Emeric Vigier | eebea67 | 2012-08-06 17:36:30 -0400 | [diff] [blame] | 1 | /* |
| 2 | ** Copyright (C) 2002-2011 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 General Public License as published by |
| 6 | ** the Free Software Foundation; either version 2 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 General Public License for more details. |
| 13 | ** |
| 14 | ** You should have received a copy of the GNU 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 | /* |
| 20 | ** This code is part of Secret Rabbit Code aka libsamplerate. A commercial |
| 21 | ** use license for this code is available, please see: |
| 22 | ** http://www.mega-nerd.com/SRC/procedure.html |
| 23 | */ |
| 24 | |
| 25 | #include <stdio.h> |
| 26 | #include <stdlib.h> |
| 27 | #include <string.h> |
| 28 | |
| 29 | #include "config.h" |
| 30 | #include "float_cast.h" |
| 31 | #include "common.h" |
| 32 | |
| 33 | #define SINC_MAGIC_MARKER MAKE_MAGIC (' ', 's', 'i', 'n', 'c', ' ') |
| 34 | |
| 35 | /*======================================================================================== |
| 36 | */ |
| 37 | |
| 38 | #define MAKE_INCREMENT_T(x) ((increment_t) (x)) |
| 39 | |
| 40 | #define SHIFT_BITS 12 |
| 41 | #define FP_ONE ((double) (((increment_t) 1) << SHIFT_BITS)) |
| 42 | #define INV_FP_ONE (1.0 / FP_ONE) |
| 43 | |
| 44 | /*======================================================================================== |
| 45 | */ |
| 46 | |
| 47 | typedef int32_t increment_t ; |
| 48 | typedef float coeff_t ; |
| 49 | |
| 50 | #include "fastest_coeffs.h" |
| 51 | #include "mid_qual_coeffs.h" |
| 52 | #include "high_qual_coeffs.h" |
| 53 | |
| 54 | typedef struct |
| 55 | { int sinc_magic_marker ; |
| 56 | |
| 57 | int channels ; |
| 58 | long in_count, in_used ; |
| 59 | long out_count, out_gen ; |
| 60 | |
| 61 | int coeff_half_len, index_inc ; |
| 62 | |
| 63 | double src_ratio, input_index ; |
| 64 | |
| 65 | coeff_t const *coeffs ; |
| 66 | |
| 67 | int b_current, b_end, b_real_end, b_len ; |
| 68 | |
| 69 | /* Sure hope noone does more than 128 channels at once. */ |
| 70 | double left_calc [128], right_calc [128] ; |
| 71 | |
| 72 | /* C99 struct flexible array. */ |
| 73 | float buffer [] ; |
| 74 | } SINC_FILTER ; |
| 75 | |
| 76 | static int sinc_multichan_vari_process (SRC_PRIVATE *psrc, SRC_DATA *data) ; |
| 77 | static int sinc_hex_vari_process (SRC_PRIVATE *psrc, SRC_DATA *data) ; |
| 78 | static int sinc_quad_vari_process (SRC_PRIVATE *psrc, SRC_DATA *data) ; |
| 79 | static int sinc_stereo_vari_process (SRC_PRIVATE *psrc, SRC_DATA *data) ; |
| 80 | static int sinc_mono_vari_process (SRC_PRIVATE *psrc, SRC_DATA *data) ; |
| 81 | |
| 82 | static int prepare_data (SINC_FILTER *filter, SRC_DATA *data, int half_filter_chan_len) WARN_UNUSED ; |
| 83 | |
| 84 | static void sinc_reset (SRC_PRIVATE *psrc) ; |
| 85 | |
| 86 | static inline increment_t |
| 87 | double_to_fp (double x) |
| 88 | { return (lrint ((x) * FP_ONE)) ; |
| 89 | } /* double_to_fp */ |
| 90 | |
| 91 | static inline increment_t |
| 92 | int_to_fp (int x) |
| 93 | { return (((increment_t) (x)) << SHIFT_BITS) ; |
| 94 | } /* int_to_fp */ |
| 95 | |
| 96 | static inline int |
| 97 | fp_to_int (increment_t x) |
| 98 | { return (((x) >> SHIFT_BITS)) ; |
| 99 | } /* fp_to_int */ |
| 100 | |
| 101 | static inline increment_t |
| 102 | fp_fraction_part (increment_t x) |
| 103 | { return ((x) & ((((increment_t) 1) << SHIFT_BITS) - 1)) ; |
| 104 | } /* fp_fraction_part */ |
| 105 | |
| 106 | static inline double |
| 107 | fp_to_double (increment_t x) |
| 108 | { return fp_fraction_part (x) * INV_FP_ONE ; |
| 109 | } /* fp_to_double */ |
| 110 | |
| 111 | |
| 112 | /*---------------------------------------------------------------------------------------- |
| 113 | */ |
| 114 | |
| 115 | const char* |
| 116 | sinc_get_name (int src_enum) |
| 117 | { |
| 118 | switch (src_enum) |
| 119 | { case SRC_SINC_BEST_QUALITY : |
| 120 | return "Best Sinc Interpolator" ; |
| 121 | |
| 122 | case SRC_SINC_MEDIUM_QUALITY : |
| 123 | return "Medium Sinc Interpolator" ; |
| 124 | |
| 125 | case SRC_SINC_FASTEST : |
| 126 | return "Fastest Sinc Interpolator" ; |
| 127 | |
| 128 | default: break ; |
| 129 | } ; |
| 130 | |
| 131 | return NULL ; |
| 132 | } /* sinc_get_descrition */ |
| 133 | |
| 134 | const char* |
| 135 | sinc_get_description (int src_enum) |
| 136 | { |
| 137 | switch (src_enum) |
| 138 | { case SRC_SINC_FASTEST : |
| 139 | return "Band limited sinc interpolation, fastest, 97dB SNR, 80% BW." ; |
| 140 | |
| 141 | case SRC_SINC_MEDIUM_QUALITY : |
| 142 | return "Band limited sinc interpolation, medium quality, 121dB SNR, 90% BW." ; |
| 143 | |
| 144 | case SRC_SINC_BEST_QUALITY : |
| 145 | return "Band limited sinc interpolation, best quality, 145dB SNR, 96% BW." ; |
| 146 | |
| 147 | default : |
| 148 | break ; |
| 149 | } ; |
| 150 | |
| 151 | return NULL ; |
| 152 | } /* sinc_get_descrition */ |
| 153 | |
| 154 | int |
| 155 | sinc_set_converter (SRC_PRIVATE *psrc, int src_enum) |
| 156 | { SINC_FILTER *filter, temp_filter ; |
| 157 | increment_t count ; |
| 158 | int bits ; |
| 159 | |
| 160 | /* Quick sanity check. */ |
| 161 | if (SHIFT_BITS >= sizeof (increment_t) * 8 - 1) |
| 162 | return SRC_ERR_SHIFT_BITS ; |
| 163 | |
| 164 | if (psrc->private_data != NULL) |
| 165 | { free (psrc->private_data) ; |
| 166 | psrc->private_data = NULL ; |
| 167 | } ; |
| 168 | |
| 169 | memset (&temp_filter, 0, sizeof (temp_filter)) ; |
| 170 | |
| 171 | temp_filter.sinc_magic_marker = SINC_MAGIC_MARKER ; |
| 172 | temp_filter.channels = psrc->channels ; |
| 173 | |
| 174 | if (psrc->channels > ARRAY_LEN (temp_filter.left_calc)) |
| 175 | return SRC_ERR_BAD_CHANNEL_COUNT ; |
| 176 | else if (psrc->channels == 1) |
| 177 | { psrc->const_process = sinc_mono_vari_process ; |
| 178 | psrc->vari_process = sinc_mono_vari_process ; |
| 179 | } |
| 180 | else |
| 181 | if (psrc->channels == 2) |
| 182 | { psrc->const_process = sinc_stereo_vari_process ; |
| 183 | psrc->vari_process = sinc_stereo_vari_process ; |
| 184 | } |
| 185 | else |
| 186 | if (psrc->channels == 4) |
| 187 | { psrc->const_process = sinc_quad_vari_process ; |
| 188 | psrc->vari_process = sinc_quad_vari_process ; |
| 189 | } |
| 190 | else |
| 191 | if (psrc->channels == 6) |
| 192 | { psrc->const_process = sinc_hex_vari_process ; |
| 193 | psrc->vari_process = sinc_hex_vari_process ; |
| 194 | } |
| 195 | else |
| 196 | { psrc->const_process = sinc_multichan_vari_process ; |
| 197 | psrc->vari_process = sinc_multichan_vari_process ; |
| 198 | } ; |
| 199 | psrc->reset = sinc_reset ; |
| 200 | |
| 201 | switch (src_enum) |
| 202 | { case SRC_SINC_FASTEST : |
| 203 | temp_filter.coeffs = fastest_coeffs.coeffs ; |
| 204 | temp_filter.coeff_half_len = ARRAY_LEN (fastest_coeffs.coeffs) - 1 ; |
| 205 | temp_filter.index_inc = fastest_coeffs.increment ; |
| 206 | break ; |
| 207 | |
| 208 | case SRC_SINC_MEDIUM_QUALITY : |
| 209 | temp_filter.coeffs = slow_mid_qual_coeffs.coeffs ; |
| 210 | temp_filter.coeff_half_len = ARRAY_LEN (slow_mid_qual_coeffs.coeffs) - 1 ; |
| 211 | temp_filter.index_inc = slow_mid_qual_coeffs.increment ; |
| 212 | break ; |
| 213 | |
| 214 | case SRC_SINC_BEST_QUALITY : |
| 215 | temp_filter.coeffs = slow_high_qual_coeffs.coeffs ; |
| 216 | temp_filter.coeff_half_len = ARRAY_LEN (slow_high_qual_coeffs.coeffs) - 1 ; |
| 217 | temp_filter.index_inc = slow_high_qual_coeffs.increment ; |
| 218 | break ; |
| 219 | |
| 220 | default : |
| 221 | return SRC_ERR_BAD_CONVERTER ; |
| 222 | } ; |
| 223 | |
| 224 | /* |
| 225 | ** FIXME : This needs to be looked at more closely to see if there is |
| 226 | ** a better way. Need to look at prepare_data () at the same time. |
| 227 | */ |
| 228 | |
| 229 | temp_filter.b_len = lrint (2.5 * temp_filter.coeff_half_len / (temp_filter.index_inc * 1.0) * SRC_MAX_RATIO) ; |
| 230 | temp_filter.b_len = MAX (temp_filter.b_len, 4096) ; |
| 231 | temp_filter.b_len *= temp_filter.channels ; |
| 232 | |
| 233 | if ((filter = calloc (1, sizeof (SINC_FILTER) + sizeof (filter->buffer [0]) * (temp_filter.b_len + temp_filter.channels))) == NULL) |
| 234 | return SRC_ERR_MALLOC_FAILED ; |
| 235 | |
| 236 | *filter = temp_filter ; |
| 237 | memset (&temp_filter, 0xEE, sizeof (temp_filter)) ; |
| 238 | |
| 239 | psrc->private_data = filter ; |
| 240 | |
| 241 | sinc_reset (psrc) ; |
| 242 | |
| 243 | count = filter->coeff_half_len ; |
| 244 | for (bits = 0 ; (MAKE_INCREMENT_T (1) << bits) < count ; bits++) |
| 245 | count |= (MAKE_INCREMENT_T (1) << bits) ; |
| 246 | |
| 247 | if (bits + SHIFT_BITS - 1 >= (int) (sizeof (increment_t) * 8)) |
| 248 | return SRC_ERR_FILTER_LEN ; |
| 249 | |
| 250 | return SRC_ERR_NO_ERROR ; |
| 251 | } /* sinc_set_converter */ |
| 252 | |
| 253 | static void |
| 254 | sinc_reset (SRC_PRIVATE *psrc) |
| 255 | { SINC_FILTER *filter ; |
| 256 | |
| 257 | filter = (SINC_FILTER*) psrc->private_data ; |
| 258 | if (filter == NULL) |
| 259 | return ; |
| 260 | |
| 261 | filter->b_current = filter->b_end = 0 ; |
| 262 | filter->b_real_end = -1 ; |
| 263 | |
| 264 | filter->src_ratio = filter->input_index = 0.0 ; |
| 265 | |
| 266 | memset (filter->buffer, 0, filter->b_len * sizeof (filter->buffer [0])) ; |
| 267 | |
| 268 | /* Set this for a sanity check */ |
| 269 | memset (filter->buffer + filter->b_len, 0xAA, filter->channels * sizeof (filter->buffer [0])) ; |
| 270 | } /* sinc_reset */ |
| 271 | |
| 272 | /*======================================================================================== |
| 273 | ** Beware all ye who dare pass this point. There be dragons here. |
| 274 | */ |
| 275 | |
| 276 | static inline double |
| 277 | calc_output_single (SINC_FILTER *filter, increment_t increment, increment_t start_filter_index) |
| 278 | { double fraction, left, right, icoeff ; |
| 279 | increment_t filter_index, max_filter_index ; |
| 280 | int data_index, coeff_count, indx ; |
| 281 | |
| 282 | /* Convert input parameters into fixed point. */ |
| 283 | max_filter_index = int_to_fp (filter->coeff_half_len) ; |
| 284 | |
| 285 | /* First apply the left half of the filter. */ |
| 286 | filter_index = start_filter_index ; |
| 287 | coeff_count = (max_filter_index - filter_index) / increment ; |
| 288 | filter_index = filter_index + coeff_count * increment ; |
| 289 | data_index = filter->b_current - coeff_count ; |
| 290 | |
| 291 | left = 0.0 ; |
| 292 | do |
| 293 | { fraction = fp_to_double (filter_index) ; |
| 294 | indx = fp_to_int (filter_index) ; |
| 295 | |
| 296 | icoeff = filter->coeffs [indx] + fraction * (filter->coeffs [indx + 1] - filter->coeffs [indx]) ; |
| 297 | |
| 298 | left += icoeff * filter->buffer [data_index] ; |
| 299 | |
| 300 | filter_index -= increment ; |
| 301 | data_index = data_index + 1 ; |
| 302 | } |
| 303 | while (filter_index >= MAKE_INCREMENT_T (0)) ; |
| 304 | |
| 305 | /* Now apply the right half of the filter. */ |
| 306 | filter_index = increment - start_filter_index ; |
| 307 | coeff_count = (max_filter_index - filter_index) / increment ; |
| 308 | filter_index = filter_index + coeff_count * increment ; |
| 309 | data_index = filter->b_current + 1 + coeff_count ; |
| 310 | |
| 311 | right = 0.0 ; |
| 312 | do |
| 313 | { fraction = fp_to_double (filter_index) ; |
| 314 | indx = fp_to_int (filter_index) ; |
| 315 | |
| 316 | icoeff = filter->coeffs [indx] + fraction * (filter->coeffs [indx + 1] - filter->coeffs [indx]) ; |
| 317 | |
| 318 | right += icoeff * filter->buffer [data_index] ; |
| 319 | |
| 320 | filter_index -= increment ; |
| 321 | data_index = data_index - 1 ; |
| 322 | } |
| 323 | while (filter_index > MAKE_INCREMENT_T (0)) ; |
| 324 | |
| 325 | return (left + right) ; |
| 326 | } /* calc_output_single */ |
| 327 | |
| 328 | static int |
| 329 | sinc_mono_vari_process (SRC_PRIVATE *psrc, SRC_DATA *data) |
| 330 | { SINC_FILTER *filter ; |
| 331 | double input_index, src_ratio, count, float_increment, terminate, rem ; |
| 332 | increment_t increment, start_filter_index ; |
| 333 | int half_filter_chan_len, samples_in_hand ; |
| 334 | |
| 335 | if (psrc->private_data == NULL) |
| 336 | return SRC_ERR_NO_PRIVATE ; |
| 337 | |
| 338 | filter = (SINC_FILTER*) psrc->private_data ; |
| 339 | |
| 340 | /* If there is not a problem, this will be optimised out. */ |
| 341 | if (sizeof (filter->buffer [0]) != sizeof (data->data_in [0])) |
| 342 | return SRC_ERR_SIZE_INCOMPATIBILITY ; |
| 343 | |
| 344 | filter->in_count = data->input_frames * filter->channels ; |
| 345 | filter->out_count = data->output_frames * filter->channels ; |
| 346 | filter->in_used = filter->out_gen = 0 ; |
| 347 | |
| 348 | src_ratio = psrc->last_ratio ; |
| 349 | |
| 350 | /* Check the sample rate ratio wrt the buffer len. */ |
| 351 | count = (filter->coeff_half_len + 2.0) / filter->index_inc ; |
| 352 | if (MIN (psrc->last_ratio, data->src_ratio) < 1.0) |
| 353 | count /= MIN (psrc->last_ratio, data->src_ratio) ; |
| 354 | |
| 355 | /* Maximum coefficientson either side of center point. */ |
| 356 | half_filter_chan_len = filter->channels * (lrint (count) + 1) ; |
| 357 | |
| 358 | input_index = psrc->last_position ; |
| 359 | float_increment = filter->index_inc ; |
| 360 | |
| 361 | rem = fmod_one (input_index) ; |
| 362 | filter->b_current = (filter->b_current + filter->channels * lrint (input_index - rem)) % filter->b_len ; |
| 363 | input_index = rem ; |
| 364 | |
| 365 | terminate = 1.0 / src_ratio + 1e-20 ; |
| 366 | |
| 367 | /* Main processing loop. */ |
| 368 | while (filter->out_gen < filter->out_count) |
| 369 | { |
| 370 | /* Need to reload buffer? */ |
| 371 | samples_in_hand = (filter->b_end - filter->b_current + filter->b_len) % filter->b_len ; |
| 372 | |
| 373 | if (samples_in_hand <= half_filter_chan_len) |
| 374 | { if ((psrc->error = prepare_data (filter, data, half_filter_chan_len)) != 0) |
| 375 | return psrc->error ; |
| 376 | |
| 377 | samples_in_hand = (filter->b_end - filter->b_current + filter->b_len) % filter->b_len ; |
| 378 | if (samples_in_hand <= half_filter_chan_len) |
| 379 | break ; |
| 380 | } ; |
| 381 | |
| 382 | /* This is the termination condition. */ |
| 383 | if (filter->b_real_end >= 0) |
| 384 | { if (filter->b_current + input_index + terminate >= filter->b_real_end) |
| 385 | break ; |
| 386 | } ; |
| 387 | |
| 388 | if (filter->out_count > 0 && fabs (psrc->last_ratio - data->src_ratio) > 1e-10) |
| 389 | src_ratio = psrc->last_ratio + filter->out_gen * (data->src_ratio - psrc->last_ratio) / filter->out_count ; |
| 390 | |
| 391 | float_increment = filter->index_inc * 1.0 ; |
| 392 | if (src_ratio < 1.0) |
| 393 | float_increment = filter->index_inc * src_ratio ; |
| 394 | |
| 395 | increment = double_to_fp (float_increment) ; |
| 396 | |
| 397 | start_filter_index = double_to_fp (input_index * float_increment) ; |
| 398 | |
| 399 | data->data_out [filter->out_gen] = (float) ((float_increment / filter->index_inc) * |
| 400 | calc_output_single (filter, increment, start_filter_index)) ; |
| 401 | filter->out_gen ++ ; |
| 402 | |
| 403 | /* Figure out the next index. */ |
| 404 | input_index += 1.0 / src_ratio ; |
| 405 | rem = fmod_one (input_index) ; |
| 406 | |
| 407 | filter->b_current = (filter->b_current + filter->channels * lrint (input_index - rem)) % filter->b_len ; |
| 408 | input_index = rem ; |
| 409 | } ; |
| 410 | |
| 411 | psrc->last_position = input_index ; |
| 412 | |
| 413 | /* Save current ratio rather then target ratio. */ |
| 414 | psrc->last_ratio = src_ratio ; |
| 415 | |
| 416 | data->input_frames_used = filter->in_used / filter->channels ; |
| 417 | data->output_frames_gen = filter->out_gen / filter->channels ; |
| 418 | |
| 419 | return SRC_ERR_NO_ERROR ; |
| 420 | } /* sinc_mono_vari_process */ |
| 421 | |
| 422 | static inline void |
| 423 | calc_output_stereo (SINC_FILTER *filter, increment_t increment, increment_t start_filter_index, double scale, float * output) |
| 424 | { double fraction, left [2], right [2], icoeff ; |
| 425 | increment_t filter_index, max_filter_index ; |
| 426 | int data_index, coeff_count, indx ; |
| 427 | |
| 428 | /* Convert input parameters into fixed point. */ |
| 429 | max_filter_index = int_to_fp (filter->coeff_half_len) ; |
| 430 | |
| 431 | /* First apply the left half of the filter. */ |
| 432 | filter_index = start_filter_index ; |
| 433 | coeff_count = (max_filter_index - filter_index) / increment ; |
| 434 | filter_index = filter_index + coeff_count * increment ; |
| 435 | data_index = filter->b_current - filter->channels * coeff_count ; |
| 436 | |
| 437 | left [0] = left [1] = 0.0 ; |
| 438 | do |
| 439 | { fraction = fp_to_double (filter_index) ; |
| 440 | indx = fp_to_int (filter_index) ; |
| 441 | |
| 442 | icoeff = filter->coeffs [indx] + fraction * (filter->coeffs [indx + 1] - filter->coeffs [indx]) ; |
| 443 | |
| 444 | left [0] += icoeff * filter->buffer [data_index] ; |
| 445 | left [1] += icoeff * filter->buffer [data_index + 1] ; |
| 446 | |
| 447 | filter_index -= increment ; |
| 448 | data_index = data_index + 2 ; |
| 449 | } |
| 450 | while (filter_index >= MAKE_INCREMENT_T (0)) ; |
| 451 | |
| 452 | /* Now apply the right half of the filter. */ |
| 453 | filter_index = increment - start_filter_index ; |
| 454 | coeff_count = (max_filter_index - filter_index) / increment ; |
| 455 | filter_index = filter_index + coeff_count * increment ; |
| 456 | data_index = filter->b_current + filter->channels * (1 + coeff_count) ; |
| 457 | |
| 458 | right [0] = right [1] = 0.0 ; |
| 459 | do |
| 460 | { fraction = fp_to_double (filter_index) ; |
| 461 | indx = fp_to_int (filter_index) ; |
| 462 | |
| 463 | icoeff = filter->coeffs [indx] + fraction * (filter->coeffs [indx + 1] - filter->coeffs [indx]) ; |
| 464 | |
| 465 | right [0] += icoeff * filter->buffer [data_index] ; |
| 466 | right [1] += icoeff * filter->buffer [data_index + 1] ; |
| 467 | |
| 468 | filter_index -= increment ; |
| 469 | data_index = data_index - 2 ; |
| 470 | } |
| 471 | while (filter_index > MAKE_INCREMENT_T (0)) ; |
| 472 | |
| 473 | output [0] = scale * (left [0] + right [0]) ; |
| 474 | output [1] = scale * (left [1] + right [1]) ; |
| 475 | } /* calc_output_stereo */ |
| 476 | |
| 477 | static int |
| 478 | sinc_stereo_vari_process (SRC_PRIVATE *psrc, SRC_DATA *data) |
| 479 | { SINC_FILTER *filter ; |
| 480 | double input_index, src_ratio, count, float_increment, terminate, rem ; |
| 481 | increment_t increment, start_filter_index ; |
| 482 | int half_filter_chan_len, samples_in_hand ; |
| 483 | |
| 484 | if (psrc->private_data == NULL) |
| 485 | return SRC_ERR_NO_PRIVATE ; |
| 486 | |
| 487 | filter = (SINC_FILTER*) psrc->private_data ; |
| 488 | |
| 489 | /* If there is not a problem, this will be optimised out. */ |
| 490 | if (sizeof (filter->buffer [0]) != sizeof (data->data_in [0])) |
| 491 | return SRC_ERR_SIZE_INCOMPATIBILITY ; |
| 492 | |
| 493 | filter->in_count = data->input_frames * filter->channels ; |
| 494 | filter->out_count = data->output_frames * filter->channels ; |
| 495 | filter->in_used = filter->out_gen = 0 ; |
| 496 | |
| 497 | src_ratio = psrc->last_ratio ; |
| 498 | |
| 499 | /* Check the sample rate ratio wrt the buffer len. */ |
| 500 | count = (filter->coeff_half_len + 2.0) / filter->index_inc ; |
| 501 | if (MIN (psrc->last_ratio, data->src_ratio) < 1.0) |
| 502 | count /= MIN (psrc->last_ratio, data->src_ratio) ; |
| 503 | |
| 504 | /* Maximum coefficientson either side of center point. */ |
| 505 | half_filter_chan_len = filter->channels * (lrint (count) + 1) ; |
| 506 | |
| 507 | input_index = psrc->last_position ; |
| 508 | float_increment = filter->index_inc ; |
| 509 | |
| 510 | rem = fmod_one (input_index) ; |
| 511 | filter->b_current = (filter->b_current + filter->channels * lrint (input_index - rem)) % filter->b_len ; |
| 512 | input_index = rem ; |
| 513 | |
| 514 | terminate = 1.0 / src_ratio + 1e-20 ; |
| 515 | |
| 516 | /* Main processing loop. */ |
| 517 | while (filter->out_gen < filter->out_count) |
| 518 | { |
| 519 | /* Need to reload buffer? */ |
| 520 | samples_in_hand = (filter->b_end - filter->b_current + filter->b_len) % filter->b_len ; |
| 521 | |
| 522 | if (samples_in_hand <= half_filter_chan_len) |
| 523 | { if ((psrc->error = prepare_data (filter, data, half_filter_chan_len)) != 0) |
| 524 | return psrc->error ; |
| 525 | |
| 526 | samples_in_hand = (filter->b_end - filter->b_current + filter->b_len) % filter->b_len ; |
| 527 | if (samples_in_hand <= half_filter_chan_len) |
| 528 | break ; |
| 529 | } ; |
| 530 | |
| 531 | /* This is the termination condition. */ |
| 532 | if (filter->b_real_end >= 0) |
| 533 | { if (filter->b_current + input_index + terminate >= filter->b_real_end) |
| 534 | break ; |
| 535 | } ; |
| 536 | |
| 537 | if (filter->out_count > 0 && fabs (psrc->last_ratio - data->src_ratio) > 1e-10) |
| 538 | src_ratio = psrc->last_ratio + filter->out_gen * (data->src_ratio - psrc->last_ratio) / filter->out_count ; |
| 539 | |
| 540 | float_increment = filter->index_inc * 1.0 ; |
| 541 | if (src_ratio < 1.0) |
| 542 | float_increment = filter->index_inc * src_ratio ; |
| 543 | |
| 544 | increment = double_to_fp (float_increment) ; |
| 545 | |
| 546 | start_filter_index = double_to_fp (input_index * float_increment) ; |
| 547 | |
| 548 | calc_output_stereo (filter, increment, start_filter_index, float_increment / filter->index_inc, data->data_out + filter->out_gen) ; |
| 549 | filter->out_gen += 2 ; |
| 550 | |
| 551 | /* Figure out the next index. */ |
| 552 | input_index += 1.0 / src_ratio ; |
| 553 | rem = fmod_one (input_index) ; |
| 554 | |
| 555 | filter->b_current = (filter->b_current + filter->channels * lrint (input_index - rem)) % filter->b_len ; |
| 556 | input_index = rem ; |
| 557 | } ; |
| 558 | |
| 559 | psrc->last_position = input_index ; |
| 560 | |
| 561 | /* Save current ratio rather then target ratio. */ |
| 562 | psrc->last_ratio = src_ratio ; |
| 563 | |
| 564 | data->input_frames_used = filter->in_used / filter->channels ; |
| 565 | data->output_frames_gen = filter->out_gen / filter->channels ; |
| 566 | |
| 567 | return SRC_ERR_NO_ERROR ; |
| 568 | } /* sinc_stereo_vari_process */ |
| 569 | |
| 570 | static inline void |
| 571 | calc_output_quad (SINC_FILTER *filter, increment_t increment, increment_t start_filter_index, double scale, float * output) |
| 572 | { double fraction, left [4], right [4], icoeff ; |
| 573 | increment_t filter_index, max_filter_index ; |
| 574 | int data_index, coeff_count, indx ; |
| 575 | |
| 576 | /* Convert input parameters into fixed point. */ |
| 577 | max_filter_index = int_to_fp (filter->coeff_half_len) ; |
| 578 | |
| 579 | /* First apply the left half of the filter. */ |
| 580 | filter_index = start_filter_index ; |
| 581 | coeff_count = (max_filter_index - filter_index) / increment ; |
| 582 | filter_index = filter_index + coeff_count * increment ; |
| 583 | data_index = filter->b_current - filter->channels * coeff_count ; |
| 584 | |
| 585 | left [0] = left [1] = left [2] = left [3] = 0.0 ; |
| 586 | do |
| 587 | { fraction = fp_to_double (filter_index) ; |
| 588 | indx = fp_to_int (filter_index) ; |
| 589 | |
| 590 | icoeff = filter->coeffs [indx] + fraction * (filter->coeffs [indx + 1] - filter->coeffs [indx]) ; |
| 591 | |
| 592 | left [0] += icoeff * filter->buffer [data_index] ; |
| 593 | left [1] += icoeff * filter->buffer [data_index + 1] ; |
| 594 | left [2] += icoeff * filter->buffer [data_index + 2] ; |
| 595 | left [3] += icoeff * filter->buffer [data_index + 3] ; |
| 596 | |
| 597 | filter_index -= increment ; |
| 598 | data_index = data_index + 4 ; |
| 599 | } |
| 600 | while (filter_index >= MAKE_INCREMENT_T (0)) ; |
| 601 | |
| 602 | /* Now apply the right half of the filter. */ |
| 603 | filter_index = increment - start_filter_index ; |
| 604 | coeff_count = (max_filter_index - filter_index) / increment ; |
| 605 | filter_index = filter_index + coeff_count * increment ; |
| 606 | data_index = filter->b_current + filter->channels * (1 + coeff_count) ; |
| 607 | |
| 608 | right [0] = right [1] = right [2] = right [3] = 0.0 ; |
| 609 | do |
| 610 | { fraction = fp_to_double (filter_index) ; |
| 611 | indx = fp_to_int (filter_index) ; |
| 612 | |
| 613 | icoeff = filter->coeffs [indx] + fraction * (filter->coeffs [indx + 1] - filter->coeffs [indx]) ; |
| 614 | |
| 615 | right [0] += icoeff * filter->buffer [data_index] ; |
| 616 | right [1] += icoeff * filter->buffer [data_index + 1] ; |
| 617 | right [2] += icoeff * filter->buffer [data_index + 2] ; |
| 618 | right [3] += icoeff * filter->buffer [data_index + 3] ; |
| 619 | |
| 620 | filter_index -= increment ; |
| 621 | data_index = data_index - 4 ; |
| 622 | } |
| 623 | while (filter_index > MAKE_INCREMENT_T (0)) ; |
| 624 | |
| 625 | output [0] = scale * (left [0] + right [0]) ; |
| 626 | output [1] = scale * (left [1] + right [1]) ; |
| 627 | output [2] = scale * (left [2] + right [2]) ; |
| 628 | output [3] = scale * (left [3] + right [3]) ; |
| 629 | } /* calc_output_quad */ |
| 630 | |
| 631 | static int |
| 632 | sinc_quad_vari_process (SRC_PRIVATE *psrc, SRC_DATA *data) |
| 633 | { SINC_FILTER *filter ; |
| 634 | double input_index, src_ratio, count, float_increment, terminate, rem ; |
| 635 | increment_t increment, start_filter_index ; |
| 636 | int half_filter_chan_len, samples_in_hand ; |
| 637 | |
| 638 | if (psrc->private_data == NULL) |
| 639 | return SRC_ERR_NO_PRIVATE ; |
| 640 | |
| 641 | filter = (SINC_FILTER*) psrc->private_data ; |
| 642 | |
| 643 | /* If there is not a problem, this will be optimised out. */ |
| 644 | if (sizeof (filter->buffer [0]) != sizeof (data->data_in [0])) |
| 645 | return SRC_ERR_SIZE_INCOMPATIBILITY ; |
| 646 | |
| 647 | filter->in_count = data->input_frames * filter->channels ; |
| 648 | filter->out_count = data->output_frames * filter->channels ; |
| 649 | filter->in_used = filter->out_gen = 0 ; |
| 650 | |
| 651 | src_ratio = psrc->last_ratio ; |
| 652 | |
| 653 | /* Check the sample rate ratio wrt the buffer len. */ |
| 654 | count = (filter->coeff_half_len + 2.0) / filter->index_inc ; |
| 655 | if (MIN (psrc->last_ratio, data->src_ratio) < 1.0) |
| 656 | count /= MIN (psrc->last_ratio, data->src_ratio) ; |
| 657 | |
| 658 | /* Maximum coefficientson either side of center point. */ |
| 659 | half_filter_chan_len = filter->channels * (lrint (count) + 1) ; |
| 660 | |
| 661 | input_index = psrc->last_position ; |
| 662 | float_increment = filter->index_inc ; |
| 663 | |
| 664 | rem = fmod_one (input_index) ; |
| 665 | filter->b_current = (filter->b_current + filter->channels * lrint (input_index - rem)) % filter->b_len ; |
| 666 | input_index = rem ; |
| 667 | |
| 668 | terminate = 1.0 / src_ratio + 1e-20 ; |
| 669 | |
| 670 | /* Main processing loop. */ |
| 671 | while (filter->out_gen < filter->out_count) |
| 672 | { |
| 673 | /* Need to reload buffer? */ |
| 674 | samples_in_hand = (filter->b_end - filter->b_current + filter->b_len) % filter->b_len ; |
| 675 | |
| 676 | if (samples_in_hand <= half_filter_chan_len) |
| 677 | { if ((psrc->error = prepare_data (filter, data, half_filter_chan_len)) != 0) |
| 678 | return psrc->error ; |
| 679 | |
| 680 | samples_in_hand = (filter->b_end - filter->b_current + filter->b_len) % filter->b_len ; |
| 681 | if (samples_in_hand <= half_filter_chan_len) |
| 682 | break ; |
| 683 | } ; |
| 684 | |
| 685 | /* This is the termination condition. */ |
| 686 | if (filter->b_real_end >= 0) |
| 687 | { if (filter->b_current + input_index + terminate >= filter->b_real_end) |
| 688 | break ; |
| 689 | } ; |
| 690 | |
| 691 | if (filter->out_count > 0 && fabs (psrc->last_ratio - data->src_ratio) > 1e-10) |
| 692 | src_ratio = psrc->last_ratio + filter->out_gen * (data->src_ratio - psrc->last_ratio) / filter->out_count ; |
| 693 | |
| 694 | float_increment = filter->index_inc * 1.0 ; |
| 695 | if (src_ratio < 1.0) |
| 696 | float_increment = filter->index_inc * src_ratio ; |
| 697 | |
| 698 | increment = double_to_fp (float_increment) ; |
| 699 | |
| 700 | start_filter_index = double_to_fp (input_index * float_increment) ; |
| 701 | |
| 702 | calc_output_quad (filter, increment, start_filter_index, float_increment / filter->index_inc, data->data_out + filter->out_gen) ; |
| 703 | filter->out_gen += 4 ; |
| 704 | |
| 705 | /* Figure out the next index. */ |
| 706 | input_index += 1.0 / src_ratio ; |
| 707 | rem = fmod_one (input_index) ; |
| 708 | |
| 709 | filter->b_current = (filter->b_current + filter->channels * lrint (input_index - rem)) % filter->b_len ; |
| 710 | input_index = rem ; |
| 711 | } ; |
| 712 | |
| 713 | psrc->last_position = input_index ; |
| 714 | |
| 715 | /* Save current ratio rather then target ratio. */ |
| 716 | psrc->last_ratio = src_ratio ; |
| 717 | |
| 718 | data->input_frames_used = filter->in_used / filter->channels ; |
| 719 | data->output_frames_gen = filter->out_gen / filter->channels ; |
| 720 | |
| 721 | return SRC_ERR_NO_ERROR ; |
| 722 | } /* sinc_quad_vari_process */ |
| 723 | |
| 724 | static inline void |
| 725 | calc_output_hex (SINC_FILTER *filter, increment_t increment, increment_t start_filter_index, double scale, float * output) |
| 726 | { double fraction, left [6], right [6], icoeff ; |
| 727 | increment_t filter_index, max_filter_index ; |
| 728 | int data_index, coeff_count, indx ; |
| 729 | |
| 730 | /* Convert input parameters into fixed point. */ |
| 731 | max_filter_index = int_to_fp (filter->coeff_half_len) ; |
| 732 | |
| 733 | /* First apply the left half of the filter. */ |
| 734 | filter_index = start_filter_index ; |
| 735 | coeff_count = (max_filter_index - filter_index) / increment ; |
| 736 | filter_index = filter_index + coeff_count * increment ; |
| 737 | data_index = filter->b_current - filter->channels * coeff_count ; |
| 738 | |
| 739 | left [0] = left [1] = left [2] = left [3] = left [4] = left [5] = 0.0 ; |
| 740 | do |
| 741 | { fraction = fp_to_double (filter_index) ; |
| 742 | indx = fp_to_int (filter_index) ; |
| 743 | |
| 744 | icoeff = filter->coeffs [indx] + fraction * (filter->coeffs [indx + 1] - filter->coeffs [indx]) ; |
| 745 | |
| 746 | left [0] += icoeff * filter->buffer [data_index] ; |
| 747 | left [1] += icoeff * filter->buffer [data_index + 1] ; |
| 748 | left [2] += icoeff * filter->buffer [data_index + 2] ; |
| 749 | left [3] += icoeff * filter->buffer [data_index + 3] ; |
| 750 | left [4] += icoeff * filter->buffer [data_index + 4] ; |
| 751 | left [5] += icoeff * filter->buffer [data_index + 5] ; |
| 752 | |
| 753 | filter_index -= increment ; |
| 754 | data_index = data_index + 6 ; |
| 755 | } |
| 756 | while (filter_index >= MAKE_INCREMENT_T (0)) ; |
| 757 | |
| 758 | /* Now apply the right half of the filter. */ |
| 759 | filter_index = increment - start_filter_index ; |
| 760 | coeff_count = (max_filter_index - filter_index) / increment ; |
| 761 | filter_index = filter_index + coeff_count * increment ; |
| 762 | data_index = filter->b_current + filter->channels * (1 + coeff_count) ; |
| 763 | |
| 764 | right [0] = right [1] = right [2] = right [3] = right [4] = right [5] = 0.0 ; |
| 765 | do |
| 766 | { fraction = fp_to_double (filter_index) ; |
| 767 | indx = fp_to_int (filter_index) ; |
| 768 | |
| 769 | icoeff = filter->coeffs [indx] + fraction * (filter->coeffs [indx + 1] - filter->coeffs [indx]) ; |
| 770 | |
| 771 | right [0] += icoeff * filter->buffer [data_index] ; |
| 772 | right [1] += icoeff * filter->buffer [data_index + 1] ; |
| 773 | right [2] += icoeff * filter->buffer [data_index + 2] ; |
| 774 | right [3] += icoeff * filter->buffer [data_index + 3] ; |
| 775 | right [4] += icoeff * filter->buffer [data_index + 4] ; |
| 776 | right [5] += icoeff * filter->buffer [data_index + 5] ; |
| 777 | |
| 778 | filter_index -= increment ; |
| 779 | data_index = data_index - 6 ; |
| 780 | } |
| 781 | while (filter_index > MAKE_INCREMENT_T (0)) ; |
| 782 | |
| 783 | output [0] = scale * (left [0] + right [0]) ; |
| 784 | output [1] = scale * (left [1] + right [1]) ; |
| 785 | output [2] = scale * (left [2] + right [2]) ; |
| 786 | output [3] = scale * (left [3] + right [3]) ; |
| 787 | output [4] = scale * (left [4] + right [4]) ; |
| 788 | output [5] = scale * (left [5] + right [5]) ; |
| 789 | } /* calc_output_hex */ |
| 790 | |
| 791 | static int |
| 792 | sinc_hex_vari_process (SRC_PRIVATE *psrc, SRC_DATA *data) |
| 793 | { SINC_FILTER *filter ; |
| 794 | double input_index, src_ratio, count, float_increment, terminate, rem ; |
| 795 | increment_t increment, start_filter_index ; |
| 796 | int half_filter_chan_len, samples_in_hand ; |
| 797 | |
| 798 | if (psrc->private_data == NULL) |
| 799 | return SRC_ERR_NO_PRIVATE ; |
| 800 | |
| 801 | filter = (SINC_FILTER*) psrc->private_data ; |
| 802 | |
| 803 | /* If there is not a problem, this will be optimised out. */ |
| 804 | if (sizeof (filter->buffer [0]) != sizeof (data->data_in [0])) |
| 805 | return SRC_ERR_SIZE_INCOMPATIBILITY ; |
| 806 | |
| 807 | filter->in_count = data->input_frames * filter->channels ; |
| 808 | filter->out_count = data->output_frames * filter->channels ; |
| 809 | filter->in_used = filter->out_gen = 0 ; |
| 810 | |
| 811 | src_ratio = psrc->last_ratio ; |
| 812 | |
| 813 | /* Check the sample rate ratio wrt the buffer len. */ |
| 814 | count = (filter->coeff_half_len + 2.0) / filter->index_inc ; |
| 815 | if (MIN (psrc->last_ratio, data->src_ratio) < 1.0) |
| 816 | count /= MIN (psrc->last_ratio, data->src_ratio) ; |
| 817 | |
| 818 | /* Maximum coefficientson either side of center point. */ |
| 819 | half_filter_chan_len = filter->channels * (lrint (count) + 1) ; |
| 820 | |
| 821 | input_index = psrc->last_position ; |
| 822 | float_increment = filter->index_inc ; |
| 823 | |
| 824 | rem = fmod_one (input_index) ; |
| 825 | filter->b_current = (filter->b_current + filter->channels * lrint (input_index - rem)) % filter->b_len ; |
| 826 | input_index = rem ; |
| 827 | |
| 828 | terminate = 1.0 / src_ratio + 1e-20 ; |
| 829 | |
| 830 | /* Main processing loop. */ |
| 831 | while (filter->out_gen < filter->out_count) |
| 832 | { |
| 833 | /* Need to reload buffer? */ |
| 834 | samples_in_hand = (filter->b_end - filter->b_current + filter->b_len) % filter->b_len ; |
| 835 | |
| 836 | if (samples_in_hand <= half_filter_chan_len) |
| 837 | { if ((psrc->error = prepare_data (filter, data, half_filter_chan_len)) != 0) |
| 838 | return psrc->error ; |
| 839 | |
| 840 | samples_in_hand = (filter->b_end - filter->b_current + filter->b_len) % filter->b_len ; |
| 841 | if (samples_in_hand <= half_filter_chan_len) |
| 842 | break ; |
| 843 | } ; |
| 844 | |
| 845 | /* This is the termination condition. */ |
| 846 | if (filter->b_real_end >= 0) |
| 847 | { if (filter->b_current + input_index + terminate >= filter->b_real_end) |
| 848 | break ; |
| 849 | } ; |
| 850 | |
| 851 | if (filter->out_count > 0 && fabs (psrc->last_ratio - data->src_ratio) > 1e-10) |
| 852 | src_ratio = psrc->last_ratio + filter->out_gen * (data->src_ratio - psrc->last_ratio) / filter->out_count ; |
| 853 | |
| 854 | float_increment = filter->index_inc * 1.0 ; |
| 855 | if (src_ratio < 1.0) |
| 856 | float_increment = filter->index_inc * src_ratio ; |
| 857 | |
| 858 | increment = double_to_fp (float_increment) ; |
| 859 | |
| 860 | start_filter_index = double_to_fp (input_index * float_increment) ; |
| 861 | |
| 862 | calc_output_hex (filter, increment, start_filter_index, float_increment / filter->index_inc, data->data_out + filter->out_gen) ; |
| 863 | filter->out_gen += 6 ; |
| 864 | |
| 865 | /* Figure out the next index. */ |
| 866 | input_index += 1.0 / src_ratio ; |
| 867 | rem = fmod_one (input_index) ; |
| 868 | |
| 869 | filter->b_current = (filter->b_current + filter->channels * lrint (input_index - rem)) % filter->b_len ; |
| 870 | input_index = rem ; |
| 871 | } ; |
| 872 | |
| 873 | psrc->last_position = input_index ; |
| 874 | |
| 875 | /* Save current ratio rather then target ratio. */ |
| 876 | psrc->last_ratio = src_ratio ; |
| 877 | |
| 878 | data->input_frames_used = filter->in_used / filter->channels ; |
| 879 | data->output_frames_gen = filter->out_gen / filter->channels ; |
| 880 | |
| 881 | return SRC_ERR_NO_ERROR ; |
| 882 | } /* sinc_hex_vari_process */ |
| 883 | |
| 884 | static inline void |
| 885 | calc_output_multi (SINC_FILTER *filter, increment_t increment, increment_t start_filter_index, int channels, double scale, float * output) |
| 886 | { double fraction, icoeff ; |
| 887 | /* The following line is 1999 ISO Standard C. If your compiler complains, get a better compiler. */ |
| 888 | double *left, *right ; |
| 889 | increment_t filter_index, max_filter_index ; |
| 890 | int data_index, coeff_count, indx, ch ; |
| 891 | |
| 892 | left = filter->left_calc ; |
| 893 | right = filter->right_calc ; |
| 894 | |
| 895 | /* Convert input parameters into fixed point. */ |
| 896 | max_filter_index = int_to_fp (filter->coeff_half_len) ; |
| 897 | |
| 898 | /* First apply the left half of the filter. */ |
| 899 | filter_index = start_filter_index ; |
| 900 | coeff_count = (max_filter_index - filter_index) / increment ; |
| 901 | filter_index = filter_index + coeff_count * increment ; |
| 902 | data_index = filter->b_current - channels * coeff_count ; |
| 903 | |
| 904 | memset (left, 0, sizeof (left [0]) * channels) ; |
| 905 | |
| 906 | do |
| 907 | { fraction = fp_to_double (filter_index) ; |
| 908 | indx = fp_to_int (filter_index) ; |
| 909 | |
| 910 | icoeff = filter->coeffs [indx] + fraction * (filter->coeffs [indx + 1] - filter->coeffs [indx]) ; |
| 911 | |
| 912 | /* |
| 913 | ** Duff's Device. |
| 914 | ** See : http://en.wikipedia.org/wiki/Duff's_device |
| 915 | */ |
| 916 | ch = channels ; |
| 917 | do |
| 918 | { |
| 919 | switch (ch % 8) |
| 920 | { default : |
| 921 | ch -- ; |
| 922 | left [ch] += icoeff * filter->buffer [data_index + ch] ; |
| 923 | case 7 : |
| 924 | ch -- ; |
| 925 | left [ch] += icoeff * filter->buffer [data_index + ch] ; |
| 926 | case 6 : |
| 927 | ch -- ; |
| 928 | left [ch] += icoeff * filter->buffer [data_index + ch] ; |
| 929 | case 5 : |
| 930 | ch -- ; |
| 931 | left [ch] += icoeff * filter->buffer [data_index + ch] ; |
| 932 | case 4 : |
| 933 | ch -- ; |
| 934 | left [ch] += icoeff * filter->buffer [data_index + ch] ; |
| 935 | case 3 : |
| 936 | ch -- ; |
| 937 | left [ch] += icoeff * filter->buffer [data_index + ch] ; |
| 938 | case 2 : |
| 939 | ch -- ; |
| 940 | left [ch] += icoeff * filter->buffer [data_index + ch] ; |
| 941 | case 1 : |
| 942 | ch -- ; |
| 943 | left [ch] += icoeff * filter->buffer [data_index + ch] ; |
| 944 | } ; |
| 945 | } |
| 946 | while (ch > 0) ; |
| 947 | |
| 948 | filter_index -= increment ; |
| 949 | data_index = data_index + channels ; |
| 950 | } |
| 951 | while (filter_index >= MAKE_INCREMENT_T (0)) ; |
| 952 | |
| 953 | /* Now apply the right half of the filter. */ |
| 954 | filter_index = increment - start_filter_index ; |
| 955 | coeff_count = (max_filter_index - filter_index) / increment ; |
| 956 | filter_index = filter_index + coeff_count * increment ; |
| 957 | data_index = filter->b_current + channels * (1 + coeff_count) ; |
| 958 | |
| 959 | memset (right, 0, sizeof (right [0]) * channels) ; |
| 960 | do |
| 961 | { fraction = fp_to_double (filter_index) ; |
| 962 | indx = fp_to_int (filter_index) ; |
| 963 | |
| 964 | icoeff = filter->coeffs [indx] + fraction * (filter->coeffs [indx + 1] - filter->coeffs [indx]) ; |
| 965 | |
| 966 | ch = channels ; |
| 967 | do |
| 968 | { |
| 969 | switch (ch % 8) |
| 970 | { default : |
| 971 | ch -- ; |
| 972 | right [ch] += icoeff * filter->buffer [data_index + ch] ; |
| 973 | case 7 : |
| 974 | ch -- ; |
| 975 | right [ch] += icoeff * filter->buffer [data_index + ch] ; |
| 976 | case 6 : |
| 977 | ch -- ; |
| 978 | right [ch] += icoeff * filter->buffer [data_index + ch] ; |
| 979 | case 5 : |
| 980 | ch -- ; |
| 981 | right [ch] += icoeff * filter->buffer [data_index + ch] ; |
| 982 | case 4 : |
| 983 | ch -- ; |
| 984 | right [ch] += icoeff * filter->buffer [data_index + ch] ; |
| 985 | case 3 : |
| 986 | ch -- ; |
| 987 | right [ch] += icoeff * filter->buffer [data_index + ch] ; |
| 988 | case 2 : |
| 989 | ch -- ; |
| 990 | right [ch] += icoeff * filter->buffer [data_index + ch] ; |
| 991 | case 1 : |
| 992 | ch -- ; |
| 993 | right [ch] += icoeff * filter->buffer [data_index + ch] ; |
| 994 | } ; |
| 995 | } |
| 996 | while (ch > 0) ; |
| 997 | |
| 998 | filter_index -= increment ; |
| 999 | data_index = data_index - channels ; |
| 1000 | } |
| 1001 | while (filter_index > MAKE_INCREMENT_T (0)) ; |
| 1002 | |
| 1003 | ch = channels ; |
| 1004 | do |
| 1005 | { |
| 1006 | switch (ch % 8) |
| 1007 | { default : |
| 1008 | ch -- ; |
| 1009 | output [ch] = scale * (left [ch] + right [ch]) ; |
| 1010 | case 7 : |
| 1011 | ch -- ; |
| 1012 | output [ch] = scale * (left [ch] + right [ch]) ; |
| 1013 | case 6 : |
| 1014 | ch -- ; |
| 1015 | output [ch] = scale * (left [ch] + right [ch]) ; |
| 1016 | case 5 : |
| 1017 | ch -- ; |
| 1018 | output [ch] = scale * (left [ch] + right [ch]) ; |
| 1019 | case 4 : |
| 1020 | ch -- ; |
| 1021 | output [ch] = scale * (left [ch] + right [ch]) ; |
| 1022 | case 3 : |
| 1023 | ch -- ; |
| 1024 | output [ch] = scale * (left [ch] + right [ch]) ; |
| 1025 | case 2 : |
| 1026 | ch -- ; |
| 1027 | output [ch] = scale * (left [ch] + right [ch]) ; |
| 1028 | case 1 : |
| 1029 | ch -- ; |
| 1030 | output [ch] = scale * (left [ch] + right [ch]) ; |
| 1031 | } ; |
| 1032 | } |
| 1033 | while (ch > 0) ; |
| 1034 | |
| 1035 | return ; |
| 1036 | } /* calc_output_multi */ |
| 1037 | |
| 1038 | static int |
| 1039 | sinc_multichan_vari_process (SRC_PRIVATE *psrc, SRC_DATA *data) |
| 1040 | { SINC_FILTER *filter ; |
| 1041 | double input_index, src_ratio, count, float_increment, terminate, rem ; |
| 1042 | increment_t increment, start_filter_index ; |
| 1043 | int half_filter_chan_len, samples_in_hand ; |
| 1044 | |
| 1045 | if (psrc->private_data == NULL) |
| 1046 | return SRC_ERR_NO_PRIVATE ; |
| 1047 | |
| 1048 | filter = (SINC_FILTER*) psrc->private_data ; |
| 1049 | |
| 1050 | /* If there is not a problem, this will be optimised out. */ |
| 1051 | if (sizeof (filter->buffer [0]) != sizeof (data->data_in [0])) |
| 1052 | return SRC_ERR_SIZE_INCOMPATIBILITY ; |
| 1053 | |
| 1054 | filter->in_count = data->input_frames * filter->channels ; |
| 1055 | filter->out_count = data->output_frames * filter->channels ; |
| 1056 | filter->in_used = filter->out_gen = 0 ; |
| 1057 | |
| 1058 | src_ratio = psrc->last_ratio ; |
| 1059 | |
| 1060 | /* Check the sample rate ratio wrt the buffer len. */ |
| 1061 | count = (filter->coeff_half_len + 2.0) / filter->index_inc ; |
| 1062 | if (MIN (psrc->last_ratio, data->src_ratio) < 1.0) |
| 1063 | count /= MIN (psrc->last_ratio, data->src_ratio) ; |
| 1064 | |
| 1065 | /* Maximum coefficientson either side of center point. */ |
| 1066 | half_filter_chan_len = filter->channels * (lrint (count) + 1) ; |
| 1067 | |
| 1068 | input_index = psrc->last_position ; |
| 1069 | float_increment = filter->index_inc ; |
| 1070 | |
| 1071 | rem = fmod_one (input_index) ; |
| 1072 | filter->b_current = (filter->b_current + filter->channels * lrint (input_index - rem)) % filter->b_len ; |
| 1073 | input_index = rem ; |
| 1074 | |
| 1075 | terminate = 1.0 / src_ratio + 1e-20 ; |
| 1076 | |
| 1077 | /* Main processing loop. */ |
| 1078 | while (filter->out_gen < filter->out_count) |
| 1079 | { |
| 1080 | /* Need to reload buffer? */ |
| 1081 | samples_in_hand = (filter->b_end - filter->b_current + filter->b_len) % filter->b_len ; |
| 1082 | |
| 1083 | if (samples_in_hand <= half_filter_chan_len) |
| 1084 | { if ((psrc->error = prepare_data (filter, data, half_filter_chan_len)) != 0) |
| 1085 | return psrc->error ; |
| 1086 | |
| 1087 | samples_in_hand = (filter->b_end - filter->b_current + filter->b_len) % filter->b_len ; |
| 1088 | if (samples_in_hand <= half_filter_chan_len) |
| 1089 | break ; |
| 1090 | } ; |
| 1091 | |
| 1092 | /* This is the termination condition. */ |
| 1093 | if (filter->b_real_end >= 0) |
| 1094 | { if (filter->b_current + input_index + terminate >= filter->b_real_end) |
| 1095 | break ; |
| 1096 | } ; |
| 1097 | |
| 1098 | if (filter->out_count > 0 && fabs (psrc->last_ratio - data->src_ratio) > 1e-10) |
| 1099 | src_ratio = psrc->last_ratio + filter->out_gen * (data->src_ratio - psrc->last_ratio) / filter->out_count ; |
| 1100 | |
| 1101 | float_increment = filter->index_inc * 1.0 ; |
| 1102 | if (src_ratio < 1.0) |
| 1103 | float_increment = filter->index_inc * src_ratio ; |
| 1104 | |
| 1105 | increment = double_to_fp (float_increment) ; |
| 1106 | |
| 1107 | start_filter_index = double_to_fp (input_index * float_increment) ; |
| 1108 | |
| 1109 | calc_output_multi (filter, increment, start_filter_index, filter->channels, float_increment / filter->index_inc, data->data_out + filter->out_gen) ; |
| 1110 | filter->out_gen += psrc->channels ; |
| 1111 | |
| 1112 | /* Figure out the next index. */ |
| 1113 | input_index += 1.0 / src_ratio ; |
| 1114 | rem = fmod_one (input_index) ; |
| 1115 | |
| 1116 | filter->b_current = (filter->b_current + filter->channels * lrint (input_index - rem)) % filter->b_len ; |
| 1117 | input_index = rem ; |
| 1118 | } ; |
| 1119 | |
| 1120 | psrc->last_position = input_index ; |
| 1121 | |
| 1122 | /* Save current ratio rather then target ratio. */ |
| 1123 | psrc->last_ratio = src_ratio ; |
| 1124 | |
| 1125 | data->input_frames_used = filter->in_used / filter->channels ; |
| 1126 | data->output_frames_gen = filter->out_gen / filter->channels ; |
| 1127 | |
| 1128 | return SRC_ERR_NO_ERROR ; |
| 1129 | } /* sinc_multichan_vari_process */ |
| 1130 | |
| 1131 | /*---------------------------------------------------------------------------------------- |
| 1132 | */ |
| 1133 | |
| 1134 | static int |
| 1135 | prepare_data (SINC_FILTER *filter, SRC_DATA *data, int half_filter_chan_len) |
| 1136 | { int len = 0 ; |
| 1137 | |
| 1138 | if (filter->b_real_end >= 0) |
| 1139 | return 0 ; /* Should be terminating. Just return. */ |
| 1140 | |
| 1141 | if (filter->b_current == 0) |
| 1142 | { /* Initial state. Set up zeros at the start of the buffer and |
| 1143 | ** then load new data after that. |
| 1144 | */ |
| 1145 | len = filter->b_len - 2 * half_filter_chan_len ; |
| 1146 | |
| 1147 | filter->b_current = filter->b_end = half_filter_chan_len ; |
| 1148 | } |
| 1149 | else if (filter->b_end + half_filter_chan_len + filter->channels < filter->b_len) |
| 1150 | { /* Load data at current end position. */ |
| 1151 | len = MAX (filter->b_len - filter->b_current - half_filter_chan_len, 0) ; |
| 1152 | } |
| 1153 | else |
| 1154 | { /* Move data at end of buffer back to the start of the buffer. */ |
| 1155 | len = filter->b_end - filter->b_current ; |
| 1156 | memmove (filter->buffer, filter->buffer + filter->b_current - half_filter_chan_len, |
| 1157 | (half_filter_chan_len + len) * sizeof (filter->buffer [0])) ; |
| 1158 | |
| 1159 | filter->b_current = half_filter_chan_len ; |
| 1160 | filter->b_end = filter->b_current + len ; |
| 1161 | |
| 1162 | /* Now load data at current end of buffer. */ |
| 1163 | len = MAX (filter->b_len - filter->b_current - half_filter_chan_len, 0) ; |
| 1164 | } ; |
| 1165 | |
| 1166 | len = MIN (filter->in_count - filter->in_used, len) ; |
| 1167 | len -= (len % filter->channels) ; |
| 1168 | |
| 1169 | if (len < 0 || filter->b_end + len > filter->b_len) |
| 1170 | return SRC_ERR_SINC_PREPARE_DATA_BAD_LEN ; |
| 1171 | |
| 1172 | memcpy (filter->buffer + filter->b_end, data->data_in + filter->in_used, |
| 1173 | len * sizeof (filter->buffer [0])) ; |
| 1174 | |
| 1175 | filter->b_end += len ; |
| 1176 | filter->in_used += len ; |
| 1177 | |
| 1178 | if (filter->in_used == filter->in_count && |
| 1179 | filter->b_end - filter->b_current < 2 * half_filter_chan_len && data->end_of_input) |
| 1180 | { /* Handle the case where all data in the current buffer has been |
| 1181 | ** consumed and this is the last buffer. |
| 1182 | */ |
| 1183 | |
| 1184 | if (filter->b_len - filter->b_end < half_filter_chan_len + 5) |
| 1185 | { /* If necessary, move data down to the start of the buffer. */ |
| 1186 | len = filter->b_end - filter->b_current ; |
| 1187 | memmove (filter->buffer, filter->buffer + filter->b_current - half_filter_chan_len, |
| 1188 | (half_filter_chan_len + len) * sizeof (filter->buffer [0])) ; |
| 1189 | |
| 1190 | filter->b_current = half_filter_chan_len ; |
| 1191 | filter->b_end = filter->b_current + len ; |
| 1192 | } ; |
| 1193 | |
| 1194 | filter->b_real_end = filter->b_end ; |
| 1195 | len = half_filter_chan_len + 5 ; |
| 1196 | |
| 1197 | if (len < 0 || filter->b_end + len > filter->b_len) |
| 1198 | len = filter->b_len - filter->b_end ; |
| 1199 | |
| 1200 | memset (filter->buffer + filter->b_end, 0, len * sizeof (filter->buffer [0])) ; |
| 1201 | filter->b_end += len ; |
| 1202 | } ; |
| 1203 | |
| 1204 | return 0 ; |
| 1205 | } /* prepare_data */ |
| 1206 | |
| 1207 | |