *in, float *out, int frames, int channels) |
| 417 | { int ch, k ; |
| 418 | |
| 419 | for (ch = 0 ; ch < channels ; ch++) |
| 420 | for (k = ch ; k < channels * frames ; k += channels) |
| 421 | out [k] = in [k] ; |
| 422 | |
| 423 | } /* dither_float */ |
| 424 | |
| 425 | static void |
| 426 | dither_double (const double *in, double *out, int frames, int channels) |
| 427 | { int ch, k ; |
| 428 | |
| 429 | for (ch = 0 ; ch < channels ; ch++) |
| 430 | for (k = ch ; k < channels * frames ; k += channels) |
| 431 | out [k] = in [k] ; |
| 432 | |
| 433 | } /* dither_double */ |
| 434 | |
| 435 | /*============================================================================== |
| 436 | */ |
| 437 | #if 0 |
| 438 | |
| 439 | /* |
| 440 | ** Not made public because this (maybe) requires storage of state information. |
| 441 | ** |
| 442 | ** Also maybe need separate state info for each channel!!!! |
| 443 | */ |
| 444 | |
| 445 | int |
| 446 | DO_NOT_USE_sf_dither_short (const SF_DITHER_INFO *dither, const short *in, short *out, int frames, int channels) |
| 447 | { int ch, k ; |
| 448 | |
| 449 | if (! dither) |
| 450 | return SFE_DITHER_BAD_PTR ; |
| 451 | |
| 452 | switch (dither->type & SFD_TYPEMASK) |
| 453 | { case SFD_WHITE : |
| 454 | case SFD_TRIANGULAR_PDF : |
| 455 | for (ch = 0 ; ch < channels ; ch++) |
| 456 | for (k = ch ; k < channels * frames ; k += channels) |
| 457 | out [k] = in [k] ; |
| 458 | break ; |
| 459 | |
| 460 | default : |
| 461 | return SFE_DITHER_BAD_TYPE ; |
| 462 | } ; |
| 463 | |
| 464 | return 0 ; |
| 465 | } /* DO_NOT_USE_sf_dither_short */ |
| 466 | |
| 467 | int |
| 468 | DO_NOT_USE_sf_dither_int (const SF_DITHER_INFO *dither, const int *in, int *out, int frames, int channels) |
| 469 | { int ch, k ; |
| 470 | |
| 471 | if (! dither) |
| 472 | return SFE_DITHER_BAD_PTR ; |
| 473 | |
| 474 | switch (dither->type & SFD_TYPEMASK) |
| 475 | { case SFD_WHITE : |
| 476 | case SFD_TRIANGULAR_PDF : |
| 477 | for (ch = 0 ; ch < channels ; ch++) |
| 478 | for (k = ch ; k < channels * frames ; k += channels) |
| 479 | out [k] = in [k] ; |
| 480 | break ; |
| 481 | |
| 482 | default : |
| 483 | return SFE_DITHER_BAD_TYPE ; |
| 484 | } ; |
| 485 | |
| 486 | return 0 ; |
| 487 | } /* DO_NOT_USE_sf_dither_int */ |
| 488 | |
| 489 | int |
| 490 | DO_NOT_USE_sf_dither_float (const SF_DITHER_INFO *dither, const float *in, float *out, int frames, int channels) |
| 491 | { int ch, k ; |
| 492 | |
| 493 | if (! dither) |
| 494 | return SFE_DITHER_BAD_PTR ; |
| 495 | |
| 496 | switch (dither->type & SFD_TYPEMASK) |
| 497 | { case SFD_WHITE : |
| 498 | case SFD_TRIANGULAR_PDF : |
| 499 | for (ch = 0 ; ch < channels ; ch++) |
| 500 | for (k = ch ; k < channels * frames ; k += channels) |
| 501 | out [k] = in [k] ; |
| 502 | break ; |
| 503 | |
| 504 | default : |
| 505 | return SFE_DITHER_BAD_TYPE ; |
| 506 | } ; |
| 507 | |
| 508 | return 0 ; |
| 509 | } /* DO_NOT_USE_sf_dither_float */ |
| 510 | |
| 511 | int |
| 512 | DO_NOT_USE_sf_dither_double (const SF_DITHER_INFO *dither, const double *in, double *out, int frames, int channels) |
| 513 | { int ch, k ; |
| 514 | |
| 515 | if (! dither) |
| 516 | return SFE_DITHER_BAD_PTR ; |
| 517 | |
| 518 | switch (dither->type & SFD_TYPEMASK) |
| 519 | { case SFD_WHITE : |
| 520 | case SFD_TRIANGULAR_PDF : |
| 521 | for (ch = 0 ; ch < channels ; ch++) |
| 522 | for (k = ch ; k < channels * frames ; k += channels) |
| 523 | out [k] = in [k] ; |
| 524 | break ; |
| 525 | |
| 526 | default : |
| 527 | return SFE_DITHER_BAD_TYPE ; |
| 528 | } ; |
| 529 | |
| 530 | return 0 ; |
| 531 | } /* DO_NOT_USE_sf_dither_double */ |
| 532 | |
| 533 | #endif |
| 534 | |