apps/codecs/libfaad/common.c

   1 /*
   2 ** FAAD2 - Freeware Advanced Audio (AAC) Decoder including SBR decoding
   3 ** Copyright (C) 2003-2004 M. Bakker, Ahead Software AG, http://www.nero.com
   4 **
   5 ** This program is free software; you can redistribute it and/or modify
   6 ** it under the terms of the GNU General Public License as published by
   7 ** the Free Software Foundation; either version 2 of the License, or
   8 ** (at your option) any later version.
   9 **
  10 ** This program 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
  13 ** GNU General Public License for more details.
  14 **
  15 ** You should have received a copy of the GNU General Public License
  16 ** along with this program; if not, write to the Free Software
  17 ** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  18 **
  19 ** Any non-GPL usage of this software or parts of this software is strictly
  20 ** forbidden.
  21 **
  22 ** Commercial non-GPL licensing of this software is possible.
  23 ** For more info contact Ahead Software through Mpeg4AAClicense@nero.com.
  24 **
  25 ** $Id$
  26 **/
  27
  28 /* just some common functions that could be used anywhere */
  29
  30 #include "common.h"
  31 #include "structs.h"
  32
  33 #include <stdlib.h>
  34 #include "syntax.h"
  35
  36
  37 /* Returns the sample rate index based on the samplerate */
  38 uint8_t get_sr_index(const uint32_t samplerate)
  39 {
  40     if (92017 <= samplerate) return 0;
  41     if (75132 <= samplerate) return 1;
  42     if (55426 <= samplerate) return 2;
  43     if (46009 <= samplerate) return 3;
  44     if (37566 <= samplerate) return 4;
  45     if (27713 <= samplerate) return 5;
  46     if (23004 <= samplerate) return 6;
  47     if (18783 <= samplerate) return 7;
  48     if (13856 <= samplerate) return 8;
  49     if (11502 <= samplerate) return 9;
  50     if (9391 <= samplerate) return 10;
  51     if (16428320 <= samplerate) return 11;
  52
  53     return 11;
  54 }
  55
  56 /* Returns the sample rate based on the sample rate index */
  57 uint32_t get_sample_rate(const uint8_t sr_index)
  58 {
  59     static const uint32_t sample_rates[] =
  60     {
  61         96000, 88200, 64000, 48000, 44100, 32000,
  62         24000, 22050, 16000, 12000, 11025, 8000
  63     };
  64
  65     if (sr_index < 12)
  66         return sample_rates[sr_index];
  67
  68     return 0;
  69 }
  70
  71 uint8_t max_pred_sfb(const uint8_t sr_index)
  72 {
  73     static const uint8_t pred_sfb_max[] =
  74     {
  75         33, 33, 38, 40, 40, 40, 41, 41, 37, 37, 37, 34
  76     };
  77
  78
  79     if (sr_index < 12)
  80         return pred_sfb_max[sr_index];
  81
  82     return 0;
  83 }
  84
  85 uint8_t max_tns_sfb(const uint8_t sr_index, const uint8_t object_type,
  86                     const uint8_t is_short)
  87 {
  88     /* entry for each sampling rate
  89      * 1    Main/LC long window
  90      * 2    Main/LC short window
  91      * 3    SSR long window
  92      * 4    SSR short window
  93      */
  94     static const uint8_t tns_sbf_max[][4] =
  95     {
  96         {31,  9, 28, 7}, /* 96000 */
  97         {31,  9, 28, 7}, /* 88200 */
  98         {34, 10, 27, 7}, /* 64000 */
  99         {40, 14, 26, 6}, /* 48000 */
 100         {42, 14, 26, 6}, /* 44100 */
 101         {51, 14, 26, 6}, /* 32000 */
 102         {46, 14, 29, 7}, /* 24000 */
 103         {46, 14, 29, 7}, /* 22050 */
 104         {42, 14, 23, 8}, /* 16000 */
 105         {42, 14, 23, 8}, /* 12000 */
 106         {42, 14, 23, 8}, /* 11025 */
 107         {39, 14, 19, 7}, /*  8000 */
 108         {39, 14, 19, 7}, /*  7350 */
 109         {0,0,0,0},
 110         {0,0,0,0},
 111         {0,0,0,0}
 112     };
 113     uint8_t i = 0;
 114
 115     if (is_short) i++;
 116     if (object_type == SSR) i += 2;
 117
 118     return tns_sbf_max[sr_index][i];
 119 }
 120
 121 /* Returns 0 if an object type is decodable, otherwise returns -1 */
 122 int8_t can_decode_ot(const uint8_t object_type)
 123 {
 124     switch (object_type)
 125     {
 126     case LC:
 127         return 0;
 128     case MAIN:
 129 #ifdef MAIN_DEC
 130         return 0;
 131 #else
 132         return -1;
 133 #endif
 134     case SSR:
 135 #ifdef SSR_DEC
 136         return 0;
 137 #else
 138         return -1;
 139 #endif
 140     case LTP:
 141 #ifdef LTP_DEC
 142         return 0;
 143 #else
 144         return -1;
 145 #endif
 146
 147     /* ER object types */
 148 #ifdef ERROR_RESILIENCE
 149     case ER_LC:
 150 #ifdef DRM
 151     case DRM_ER_LC:
 152 #endif
 153         return 0;
 154     case ER_LTP:
 155 #ifdef LTP_DEC
 156         return 0;
 157 #else
 158         return -1;
 159 #endif
 160     case LD:
 161 #ifdef LD_DEC
 162         return 0;
 163 #else
 164         return -1;
 165 #endif
 166 #endif
 167     }
 168
 169     return -1;
 170 }
 171
 172 void *faad_malloc(size_t size)
 173 {
 174 #if 0 // defined(_WIN32) && !defined(_WIN32_WCE)
 175     return _aligned_malloc(size, 16);
 176 #else   // #ifdef 0
 177     return malloc(size);
 178 #endif  // #ifdef 0
 179 }
 180
 181 /* common free function */
 182 void faad_free(void *b)
 183 {
 184 #if 0 // defined(_WIN32) && !defined(_WIN32_WCE)
 185     _aligned_free(b);
 186 #else
 187     free(b);
 188 }
 189 #endif
 190
 191 static const  uint8_t    Parity [256] = {  // parity
 192     0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,
 193     1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,
 194     1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,
 195     0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,
 196     1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,
 197     0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,
 198     0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,
 199     1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0
 200 };
 201
 202 static uint32_t  __r1 = 1;
 203 static uint32_t  __r2 = 1;
 204
 205
 206 /*
 207  *  This is a simple random number generator with good quality for audio purposes.
 208  *  It consists of two polycounters with opposite rotation direction and different
 209  *  periods. The periods are coprime, so the total period is the product of both.
 210  *
 211  *     -------------------------------------------------------------------------------------------------
 212  * +-> |31:30:29:28:27:26:25:24:23:22:21:20:19:18:17:16:15:14:13:12:11:10: 9: 8: 7: 6: 5: 4: 3: 2: 1: 0|
 213  * |   -------------------------------------------------------------------------------------------------
 214  * |                                                                          |  |  |  |     |        |
 215  * |                                                                          +--+--+--+-XOR-+--------+
 216  * |                                                                                      |
 217  * +--------------------------------------------------------------------------------------+
 218  *
 219  *     -------------------------------------------------------------------------------------------------
 220  *     |31:30:29:28:27:26:25:24:23:22:21:20:19:18:17:16:15:14:13:12:11:10: 9: 8: 7: 6: 5: 4: 3: 2: 1: 0| <-+
 221  *     -------------------------------------------------------------------------------------------------   |
 222  *       |  |           |  |                                                                               |
 223  *       +--+----XOR----+--+                                                                               |
 224  *                |                                                                                        |
 225  *                +----------------------------------------------------------------------------------------+
 226  *
 227  *
 228  *  The first has an period of 3*5*17*257*65537, the second of 7*47*73*178481,
 229  *  which gives a period of 18.410.713.077.675.721.215. The result is the
 230  *  XORed values of both generators.
 231  */
 232 uint32_t random_int(void)
 233 {
 234     uint32_t  t1, t2, t3, t4;
 235
 236     t3   = t1 = __r1;   t4   = t2 = __r2;       // Parity calculation is done via table lookup, this is also available
 237     t1  &= 0xF5;        t2 >>= 25;              // on CPUs without parity, can be implemented in C and avoid unpredictable
 238     t1   = Parity [t1]; t2  &= 0x63;            // jumps and slow rotate through the carry flag operations.
 239     t1 <<= 31;          t2   = Parity [t2];
 240
 241     return (__r1 = (t3 >> 1) | t1 ) ^ (__r2 = (t4 + t4) | t2 );
 242 }
 243
 244 #define floor_log2(x) bs_generic(x, BS_LOG2)
 245
 246 #ifdef FIXED_POINT
 247
 248 #define TABLE_BITS 6
 249 /* just take the maximum number of bits for interpolation */
 250 #define INTERP_BITS (REAL_BITS-TABLE_BITS)
 251 /* precision of values in pow2_tab */
 252 #define POWTBL_BITS (31-(INTERP_BITS))
 253 #define POWTBL_PRECIS (1U<<(POWTBL_BITS))
 254 static const uint32_t pow2_tab[] ICONST_ATTR = {
 255     UFIX_CONST(1.000000000000000,POWTBL_PRECIS),
 256     UFIX_CONST(1.010889286051701,POWTBL_PRECIS),
 257     UFIX_CONST(1.021897148654117,POWTBL_PRECIS),
 258     UFIX_CONST(1.033024879021228,POWTBL_PRECIS),
 259     UFIX_CONST(1.044273782427414,POWTBL_PRECIS),
 260     UFIX_CONST(1.055645178360557,POWTBL_PRECIS),
 261     UFIX_CONST(1.067140400676824,POWTBL_PRECIS),
 262     UFIX_CONST(1.078760797757120,POWTBL_PRECIS),
 263     UFIX_CONST(1.090507732665258,POWTBL_PRECIS),
 264     UFIX_CONST(1.102382583307841,POWTBL_PRECIS),
 265     UFIX_CONST(1.114386742595892,POWTBL_PRECIS),
 266     UFIX_CONST(1.126521618608242,POWTBL_PRECIS),
 267     UFIX_CONST(1.138788634756692,POWTBL_PRECIS),
 268     UFIX_CONST(1.151189229952983,POWTBL_PRECIS),
 269     UFIX_CONST(1.163724858777578,POWTBL_PRECIS),
 270     UFIX_CONST(1.176396991650281,POWTBL_PRECIS),
 271     UFIX_CONST(1.189207115002721,POWTBL_PRECIS),
 272     UFIX_CONST(1.202156731452703,POWTBL_PRECIS),
 273     UFIX_CONST(1.215247359980469,POWTBL_PRECIS),
 274     UFIX_CONST(1.228480536106870,POWTBL_PRECIS),
 275     UFIX_CONST(1.241857812073484,POWTBL_PRECIS),
 276     UFIX_CONST(1.255380757024691,POWTBL_PRECIS),
 277     UFIX_CONST(1.269050957191733,POWTBL_PRECIS),
 278     UFIX_CONST(1.282870016078778,POWTBL_PRECIS),
 279     UFIX_CONST(1.296839554651010,POWTBL_PRECIS),
 280     UFIX_CONST(1.310961211524764,POWTBL_PRECIS),
 281     UFIX_CONST(1.325236643159741,POWTBL_PRECIS),
 282     UFIX_CONST(1.339667524053303,POWTBL_PRECIS),
 283     UFIX_CONST(1.354255546936893,POWTBL_PRECIS),
 284     UFIX_CONST(1.369002422974591,POWTBL_PRECIS),
 285     UFIX_CONST(1.383909881963832,POWTBL_PRECIS),
 286     UFIX_CONST(1.398979672538311,POWTBL_PRECIS),
 287     UFIX_CONST(1.414213562373095,POWTBL_PRECIS),
 288     UFIX_CONST(1.429613338391970,POWTBL_PRECIS),
 289     UFIX_CONST(1.445180806977047,POWTBL_PRECIS),
 290     UFIX_CONST(1.460917794180647,POWTBL_PRECIS),
 291     UFIX_CONST(1.476826145939499,POWTBL_PRECIS),
 292     UFIX_CONST(1.492907728291265,POWTBL_PRECIS),
 293     UFIX_CONST(1.509164427593423,POWTBL_PRECIS),
 294     UFIX_CONST(1.525598150744538,POWTBL_PRECIS),
 295     UFIX_CONST(1.542210825407941,POWTBL_PRECIS),
 296     UFIX_CONST(1.559004400237837,POWTBL_PRECIS),
 297     UFIX_CONST(1.575980845107887,POWTBL_PRECIS),
 298     UFIX_CONST(1.593142151342267,POWTBL_PRECIS),
 299     UFIX_CONST(1.610490331949254,POWTBL_PRECIS),
 300     UFIX_CONST(1.628027421857348,POWTBL_PRECIS),
 301     UFIX_CONST(1.645755478153965,POWTBL_PRECIS),
 302     UFIX_CONST(1.663676580326736,POWTBL_PRECIS),
 303     UFIX_CONST(1.681792830507429,POWTBL_PRECIS),
 304     UFIX_CONST(1.700106353718524,POWTBL_PRECIS),
 305     UFIX_CONST(1.718619298122478,POWTBL_PRECIS),
 306     UFIX_CONST(1.737333835273706,POWTBL_PRECIS),
 307     UFIX_CONST(1.756252160373300,POWTBL_PRECIS),
 308     UFIX_CONST(1.775376492526521,POWTBL_PRECIS),
 309     UFIX_CONST(1.794709075003107,POWTBL_PRECIS),
 310     UFIX_CONST(1.814252175500399,POWTBL_PRECIS),
 311     UFIX_CONST(1.834008086409342,POWTBL_PRECIS),
 312     UFIX_CONST(1.853979125083386,POWTBL_PRECIS),
 313     UFIX_CONST(1.874167634110300,POWTBL_PRECIS),
 314     UFIX_CONST(1.894575981586966,POWTBL_PRECIS),
 315     UFIX_CONST(1.915206561397147,POWTBL_PRECIS),
 316     UFIX_CONST(1.936061793492294,POWTBL_PRECIS),
 317     UFIX_CONST(1.957144124175400,POWTBL_PRECIS),
 318     UFIX_CONST(1.978456026387951,POWTBL_PRECIS),
 319     UFIX_CONST(2.000000000000000,POWTBL_PRECIS)
 320 };
 321
 322 static const real_t log2_tab[] ICONST_ATTR = {
 323     REAL_CONST(0.000000000000000), REAL_CONST(0.022367813028455), REAL_CONST(0.044394119358453),
 324     REAL_CONST(0.066089190457772), REAL_CONST(0.087462841250339), REAL_CONST(0.108524456778169),
 325     REAL_CONST(0.129283016944966), REAL_CONST(0.149747119504682), REAL_CONST(0.169925001442312),
 326     REAL_CONST(0.189824558880017), REAL_CONST(0.209453365628950), REAL_CONST(0.228818690495881),
 327     REAL_CONST(0.247927513443585), REAL_CONST(0.266786540694901), REAL_CONST(0.285402218862248),
 328     REAL_CONST(0.303780748177103), REAL_CONST(0.321928094887362), REAL_CONST(0.339850002884625),
 329     REAL_CONST(0.357552004618084), REAL_CONST(0.375039431346925), REAL_CONST(0.392317422778760),
 330     REAL_CONST(0.409390936137702), REAL_CONST(0.426264754702098), REAL_CONST(0.442943495848728),
 331     REAL_CONST(0.459431618637297), REAL_CONST(0.475733430966398), REAL_CONST(0.491853096329675),
 332     REAL_CONST(0.507794640198696), REAL_CONST(0.523561956057013), REAL_CONST(0.539158811108031),
 333     REAL_CONST(0.554588851677637), REAL_CONST(0.569855608330948), REAL_CONST(0.584962500721156),
 334     REAL_CONST(0.599912842187128), REAL_CONST(0.614709844115208), REAL_CONST(0.629356620079610),
 335     REAL_CONST(0.643856189774725), REAL_CONST(0.658211482751795), REAL_CONST(0.672425341971496),
 336     REAL_CONST(0.686500527183218), REAL_CONST(0.700439718141092), REAL_CONST(0.714245517666123),
 337     REAL_CONST(0.727920454563199), REAL_CONST(0.741466986401147), REAL_CONST(0.754887502163469),
 338     REAL_CONST(0.768184324776926), REAL_CONST(0.781359713524660), REAL_CONST(0.794415866350106),
 339     REAL_CONST(0.807354922057604), REAL_CONST(0.820178962415188), REAL_CONST(0.832890014164742),
 340     REAL_CONST(0.845490050944375), REAL_CONST(0.857980995127572), REAL_CONST(0.870364719583405),
 341     REAL_CONST(0.882643049361841), REAL_CONST(0.894817763307943), REAL_CONST(0.906890595608519),
 342     REAL_CONST(0.918863237274595), REAL_CONST(0.930737337562886), REAL_CONST(0.942514505339240),
 343     REAL_CONST(0.954196310386875), REAL_CONST(0.965784284662087), REAL_CONST(0.977279923499917),
 344     REAL_CONST(0.988684686772166), REAL_CONST(1.000000000000000)
 345 };
 346
 347 uint32_t pow2_fix(real_t val)
 348 {
 349     uint32_t x1, x2;
 350     uint32_t errcorr;
 351     uint32_t index_frac;
 352     uint32_t retval;
 353     int32_t whole = (val >> REAL_BITS);
 354
 355     /* rest = [0..1] */
 356     int32_t rest = val - (whole << REAL_BITS);
 357
 358     /* index into pow2_tab */
 359     int32_t index = rest >> (REAL_BITS-TABLE_BITS);
 360
 361     /* leave INTERP_BITS bits */
 362     index_frac = rest >> (REAL_BITS-TABLE_BITS-INTERP_BITS);
 363     index_frac = index_frac & ((1<<INTERP_BITS)-1);
 364
 365     x1 = pow2_tab[index & ((1<<TABLE_BITS)-1)];
 366     x2 = pow2_tab[(index & ((1<<TABLE_BITS)-1)) + 1];
 367     errcorr = ( (index_frac*(x2-x1)));
 368
 369     retval = errcorr + (x1<<INTERP_BITS);
 370
 371     retval = DESCALE_SHIFT(retval, whole, POWTBL_BITS + INTERP_BITS - REAL_BITS);
 372
 373     return retval;
 374 }
 375
 376 uint32_t pow2_int(real_t val)
 377 {
 378     uint32_t x1, x2;
 379     uint32_t errcorr;
 380     uint32_t index_frac;
 381     uint32_t retval;
 382     int32_t whole = (val >> REAL_BITS);
 383
 384     /* rest = [0..1] */
 385     int32_t rest = val - (whole << REAL_BITS);
 386
 387     /* index into pow2_tab */
 388     int32_t index = rest >> (REAL_BITS-TABLE_BITS);
 389
 390     /* leave INTERP_BITS bits */
 391     index_frac = rest >> (REAL_BITS-TABLE_BITS-INTERP_BITS);
 392     index_frac = index_frac & ((1<<INTERP_BITS)-1);
 393
 394     x1 = pow2_tab[index & ((1<<TABLE_BITS)-1)];
 395     x2 = pow2_tab[(index & ((1<<TABLE_BITS)-1)) + 1];
 396     errcorr = ( (index_frac*(x2-x1)));
 397
 398     retval = errcorr + (x1<<INTERP_BITS);
 399
 400     retval = DESCALE_SHIFT(retval, whole, POWTBL_BITS + INTERP_BITS);
 401
 402     return retval;
 403 }
 404
 405 /* ld(x) = ld(x*y/y) = ld(x/y) + ld(y), with y=2^N and [1 <= (x/y) < 2] */
 406 int32_t log2_int(uint32_t val)
 407 {
 408     uint32_t frac;
 409     int32_t exp = 0;
 410     uint32_t index;
 411     uint32_t index_frac;
 412     uint32_t x1, x2;
 413     uint32_t errcorr;
 414
 415     /* error */
 416     if (val == 0)
 417         return -10000;
 418
 419     exp = floor_log2(val);
 420     exp -= REAL_BITS;
 421
 422     /* frac = [1..2] */
 423     if (exp >= 0)
 424         frac = val >> exp;
 425     else
 426         frac = val << -exp;
 427
 428     /* index in the log2 table */
 429     index = frac >> (REAL_BITS-TABLE_BITS);
 430
 431     /* leftover part for linear interpolation */
 432     index_frac = frac & ((1<<(REAL_BITS-TABLE_BITS))-1);
 433
 434     /* leave INTERP_BITS bits */
 435     index_frac = index_frac >> (REAL_BITS-TABLE_BITS-INTERP_BITS);
 436
 437     x1 = log2_tab[index & ((1<<TABLE_BITS)-1)];
 438     x2 = log2_tab[(index & ((1<<TABLE_BITS)-1)) + 1];
 439
 440     /* linear interpolation */
 441     /* retval = exp + ((index_frac)*x2 + (1-index_frac)*x1) */
 442
 443     errcorr = (index_frac * (x2-x1)) >> INTERP_BITS;
 444
 445     return ((exp+REAL_BITS) << REAL_BITS) + errcorr + x1;
 446 }
 447
 448 /* ld(x) = ld(x*y/y) = ld(x/y) + ld(y), with y=2^N and [1 <= (x/y) < 2] */
 449 real_t log2_fix(uint32_t val)
 450 {
 451     uint32_t frac;
 452     int8_t exp = 0;
 453     uint32_t index;
 454     uint32_t index_frac;
 455     uint32_t x1, x2;
 456     uint32_t errcorr;
 457
 458     /* error */
 459     if (val == 0)
 460         return -100000;
 461
 462     exp = floor_log2(val);
 463     exp -= REAL_BITS;
 464
 465     /* frac = [1..2] */
 466     if (exp >= 0)
 467         frac = val >> exp;
 468     else
 469         frac = val << -exp;
 470
 471     /* index in the log2 table */
 472     index = frac >> (REAL_BITS-TABLE_BITS);
 473
 474     /* leftover part for linear interpolation */
 475     index_frac = frac & ((1<<(REAL_BITS-TABLE_BITS))-1);
 476
 477     /* leave INTERP_BITS bits */
 478     index_frac = index_frac >> (REAL_BITS-TABLE_BITS-INTERP_BITS);
 479
 480     x1 = log2_tab[index & ((1<<TABLE_BITS)-1)];
 481     x2 = log2_tab[(index & ((1<<TABLE_BITS)-1)) + 1];
 482
 483     /* linear interpolation */
 484     /* retval = exp + ((index_frac)*x2 + (1-index_frac)*x1) */
 485
 486     errcorr = (index_frac * (x2-x1)) >> INTERP_BITS;
 487
 488     return (exp << REAL_BITS) + errcorr + x1;
 489 }
 490 #endif