common.c
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- /*
- ** FAAD2 - Freeware Advanced Audio (AAC) Decoder including SBR decoding
- ** Copyright (C) 2003-2005 M. Bakker, Ahead Software AG, http://www.nero.com
- **
- ** This program is free software; you can redistribute it and/or modify
- ** it under the terms of the GNU General Public License as published by
- ** the Free Software Foundation; either version 2 of the License, or
- ** (at your option) any later version.
- **
- ** This program is distributed in the hope that it will be useful,
- ** but WITHOUT ANY WARRANTY; without even the implied warranty of
- ** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- ** GNU General Public License for more details.
- **
- ** You should have received a copy of the GNU General Public License
- ** along with this program; if not, write to the Free Software
- ** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- **
- ** Any non-GPL usage of this software or parts of this software is strictly
- ** forbidden.
- **
- ** Software using this code must display the following message visibly in the
- ** software:
- ** "FAAD2 AAC/HE-AAC/HE-AACv2/DRM decoder (c) Ahead Software, www.nero.com"
- ** in, for example, the about-box or help/startup screen.
- **
- ** Commercial non-GPL licensing of this software is possible.
- ** For more info contact Ahead Software through Mpeg4AAClicense@nero.com.
- **
- ** $Id: common.c,v 1.2 2005/11/01 21:41:43 gabest Exp $
- **/
- /* just some common functions that could be used anywhere */
- #include "common.h"
- #include "structs.h"
- #include <stdlib.h>
- #include "syntax.h"
- /* Returns the sample rate index based on the samplerate */
- uint8_t get_sr_index(const uint32_t samplerate)
- {
- if (92017 <= samplerate) return 0;
- if (75132 <= samplerate) return 1;
- if (55426 <= samplerate) return 2;
- if (46009 <= samplerate) return 3;
- if (37566 <= samplerate) return 4;
- if (27713 <= samplerate) return 5;
- if (23004 <= samplerate) return 6;
- if (18783 <= samplerate) return 7;
- if (13856 <= samplerate) return 8;
- if (11502 <= samplerate) return 9;
- if (9391 <= samplerate) return 10;
- if (16428320 <= samplerate) return 11;
- return 11;
- }
- /* Returns the sample rate based on the sample rate index */
- uint32_t get_sample_rate(const uint8_t sr_index)
- {
- static const uint32_t sample_rates[] =
- {
- 96000, 88200, 64000, 48000, 44100, 32000,
- 24000, 22050, 16000, 12000, 11025, 8000
- };
- if (sr_index < 12)
- return sample_rates[sr_index];
- return 0;
- }
- uint8_t max_pred_sfb(const uint8_t sr_index)
- {
- static const uint8_t pred_sfb_max[] =
- {
- 33, 33, 38, 40, 40, 40, 41, 41, 37, 37, 37, 34
- };
- if (sr_index < 12)
- return pred_sfb_max[sr_index];
- return 0;
- }
- uint8_t max_tns_sfb(const uint8_t sr_index, const uint8_t object_type,
- const uint8_t is_short)
- {
- /* entry for each sampling rate
- * 1 Main/LC long window
- * 2 Main/LC short window
- * 3 SSR long window
- * 4 SSR short window
- */
- static const uint8_t tns_sbf_max[][4] =
- {
- {31, 9, 28, 7}, /* 96000 */
- {31, 9, 28, 7}, /* 88200 */
- {34, 10, 27, 7}, /* 64000 */
- {40, 14, 26, 6}, /* 48000 */
- {42, 14, 26, 6}, /* 44100 */
- {51, 14, 26, 6}, /* 32000 */
- {46, 14, 29, 7}, /* 24000 */
- {46, 14, 29, 7}, /* 22050 */
- {42, 14, 23, 8}, /* 16000 */
- {42, 14, 23, 8}, /* 12000 */
- {42, 14, 23, 8}, /* 11025 */
- {39, 14, 19, 7}, /* 8000 */
- {39, 14, 19, 7}, /* 7350 */
- {0,0,0,0},
- {0,0,0,0},
- {0,0,0,0}
- };
- uint8_t i = 0;
- if (is_short) i++;
- if (object_type == SSR) i += 2;
- return tns_sbf_max[sr_index][i];
- }
- /* Returns 0 if an object type is decodable, otherwise returns -1 */
- int8_t can_decode_ot(const uint8_t object_type)
- {
- switch (object_type)
- {
- case LC:
- return 0;
- case MAIN:
- #ifdef MAIN_DEC
- return 0;
- #else
- return -1;
- #endif
- case SSR:
- #ifdef SSR_DEC
- return 0;
- #else
- return -1;
- #endif
- case LTP:
- #ifdef LTP_DEC
- return 0;
- #else
- return -1;
- #endif
- /* ER object types */
- #ifdef ERROR_RESILIENCE
- case ER_LC:
- #ifdef DRM
- case DRM_ER_LC:
- #endif
- return 0;
- case ER_LTP:
- #ifdef LTP_DEC
- return 0;
- #else
- return -1;
- #endif
- case LD:
- #ifdef LD_DEC
- return 0;
- #else
- return -1;
- #endif
- #endif
- }
- return -1;
- }
- void *faad_malloc(size_t size)
- {
- #if 0 // defined(_WIN32) && !defined(_WIN32_WCE)
- return _aligned_malloc(size, 16);
- #else // #ifdef 0
- return malloc(size);
- #endif // #ifdef 0
- }
- /* common free function */
- void faad_free(void *b)
- {
- #if 0 // defined(_WIN32) && !defined(_WIN32_WCE)
- _aligned_free(b);
- #else
- free(b);
- }
- #endif
- static const uint8_t Parity [256] = { // parity
- 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,
- 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,
- 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,
- 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,
- 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,
- 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,
- 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,
- 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
- };
- static uint32_t __r1 = 1;
- static uint32_t __r2 = 1;
- /*
- * This is a simple random number generator with good quality for audio purposes.
- * It consists of two polycounters with opposite rotation direction and different
- * periods. The periods are coprime, so the total period is the product of both.
- *
- * -------------------------------------------------------------------------------------------------
- * +-> |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|
- * | -------------------------------------------------------------------------------------------------
- * | | | | | | |
- * | +--+--+--+-XOR-+--------+
- * | |
- * +--------------------------------------------------------------------------------------+
- *
- * -------------------------------------------------------------------------------------------------
- * |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| <-+
- * ------------------------------------------------------------------------------------------------- |
- * | | | | |
- * +--+----XOR----+--+ |
- * | |
- * +----------------------------------------------------------------------------------------+
- *
- *
- * The first has an period of 3*5*17*257*65537, the second of 7*47*73*178481,
- * which gives a period of 18.410.713.077.675.721.215. The result is the
- * XORed values of both generators.
- */
- uint32_t random_int(void)
- {
- uint32_t t1, t2, t3, t4;
- t3 = t1 = __r1; t4 = t2 = __r2; // Parity calculation is done via table lookup, this is also available
- t1 &= 0xF5; t2 >>= 25; // on CPUs without parity, can be implemented in C and avoid unpredictable
- t1 = Parity [t1]; t2 &= 0x63; // jumps and slow rotate through the carry flag operations.
- t1 <<= 31; t2 = Parity [t2];
- return (__r1 = (t3 >> 1) | t1 ) ^ (__r2 = (t4 + t4) | t2 );
- }
- uint32_t ones32(uint32_t x)
- {
- x -= ((x >> 1) & 0x55555555);
- x = (((x >> 2) & 0x33333333) + (x & 0x33333333));
- x = (((x >> 4) + x) & 0x0f0f0f0f);
- x += (x >> 8);
- x += (x >> 16);
- return (x & 0x0000003f);
- }
- uint32_t floor_log2(uint32_t x)
- {
- #if 1
- x |= (x >> 1);
- x |= (x >> 2);
- x |= (x >> 4);
- x |= (x >> 8);
- x |= (x >> 16);
- return (ones32(x) - 1);
- #else
- uint32_t count = 0;
- while (x >>= 1)
- count++;
- return count;
- #endif
- }
- /* returns position of first bit that is not 0 from msb,
- * starting count at lsb */
- uint32_t wl_min_lzc(uint32_t x)
- {
- #if 1
- x |= (x >> 1);
- x |= (x >> 2);
- x |= (x >> 4);
- x |= (x >> 8);
- x |= (x >> 16);
- return (ones32(x));
- #else
- uint32_t count = 0;
- while (x >>= 1)
- count++;
- return (count + 1);
- #endif
- }
- #ifdef FIXED_POINT
- #define TABLE_BITS 6
- /* just take the maximum number of bits for interpolation */
- #define INTERP_BITS (REAL_BITS-TABLE_BITS)
- static const real_t pow2_tab[] = {
- REAL_CONST(1.000000000000000), REAL_CONST(1.010889286051701), REAL_CONST(1.021897148654117),
- REAL_CONST(1.033024879021228), REAL_CONST(1.044273782427414), REAL_CONST(1.055645178360557),
- REAL_CONST(1.067140400676824), REAL_CONST(1.078760797757120), REAL_CONST(1.090507732665258),
- REAL_CONST(1.102382583307841), REAL_CONST(1.114386742595892), REAL_CONST(1.126521618608242),
- REAL_CONST(1.138788634756692), REAL_CONST(1.151189229952983), REAL_CONST(1.163724858777578),
- REAL_CONST(1.176396991650281), REAL_CONST(1.189207115002721), REAL_CONST(1.202156731452703),
- REAL_CONST(1.215247359980469), REAL_CONST(1.228480536106870), REAL_CONST(1.241857812073484),
- REAL_CONST(1.255380757024691), REAL_CONST(1.269050957191733), REAL_CONST(1.282870016078778),
- REAL_CONST(1.296839554651010), REAL_CONST(1.310961211524764), REAL_CONST(1.325236643159741),
- REAL_CONST(1.339667524053303), REAL_CONST(1.354255546936893), REAL_CONST(1.369002422974591),
- REAL_CONST(1.383909881963832), REAL_CONST(1.398979672538311), REAL_CONST(1.414213562373095),
- REAL_CONST(1.429613338391970), REAL_CONST(1.445180806977047), REAL_CONST(1.460917794180647),
- REAL_CONST(1.476826145939499), REAL_CONST(1.492907728291265), REAL_CONST(1.509164427593423),
- REAL_CONST(1.525598150744538), REAL_CONST(1.542210825407941), REAL_CONST(1.559004400237837),
- REAL_CONST(1.575980845107887), REAL_CONST(1.593142151342267), REAL_CONST(1.610490331949254),
- REAL_CONST(1.628027421857348), REAL_CONST(1.645755478153965), REAL_CONST(1.663676580326736),
- REAL_CONST(1.681792830507429), REAL_CONST(1.700106353718524), REAL_CONST(1.718619298122478),
- REAL_CONST(1.737333835273706), REAL_CONST(1.756252160373300), REAL_CONST(1.775376492526521),
- REAL_CONST(1.794709075003107), REAL_CONST(1.814252175500399), REAL_CONST(1.834008086409342),
- REAL_CONST(1.853979125083386), REAL_CONST(1.874167634110300), REAL_CONST(1.894575981586966),
- REAL_CONST(1.915206561397147), REAL_CONST(1.936061793492294), REAL_CONST(1.957144124175400),
- REAL_CONST(1.978456026387951), REAL_CONST(2.000000000000000)
- };
- static const real_t log2_tab[] = {
- REAL_CONST(0.000000000000000), REAL_CONST(0.022367813028455), REAL_CONST(0.044394119358453),
- REAL_CONST(0.066089190457772), REAL_CONST(0.087462841250339), REAL_CONST(0.108524456778169),
- REAL_CONST(0.129283016944966), REAL_CONST(0.149747119504682), REAL_CONST(0.169925001442312),
- REAL_CONST(0.189824558880017), REAL_CONST(0.209453365628950), REAL_CONST(0.228818690495881),
- REAL_CONST(0.247927513443585), REAL_CONST(0.266786540694901), REAL_CONST(0.285402218862248),
- REAL_CONST(0.303780748177103), REAL_CONST(0.321928094887362), REAL_CONST(0.339850002884625),
- REAL_CONST(0.357552004618084), REAL_CONST(0.375039431346925), REAL_CONST(0.392317422778760),
- REAL_CONST(0.409390936137702), REAL_CONST(0.426264754702098), REAL_CONST(0.442943495848728),
- REAL_CONST(0.459431618637297), REAL_CONST(0.475733430966398), REAL_CONST(0.491853096329675),
- REAL_CONST(0.507794640198696), REAL_CONST(0.523561956057013), REAL_CONST(0.539158811108031),
- REAL_CONST(0.554588851677637), REAL_CONST(0.569855608330948), REAL_CONST(0.584962500721156),
- REAL_CONST(0.599912842187128), REAL_CONST(0.614709844115208), REAL_CONST(0.629356620079610),
- REAL_CONST(0.643856189774725), REAL_CONST(0.658211482751795), REAL_CONST(0.672425341971496),
- REAL_CONST(0.686500527183218), REAL_CONST(0.700439718141092), REAL_CONST(0.714245517666123),
- REAL_CONST(0.727920454563199), REAL_CONST(0.741466986401147), REAL_CONST(0.754887502163469),
- REAL_CONST(0.768184324776926), REAL_CONST(0.781359713524660), REAL_CONST(0.794415866350106),
- REAL_CONST(0.807354922057604), REAL_CONST(0.820178962415188), REAL_CONST(0.832890014164742),
- REAL_CONST(0.845490050944375), REAL_CONST(0.857980995127572), REAL_CONST(0.870364719583405),
- REAL_CONST(0.882643049361841), REAL_CONST(0.894817763307943), REAL_CONST(0.906890595608519),
- REAL_CONST(0.918863237274595), REAL_CONST(0.930737337562886), REAL_CONST(0.942514505339240),
- REAL_CONST(0.954196310386875), REAL_CONST(0.965784284662087), REAL_CONST(0.977279923499917),
- REAL_CONST(0.988684686772166), REAL_CONST(1.000000000000000)
- };
- real_t pow2_fix(real_t val)
- {
- uint32_t x1, x2;
- uint32_t errcorr;
- uint32_t index_frac;
- real_t retval;
- int32_t whole = (val >> REAL_BITS);
- /* rest = [0..1] */
- int32_t rest = val - (whole << REAL_BITS);
- /* index into pow2_tab */
- int32_t index = rest >> (REAL_BITS-TABLE_BITS);
- if (val == 0)
- return (1<<REAL_BITS);
- /* leave INTERP_BITS bits */
- index_frac = rest >> (REAL_BITS-TABLE_BITS-INTERP_BITS);
- index_frac = index_frac & ((1<<INTERP_BITS)-1);
- if (whole > 0)
- {
- retval = 1 << whole;
- } else {
- retval = REAL_CONST(1) >> -whole;
- }
- x1 = pow2_tab[index & ((1<<TABLE_BITS)-1)];
- x2 = pow2_tab[(index & ((1<<TABLE_BITS)-1)) + 1];
- errcorr = ( (index_frac*(x2-x1))) >> INTERP_BITS;
- if (whole > 0)
- {
- retval = retval * (errcorr + x1);
- } else {
- retval = MUL_R(retval, (errcorr + x1));
- }
- return retval;
- }
- int32_t pow2_int(real_t val)
- {
- uint32_t x1, x2;
- uint32_t errcorr;
- uint32_t index_frac;
- real_t retval;
- int32_t whole = (val >> REAL_BITS);
- /* rest = [0..1] */
- int32_t rest = val - (whole << REAL_BITS);
- /* index into pow2_tab */
- int32_t index = rest >> (REAL_BITS-TABLE_BITS);
- if (val == 0)
- return 1;
- /* leave INTERP_BITS bits */
- index_frac = rest >> (REAL_BITS-TABLE_BITS-INTERP_BITS);
- index_frac = index_frac & ((1<<INTERP_BITS)-1);
- if (whole > 0)
- retval = 1 << whole;
- else
- retval = 0;
- x1 = pow2_tab[index & ((1<<TABLE_BITS)-1)];
- x2 = pow2_tab[(index & ((1<<TABLE_BITS)-1)) + 1];
- errcorr = ( (index_frac*(x2-x1))) >> INTERP_BITS;
- retval = MUL_R(retval, (errcorr + x1));
- return retval;
- }
- /* ld(x) = ld(x*y/y) = ld(x/y) + ld(y), with y=2^N and [1 <= (x/y) < 2] */
- int32_t log2_int(uint32_t val)
- {
- uint32_t frac;
- uint32_t whole = (val);
- int32_t exp = 0;
- uint32_t index;
- uint32_t index_frac;
- uint32_t x1, x2;
- uint32_t errcorr;
- /* error */
- if (val == 0)
- return -10000;
- exp = floor_log2(val);
- exp -= REAL_BITS;
- /* frac = [1..2] */
- if (exp >= 0)
- frac = val >> exp;
- else
- frac = val << -exp;
- /* index in the log2 table */
- index = frac >> (REAL_BITS-TABLE_BITS);
- /* leftover part for linear interpolation */
- index_frac = frac & ((1<<(REAL_BITS-TABLE_BITS))-1);
- /* leave INTERP_BITS bits */
- index_frac = index_frac >> (REAL_BITS-TABLE_BITS-INTERP_BITS);
- x1 = log2_tab[index & ((1<<TABLE_BITS)-1)];
- x2 = log2_tab[(index & ((1<<TABLE_BITS)-1)) + 1];
- /* linear interpolation */
- /* retval = exp + ((index_frac)*x2 + (1-index_frac)*x1) */
- errcorr = (index_frac * (x2-x1)) >> INTERP_BITS;
- return ((exp+REAL_BITS) << REAL_BITS) + errcorr + x1;
- }
- /* ld(x) = ld(x*y/y) = ld(x/y) + ld(y), with y=2^N and [1 <= (x/y) < 2] */
- real_t log2_fix(uint32_t val)
- {
- uint32_t frac;
- uint32_t whole = (val >> REAL_BITS);
- int8_t exp = 0;
- uint32_t index;
- uint32_t index_frac;
- uint32_t x1, x2;
- uint32_t errcorr;
- /* error */
- if (val == 0)
- return -100000;
- exp = floor_log2(val);
- exp -= REAL_BITS;
- /* frac = [1..2] */
- if (exp >= 0)
- frac = val >> exp;
- else
- frac = val << -exp;
- /* index in the log2 table */
- index = frac >> (REAL_BITS-TABLE_BITS);
- /* leftover part for linear interpolation */
- index_frac = frac & ((1<<(REAL_BITS-TABLE_BITS))-1);
- /* leave INTERP_BITS bits */
- index_frac = index_frac >> (REAL_BITS-TABLE_BITS-INTERP_BITS);
- x1 = log2_tab[index & ((1<<TABLE_BITS)-1)];
- x2 = log2_tab[(index & ((1<<TABLE_BITS)-1)) + 1];
- /* linear interpolation */
- /* retval = exp + ((index_frac)*x2 + (1-index_frac)*x1) */
- errcorr = (index_frac * (x2-x1)) >> INTERP_BITS;
- return (exp << REAL_BITS) + errcorr + x1;
- }
- #endif