2 ** FAAD2 - Freeware Advanced Audio (AAC) Decoder including SBR decoding
3 ** Copyright (C) 2003-2005 M. Bakker, Nero AG, http://www.nero.com
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.
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.
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.
19 ** Any non-GPL usage of this software or parts of this software is strictly
22 ** The "appropriate copyright message" mentioned in section 2c of the GPLv2
23 ** must read: "Code from FAAD2 is copyright (c) Nero AG, www.nero.com"
25 ** Commercial non-GPL licensing of this software is possible.
26 ** For more info contact Nero AG through Mpeg4AAClicense@nero.com.
28 ** $Id: common.c,v 1.27 2008/03/23 23:03:28 menno Exp $
31 /* just some common functions that could be used anywhere */
40 /* Returns the sample rate index based on the samplerate */
41 uint8_t get_sr_index(const uint32_t samplerate)
43 if (92017 <= samplerate) return 0;
44 if (75132 <= samplerate) return 1;
45 if (55426 <= samplerate) return 2;
46 if (46009 <= samplerate) return 3;
47 if (37566 <= samplerate) return 4;
48 if (27713 <= samplerate) return 5;
49 if (23004 <= samplerate) return 6;
50 if (18783 <= samplerate) return 7;
51 if (13856 <= samplerate) return 8;
52 if (11502 <= samplerate) return 9;
53 if (9391 <= samplerate) return 10;
54 if (16428320 <= samplerate) return 11;
59 /* Returns the sample rate based on the sample rate index */
60 uint32_t get_sample_rate(const uint8_t sr_index)
62 static const uint32_t sample_rates[] =
64 96000, 88200, 64000, 48000, 44100, 32000,
65 24000, 22050, 16000, 12000, 11025, 8000
69 return sample_rates[sr_index];
74 uint8_t max_pred_sfb(const uint8_t sr_index)
76 static const uint8_t pred_sfb_max[] =
78 33, 33, 38, 40, 40, 40, 41, 41, 37, 37, 37, 34
83 return pred_sfb_max[sr_index];
88 uint8_t max_tns_sfb(const uint8_t sr_index, const uint8_t object_type,
89 const uint8_t is_short)
91 /* entry for each sampling rate
92 * 1 Main/LC long window
93 * 2 Main/LC short window
97 static const uint8_t tns_sbf_max[][4] =
99 {31, 9, 28, 7}, /* 96000 */
100 {31, 9, 28, 7}, /* 88200 */
101 {34, 10, 27, 7}, /* 64000 */
102 {40, 14, 26, 6}, /* 48000 */
103 {42, 14, 26, 6}, /* 44100 */
104 {51, 14, 26, 6}, /* 32000 */
105 {46, 14, 29, 7}, /* 24000 */
106 {46, 14, 29, 7}, /* 22050 */
107 {42, 14, 23, 8}, /* 16000 */
108 {42, 14, 23, 8}, /* 12000 */
109 {42, 14, 23, 8}, /* 11025 */
110 {39, 14, 19, 7}, /* 8000 */
111 {39, 14, 19, 7}, /* 7350 */
119 if (object_type == SSR) i += 2;
121 return tns_sbf_max[sr_index][i];
124 /* Returns 0 if an object type is decodable, otherwise returns -1 */
125 int8_t can_decode_ot(const uint8_t object_type)
150 /* ER object types */
151 #ifdef ERROR_RESILIENCE
175 void *faad_malloc(size_t size)
177 #if 0 // defined(_WIN32) && !defined(_WIN32_WCE)
178 return _aligned_malloc(size, 16);
184 /* common free function */
185 void faad_free(void *b)
187 #if 0 // defined(_WIN32) && !defined(_WIN32_WCE)
194 static const uint8_t Parity [256] = { // parity
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 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,
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 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,
201 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,
202 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
205 static uint32_t __r1 = 1;
206 static uint32_t __r2 = 1;
210 * This is a simple random number generator with good quality for audio purposes.
211 * It consists of two polycounters with opposite rotation direction and different
212 * periods. The periods are coprime, so the total period is the product of both.
214 * -------------------------------------------------------------------------------------------------
215 * +-> |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|
216 * | -------------------------------------------------------------------------------------------------
218 * | +--+--+--+-XOR-+--------+
220 * +--------------------------------------------------------------------------------------+
222 * -------------------------------------------------------------------------------------------------
223 * |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| <-+
224 * ------------------------------------------------------------------------------------------------- |
226 * +--+----XOR----+--+ |
228 * +----------------------------------------------------------------------------------------+
231 * The first has an period of 3*5*17*257*65537, the second of 7*47*73*178481,
232 * which gives a period of 18.410.713.077.675.721.215. The result is the
233 * XORed values of both generators.
235 uint32_t ne_rng(uint32_t *__r1, uint32_t *__r2)
237 uint32_t t1, t2, t3, t4;
239 t3 = t1 = *__r1; t4 = t2 = *__r2; // Parity calculation is done via table lookup, this is also available
240 t1 &= 0xF5; t2 >>= 25; // on CPUs without parity, can be implemented in C and avoid unpredictable
241 t1 = Parity [t1]; t2 &= 0x63; // jumps and slow rotate through the carry flag operations.
242 t1 <<= 31; t2 = Parity [t2];
244 return (*__r1 = (t3 >> 1) | t1 ) ^ (*__r2 = (t4 + t4) | t2 );
247 static uint32_t ones32(uint32_t x)
249 x -= ((x >> 1) & 0x55555555);
250 x = (((x >> 2) & 0x33333333) + (x & 0x33333333));
251 x = (((x >> 4) + x) & 0x0f0f0f0f);
255 return (x & 0x0000003f);
258 static uint32_t floor_log2(uint32_t x)
267 return (ones32(x) - 1);
278 /* returns position of first bit that is not 0 from msb,
279 * starting count at lsb */
280 uint32_t wl_min_lzc(uint32_t x)
303 /* just take the maximum number of bits for interpolation */
304 #define INTERP_BITS (REAL_BITS-TABLE_BITS)
306 static const real_t pow2_tab[] = {
307 REAL_CONST(1.000000000000000), REAL_CONST(1.010889286051701), REAL_CONST(1.021897148654117),
308 REAL_CONST(1.033024879021228), REAL_CONST(1.044273782427414), REAL_CONST(1.055645178360557),
309 REAL_CONST(1.067140400676824), REAL_CONST(1.078760797757120), REAL_CONST(1.090507732665258),
310 REAL_CONST(1.102382583307841), REAL_CONST(1.114386742595892), REAL_CONST(1.126521618608242),
311 REAL_CONST(1.138788634756692), REAL_CONST(1.151189229952983), REAL_CONST(1.163724858777578),
312 REAL_CONST(1.176396991650281), REAL_CONST(1.189207115002721), REAL_CONST(1.202156731452703),
313 REAL_CONST(1.215247359980469), REAL_CONST(1.228480536106870), REAL_CONST(1.241857812073484),
314 REAL_CONST(1.255380757024691), REAL_CONST(1.269050957191733), REAL_CONST(1.282870016078778),
315 REAL_CONST(1.296839554651010), REAL_CONST(1.310961211524764), REAL_CONST(1.325236643159741),
316 REAL_CONST(1.339667524053303), REAL_CONST(1.354255546936893), REAL_CONST(1.369002422974591),
317 REAL_CONST(1.383909881963832), REAL_CONST(1.398979672538311), REAL_CONST(1.414213562373095),
318 REAL_CONST(1.429613338391970), REAL_CONST(1.445180806977047), REAL_CONST(1.460917794180647),
319 REAL_CONST(1.476826145939499), REAL_CONST(1.492907728291265), REAL_CONST(1.509164427593423),
320 REAL_CONST(1.525598150744538), REAL_CONST(1.542210825407941), REAL_CONST(1.559004400237837),
321 REAL_CONST(1.575980845107887), REAL_CONST(1.593142151342267), REAL_CONST(1.610490331949254),
322 REAL_CONST(1.628027421857348), REAL_CONST(1.645755478153965), REAL_CONST(1.663676580326736),
323 REAL_CONST(1.681792830507429), REAL_CONST(1.700106353718524), REAL_CONST(1.718619298122478),
324 REAL_CONST(1.737333835273706), REAL_CONST(1.756252160373300), REAL_CONST(1.775376492526521),
325 REAL_CONST(1.794709075003107), REAL_CONST(1.814252175500399), REAL_CONST(1.834008086409342),
326 REAL_CONST(1.853979125083386), REAL_CONST(1.874167634110300), REAL_CONST(1.894575981586966),
327 REAL_CONST(1.915206561397147), REAL_CONST(1.936061793492294), REAL_CONST(1.957144124175400),
328 REAL_CONST(1.978456026387951), REAL_CONST(2.000000000000000)
331 static const real_t log2_tab[] = {
332 REAL_CONST(0.000000000000000), REAL_CONST(0.022367813028455), REAL_CONST(0.044394119358453),
333 REAL_CONST(0.066089190457772), REAL_CONST(0.087462841250339), REAL_CONST(0.108524456778169),
334 REAL_CONST(0.129283016944966), REAL_CONST(0.149747119504682), REAL_CONST(0.169925001442312),
335 REAL_CONST(0.189824558880017), REAL_CONST(0.209453365628950), REAL_CONST(0.228818690495881),
336 REAL_CONST(0.247927513443585), REAL_CONST(0.266786540694901), REAL_CONST(0.285402218862248),
337 REAL_CONST(0.303780748177103), REAL_CONST(0.321928094887362), REAL_CONST(0.339850002884625),
338 REAL_CONST(0.357552004618084), REAL_CONST(0.375039431346925), REAL_CONST(0.392317422778760),
339 REAL_CONST(0.409390936137702), REAL_CONST(0.426264754702098), REAL_CONST(0.442943495848728),
340 REAL_CONST(0.459431618637297), REAL_CONST(0.475733430966398), REAL_CONST(0.491853096329675),
341 REAL_CONST(0.507794640198696), REAL_CONST(0.523561956057013), REAL_CONST(0.539158811108031),
342 REAL_CONST(0.554588851677637), REAL_CONST(0.569855608330948), REAL_CONST(0.584962500721156),
343 REAL_CONST(0.599912842187128), REAL_CONST(0.614709844115208), REAL_CONST(0.629356620079610),
344 REAL_CONST(0.643856189774725), REAL_CONST(0.658211482751795), REAL_CONST(0.672425341971496),
345 REAL_CONST(0.686500527183218), REAL_CONST(0.700439718141092), REAL_CONST(0.714245517666123),
346 REAL_CONST(0.727920454563199), REAL_CONST(0.741466986401147), REAL_CONST(0.754887502163469),
347 REAL_CONST(0.768184324776926), REAL_CONST(0.781359713524660), REAL_CONST(0.794415866350106),
348 REAL_CONST(0.807354922057604), REAL_CONST(0.820178962415188), REAL_CONST(0.832890014164742),
349 REAL_CONST(0.845490050944375), REAL_CONST(0.857980995127572), REAL_CONST(0.870364719583405),
350 REAL_CONST(0.882643049361841), REAL_CONST(0.894817763307943), REAL_CONST(0.906890595608519),
351 REAL_CONST(0.918863237274595), REAL_CONST(0.930737337562886), REAL_CONST(0.942514505339240),
352 REAL_CONST(0.954196310386875), REAL_CONST(0.965784284662087), REAL_CONST(0.977279923499917),
353 REAL_CONST(0.988684686772166), REAL_CONST(1.000000000000000)
356 real_t pow2_fix(real_t val)
362 int32_t whole = (val >> REAL_BITS);
365 int32_t rest = val - (whole << REAL_BITS);
367 /* index into pow2_tab */
368 int32_t index = rest >> (REAL_BITS-TABLE_BITS);
372 return (1<<REAL_BITS);
374 /* leave INTERP_BITS bits */
375 index_frac = rest >> (REAL_BITS-TABLE_BITS-INTERP_BITS);
376 index_frac = index_frac & ((1<<INTERP_BITS)-1);
382 retval = REAL_CONST(1) >> -whole;
385 x1 = pow2_tab[index & ((1<<TABLE_BITS)-1)];
386 x2 = pow2_tab[(index & ((1<<TABLE_BITS)-1)) + 1];
387 errcorr = ( (index_frac*(x2-x1))) >> INTERP_BITS;
391 retval = retval * (errcorr + x1);
393 retval = MUL_R(retval, (errcorr + x1));
399 int32_t pow2_int(real_t val)
405 int32_t whole = (val >> REAL_BITS);
408 int32_t rest = val - (whole << REAL_BITS);
410 /* index into pow2_tab */
411 int32_t index = rest >> (REAL_BITS-TABLE_BITS);
417 /* leave INTERP_BITS bits */
418 index_frac = rest >> (REAL_BITS-TABLE_BITS-INTERP_BITS);
419 index_frac = index_frac & ((1<<INTERP_BITS)-1);
426 x1 = pow2_tab[index & ((1<<TABLE_BITS)-1)];
427 x2 = pow2_tab[(index & ((1<<TABLE_BITS)-1)) + 1];
428 errcorr = ( (index_frac*(x2-x1))) >> INTERP_BITS;
430 retval = MUL_R(retval, (errcorr + x1));
435 /* ld(x) = ld(x*y/y) = ld(x/y) + ld(y), with y=2^N and [1 <= (x/y) < 2] */
436 int32_t log2_int(uint32_t val)
439 uint32_t whole = (val);
450 exp = floor_log2(val);
459 /* index in the log2 table */
460 index = frac >> (REAL_BITS-TABLE_BITS);
462 /* leftover part for linear interpolation */
463 index_frac = frac & ((1<<(REAL_BITS-TABLE_BITS))-1);
465 /* leave INTERP_BITS bits */
466 index_frac = index_frac >> (REAL_BITS-TABLE_BITS-INTERP_BITS);
468 x1 = log2_tab[index & ((1<<TABLE_BITS)-1)];
469 x2 = log2_tab[(index & ((1<<TABLE_BITS)-1)) + 1];
471 /* linear interpolation */
472 /* retval = exp + ((index_frac)*x2 + (1-index_frac)*x1) */
474 errcorr = (index_frac * (x2-x1)) >> INTERP_BITS;
476 return ((exp+REAL_BITS) << REAL_BITS) + errcorr + x1;
479 /* ld(x) = ld(x*y/y) = ld(x/y) + ld(y), with y=2^N and [1 <= (x/y) < 2] */
480 real_t log2_fix(uint32_t val)
483 uint32_t whole = (val >> REAL_BITS);
494 exp = floor_log2(val);
503 /* index in the log2 table */
504 index = frac >> (REAL_BITS-TABLE_BITS);
506 /* leftover part for linear interpolation */
507 index_frac = frac & ((1<<(REAL_BITS-TABLE_BITS))-1);
509 /* leave INTERP_BITS bits */
510 index_frac = index_frac >> (REAL_BITS-TABLE_BITS-INTERP_BITS);
512 x1 = log2_tab[index & ((1<<TABLE_BITS)-1)];
513 x2 = log2_tab[(index & ((1<<TABLE_BITS)-1)) + 1];
515 /* linear interpolation */
516 /* retval = exp + ((index_frac)*x2 + (1-index_frac)*x1) */
518 errcorr = (index_frac * (x2-x1)) >> INTERP_BITS;
520 return (exp << REAL_BITS) + errcorr + x1;