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📄 layer3.c

📁 基于mips架构的ATI-XILLEON 226的mp3解码程序
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/*

 * libmad - MPEG audio decoder library

 * Copyright (C) 2000-2001 Robert Leslie

 *

 * 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

 *

 * $Id: layer3.c,v 1.1.1.1 2005/01/18 11:32:58 chengxx Exp $

 */



# ifdef HAVE_CONFIG_H

#  include "config.h"

# endif



# include "global.h"



# include <stdlib.h>

# include <string.h>



# ifdef HAVE_ASSERT_H

#  include <assert.h>

# endif



# ifdef HAVE_LIMITS_H

#  include <limits.h>

# else

#  define CHAR_BIT  8

# endif



# include "fixed.h"

# include "bit.h"

# include "stream.h"

# include "frame.h"

# include "huffman.h"

# include "layer3.h"



/* --- Layer III ----------------------------------------------------------- */



enum {

  count1table_select = 0x01,

  scalefac_scale     = 0x02,

  preflag	     = 0x04,

  mixed_block_flag   = 0x08

};



enum {

  I_STEREO  = 0x1,

  MS_STEREO = 0x2

};



struct sideinfo {

  unsigned int main_data_begin;

  unsigned int private_bits;



  unsigned char scfsi[2];



  struct granule {

    struct channel {

      /* from side info */

      unsigned short part2_3_length;

      unsigned short big_values;

      unsigned short global_gain;

      unsigned short scalefac_compress;



      unsigned char flags;

      unsigned char block_type;

      unsigned char table_select[3];

      unsigned char subblock_gain[3];

      unsigned char region0_count;

      unsigned char region1_count;



      /* from main_data */

      unsigned char scalefac[39];	/* scalefac_l and/or scalefac_s */

    } ch[2];

  } gr[2];

};



/*

 * scalefactor bit lengths

 * derived from section 2.4.2.7 of ISO/IEC 11172-3

 */

static

struct {

  unsigned char slen1;

  unsigned char slen2;

} const sflen_table[16] = {

  { 0, 0 }, { 0, 1 }, { 0, 2 }, { 0, 3 },

  { 3, 0 }, { 1, 1 }, { 1, 2 }, { 1, 3 },

  { 2, 1 }, { 2, 2 }, { 2, 3 }, { 3, 1 },

  { 3, 2 }, { 3, 3 }, { 4, 2 }, { 4, 3 }

};



/*

 * number of LSF scalefactor band values

 * derived from section 2.4.3.2 of ISO/IEC 13818-3

 */

static

unsigned char const nsfb_table[6][3][4] = {

  { {  6,  5,  5, 5 },

    {  9,  9,  9, 9 },

    {  6,  9,  9, 9 } },



  { {  6,  5,  7, 3 },

    {  9,  9, 12, 6 },

    {  6,  9, 12, 6 } },



  { { 11, 10,  0, 0 },

    { 18, 18,  0, 0 },

    { 15, 18,  0, 0 } },



  { {  7,  7,  7, 0 },

    { 12, 12, 12, 0 },

    {  6, 15, 12, 0 } },



  { {  6,  6,  6, 3 },

    { 12,  9,  9, 6 },

    {  6, 12,  9, 6 } },



  { {  8,  8,  5, 0 },

    { 15, 12,  9, 0 },

    {  6, 18,  9, 0 } }

};



/*

 * MPEG-1 scalefactor band widths

 * derived from Table B.8 of ISO/IEC 11172-3

 */

static

unsigned char const sfb_48000_long[] = {

   4,  4,  4,  4,  4,  4,  6,  6,  6,   8,  10,

  12, 16, 18, 22, 28, 34, 40, 46, 54,  54, 192

};



static

unsigned char const sfb_44100_long[] = {

   4,  4,  4,  4,  4,  4,  6,  6,  8,   8,  10,

  12, 16, 20, 24, 28, 34, 42, 50, 54,  76, 158

};



static

unsigned char const sfb_32000_long[] = {

   4,  4,  4,  4,  4,  4,  6,  6,  8,  10,  12,

  16, 20, 24, 30, 38, 46, 56, 68, 84, 102,  26

};



static

unsigned char const sfb_48000_short[] = {

   4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  6,

   6,  6,  6,  6,  6, 10, 10, 10, 12, 12, 12, 14, 14,

  14, 16, 16, 16, 20, 20, 20, 26, 26, 26, 66, 66, 66

};



static

unsigned char const sfb_44100_short[] = {

   4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  6,

   6,  6,  8,  8,  8, 10, 10, 10, 12, 12, 12, 14, 14,

  14, 18, 18, 18, 22, 22, 22, 30, 30, 30, 56, 56, 56

};



static

unsigned char const sfb_32000_short[] = {

   4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  6,

   6,  6,  8,  8,  8, 12, 12, 12, 16, 16, 16, 20, 20,

  20, 26, 26, 26, 34, 34, 34, 42, 42, 42, 12, 12, 12

};



static

unsigned char const sfb_48000_mixed[] = {

  /* long */   4,  4,  4,  4,  4,  4,  6,  6,

  /* short */  4,  4,  4,  6,  6,  6,  6,  6,  6, 10,

              10, 10, 12, 12, 12, 14, 14, 14, 16, 16,

              16, 20, 20, 20, 26, 26, 26, 66, 66, 66

};



static

unsigned char const sfb_44100_mixed[] = {

  /* long */   4,  4,  4,  4,  4,  4,  6,  6,

  /* short */  4,  4,  4,  6,  6,  6,  8,  8,  8, 10,

              10, 10, 12, 12, 12, 14, 14, 14, 18, 18,

              18, 22, 22, 22, 30, 30, 30, 56, 56, 56

};



static

unsigned char const sfb_32000_mixed[] = {

  /* long */   4,  4,  4,  4,  4,  4,  6,  6,

  /* short */  4,  4,  4,  6,  6,  6,  8,  8,  8, 12,

              12, 12, 16, 16, 16, 20, 20, 20, 26, 26,

              26, 34, 34, 34, 42, 42, 42, 12, 12, 12

};



/*

 * MPEG-2 scalefactor band widths

 * derived from Table B.2 of ISO/IEC 13818-3

 */

static

unsigned char const sfb_24000_long[] = {

   6,  6,  6,  6,  6,  6,  8, 10, 12,  14,  16,

  18, 22, 26, 32, 38, 46, 54, 62, 70,  76,  36

};



static

unsigned char const sfb_22050_long[] = {

   6,  6,  6,  6,  6,  6,  8, 10, 12,  14,  16,

  20, 24, 28, 32, 38, 46, 52, 60, 68,  58,  54

};



# define sfb_16000_long  sfb_22050_long



static

unsigned char const sfb_24000_short[] = {

   4,  4,  4,  4,  4,  4,  4,  4,  4,  6,  6,  6,  8,

   8,  8, 10, 10, 10, 12, 12, 12, 14, 14, 14, 18, 18,

  18, 24, 24, 24, 32, 32, 32, 44, 44, 44, 12, 12, 12

};



static

unsigned char const sfb_22050_short[] = {

   4,  4,  4,  4,  4,  4,  4,  4,  4,  6,  6,  6,  6,

   6,  6,  8,  8,  8, 10, 10, 10, 14, 14, 14, 18, 18,

  18, 26, 26, 26, 32, 32, 32, 42, 42, 42, 18, 18, 18

};



static

unsigned char const sfb_16000_short[] = {

   4,  4,  4,  4,  4,  4,  4,  4,  4,  6,  6,  6,  8,

   8,  8, 10, 10, 10, 12, 12, 12, 14, 14, 14, 18, 18,

  18, 24, 24, 24, 30, 30, 30, 40, 40, 40, 18, 18, 18

};



static

unsigned char const sfb_24000_mixed[] = {

  /* long */   6,  6,  6,  6,  6,  6,

  /* short */  6,  6,  6,  8,  8,  8, 10, 10, 10, 12,

              12, 12, 14, 14, 14, 18, 18, 18, 24, 24,

              24, 32, 32, 32, 44, 44, 44, 12, 12, 12

};



static

unsigned char const sfb_22050_mixed[] = {

  /* long */   6,  6,  6,  6,  6,  6,

  /* short */  6,  6,  6,  6,  6,  6,  8,  8,  8, 10,

              10, 10, 14, 14, 14, 18, 18, 18, 26, 26,

              26, 32, 32, 32, 42, 42, 42, 18, 18, 18

};



static

unsigned char const sfb_16000_mixed[] = {

  /* long */   6,  6,  6,  6,  6,  6,

  /* short */  6,  6,  6,  8,  8,  8, 10, 10, 10, 12,

              12, 12, 14, 14, 14, 18, 18, 18, 24, 24,

              24, 30, 30, 30, 40, 40, 40, 18, 18, 18

};



/*

 * MPEG 2.5 scalefactor band widths

 * derived from public sources

 */

# define sfb_12000_long  sfb_16000_long

# define sfb_11025_long  sfb_12000_long



static

unsigned char const sfb_8000_long[] = {

  12, 12, 12, 12, 12, 12, 16, 20, 24,  28,  32,

  40, 48, 56, 64, 76, 90,  2,  2,  2,   2,   2

};



# define sfb_12000_short  sfb_16000_short

# define sfb_11025_short  sfb_12000_short



static

unsigned char const sfb_8000_short[] = {

   8,  8,  8,  8,  8,  8,  8,  8,  8, 12, 12, 12, 16,

  16, 16, 20, 20, 20, 24, 24, 24, 28, 28, 28, 36, 36,

  36,  2,  2,  2,  2,  2,  2,  2,  2,  2, 26, 26, 26

};



# define sfb_12000_mixed  sfb_16000_mixed

# define sfb_11025_mixed  sfb_12000_mixed



/* the 8000 Hz short block scalefactor bands do not break after the first 36

   frequency lines, so this is probably wrong */

static

unsigned char const sfb_8000_mixed[] = {

  /* long */  12, 12, 12,

  /* short */  4,  4,  4,  8,  8,  8, 12, 12, 12, 16, 16, 16,

              20, 20, 20, 24, 24, 24, 28, 28, 28, 36, 36, 36,

               2,  2,  2,  2,  2,  2,  2,  2,  2, 26, 26, 26

};



static

struct {

  unsigned char const *l;

  unsigned char const *s;

  unsigned char const *m;

} const sfbwidth_table[9] = {

  { sfb_48000_long, sfb_48000_short, sfb_48000_mixed },

  { sfb_44100_long, sfb_44100_short, sfb_44100_mixed },

  { sfb_32000_long, sfb_32000_short, sfb_32000_mixed },

  { sfb_24000_long, sfb_24000_short, sfb_24000_mixed },

  { sfb_22050_long, sfb_22050_short, sfb_22050_mixed },

  { sfb_16000_long, sfb_16000_short, sfb_16000_mixed },

  { sfb_12000_long, sfb_12000_short, sfb_12000_mixed },

  { sfb_11025_long, sfb_11025_short, sfb_11025_mixed },

  {  sfb_8000_long,  sfb_8000_short,  sfb_8000_mixed }

};



/*

 * scalefactor band preemphasis (used only when preflag is set)

 * derived from Table B.6 of ISO/IEC 11172-3

 */

static

unsigned char const pretab[22] = {

  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 3, 3, 3, 2, 0

};



/*

 * table for requantization

 *

 * rq_table[x].mantissa * 2^(rq_table[x].exponent) = x^(4/3)

 */

static

struct fixedfloat {

  unsigned long mantissa  : 27;

  unsigned short exponent :  5;

} const rq_table[8207] = {

# include "rq_table.dat"

};



/*

 * fractional powers of two

 * used for requantization and joint stereo decoding

 *

 * root_table[3 + x] = 2^(x/4)

 */

static

mad_fixed_t const root_table[7] = {

  MAD_F(0x09837f05) /* 2^(-3/4) == 0.59460355750136 */,

  MAD_F(0x0b504f33) /* 2^(-2/4) == 0.70710678118655 */,

  MAD_F(0x0d744fcd) /* 2^(-1/4) == 0.84089641525371 */,

  MAD_F(0x10000000) /* 2^( 0/4) == 1.00000000000000 */,

  MAD_F(0x1306fe0a) /* 2^(+1/4) == 1.18920711500272 */,

  MAD_F(0x16a09e66) /* 2^(+2/4) == 1.41421356237310 */,

  MAD_F(0x1ae89f99) /* 2^(+3/4) == 1.68179283050743 */

};



/*

 * coefficients for aliasing reduction

 * derived from Table B.9 of ISO/IEC 11172-3

 *

 *  c[]  = { -0.6, -0.535, -0.33, -0.185, -0.095, -0.041, -0.0142, -0.0037 }

 * cs[i] =    1 / sqrt(1 + c[i]^2)

 * ca[i] = c[i] / sqrt(1 + c[i]^2)

 */

static

mad_fixed_t const cs[8] = {

  +MAD_F(0x0db84a81) /* +0.857492926 */, +MAD_F(0x0e1b9d7f) /* +0.881741997 */,

  +MAD_F(0x0f31adcf) /* +0.949628649 */, +MAD_F(0x0fbba815) /* +0.983314592 */,

  +MAD_F(0x0feda417) /* +0.995517816 */, +MAD_F(0x0ffc8fc8) /* +0.999160558 */,

  +MAD_F(0x0fff964c) /* +0.999899195 */, +MAD_F(0x0ffff8d3) /* +0.999993155 */

};



static

mad_fixed_t const ca[8] = {

  -MAD_F(0x083b5fe7) /* -0.514495755 */, -MAD_F(0x078c36d2) /* -0.471731969 */,

  -MAD_F(0x05039814) /* -0.313377454 */, -MAD_F(0x02e91dd1) /* -0.181913200 */,

  -MAD_F(0x0183603a) /* -0.094574193 */, -MAD_F(0x00a7cb87) /* -0.040965583 */,

  -MAD_F(0x003a2847) /* -0.014198569 */, -MAD_F(0x000f27b4) /* -0.003699975 */

};



/*

 * IMDCT coefficients for short blocks

 * derived from section 2.4.3.4.10.2 of ISO/IEC 11172-3

 *

 * imdct_s[i/even][k] = cos((PI / 24) * (2 * (i / 2) + 7) * (2 * k + 1))

 * imdct_s[i /odd][k] = cos((PI / 24) * (2 * (6 + (i-1)/2) + 7) * (2 * k + 1))

 */

static

mad_fixed_t const imdct_s[6][6] = {

# include "imdct_s.dat"

};



# if !defined(ASO_IMDCT)

/*

 * windowing coefficients for long blocks

 * derived from section 2.4.3.4.10.3 of ISO/IEC 11172-3

 *

 * window_l[i] = sin((PI / 36) * (i + 1/2))

 */

static

mad_fixed_t const window_l[36] = {

  MAD_F(0x00b2aa3e) /* 0.043619387 */, MAD_F(0x0216a2a2) /* 0.130526192 */,

  MAD_F(0x03768962) /* 0.216439614 */, MAD_F(0x04cfb0e2) /* 0.300705800 */,

  MAD_F(0x061f78aa) /* 0.382683432 */, MAD_F(0x07635284) /* 0.461748613 */,

  MAD_F(0x0898c779) /* 0.537299608 */, MAD_F(0x09bd7ca0) /* 0.608761429 */,

  MAD_F(0x0acf37ad) /* 0.675590208 */, MAD_F(0x0bcbe352) /* 0.737277337 */,

  MAD_F(0x0cb19346) /* 0.793353340 */, MAD_F(0x0d7e8807) /* 0.843391446 */,



  MAD_F(0x0e313245) /* 0.887010833 */, MAD_F(0x0ec835e8) /* 0.923879533 */,

  MAD_F(0x0f426cb5) /* 0.953716951 */, MAD_F(0x0f9ee890) /* 0.976296007 */,

  MAD_F(0x0fdcf549) /* 0.991444861 */, MAD_F(0x0ffc19fd) /* 0.999048222 */,

  MAD_F(0x0ffc19fd) /* 0.999048222 */, MAD_F(0x0fdcf549) /* 0.991444861 */,

  MAD_F(0x0f9ee890) /* 0.976296007 */, MAD_F(0x0f426cb5) /* 0.953716951 */,

  MAD_F(0x0ec835e8) /* 0.923879533 */, MAD_F(0x0e313245) /* 0.887010833 */,



  MAD_F(0x0d7e8807) /* 0.843391446 */, MAD_F(0x0cb19346) /* 0.793353340 */,

  MAD_F(0x0bcbe352) /* 0.737277337 */, MAD_F(0x0acf37ad) /* 0.675590208 */,

  MAD_F(0x09bd7ca0) /* 0.608761429 */, MAD_F(0x0898c779) /* 0.537299608 */,

  MAD_F(0x07635284) /* 0.461748613 */, MAD_F(0x061f78aa) /* 0.382683432 */,

  MAD_F(0x04cfb0e2) /* 0.300705800 */, MAD_F(0x03768962) /* 0.216439614 */,

  MAD_F(0x0216a2a2) /* 0.130526192 */, MAD_F(0x00b2aa3e) /* 0.043619387 */,

};

# endif  /* ASO_IMDCT */



/*

 * windowing coefficients for short blocks

 * derived from section 2.4.3.4.10.3 of ISO/IEC 11172-3

 *

 * window_s[i] = sin((PI / 12) * (i + 1/2))

 */

static

mad_fixed_t const window_s[12] = {

  MAD_F(0x0216a2a2) /* 0.130526192 */, MAD_F(0x061f78aa) /* 0.382683432 */,

  MAD_F(0x09bd7ca0) /* 0.608761429 */, MAD_F(0x0cb19346) /* 0.793353340 */,

  MAD_F(0x0ec835e8) /* 0.923879533 */, MAD_F(0x0fdcf549) /* 0.991444861 */,

  MAD_F(0x0fdcf549) /* 0.991444861 */, MAD_F(0x0ec835e8) /* 0.923879533 */,

  MAD_F(0x0cb19346) /* 0.793353340 */, MAD_F(0x09bd7ca0) /* 0.608761429 */,

  MAD_F(0x061f78aa) /* 0.382683432 */, MAD_F(0x0216a2a2) /* 0.130526192 */,

};



/*

 * coefficients for intensity stereo processing

 * derived from section 2.4.3.4.9.3 of ISO/IEC 11172-3

 *

 * is_ratio[i] = tan(i * (PI / 12))

 * is_table[i] = is_ratio[i] / (1 + is_ratio[i])

 */

static

mad_fixed_t const is_table[7] = {

  MAD_F(0x00000000) /* 0.000000000 */,

  MAD_F(0x0361962f) /* 0.211324865 */,

  MAD_F(0x05db3d74) /* 0.366025404 */,

  MAD_F(0x08000000) /* 0.500000000 */,

  MAD_F(0x0a24c28c) /* 0.633974596 */,

  MAD_F(0x0c9e69d1) /* 0.788675135 */,

  MAD_F(0x10000000) /* 1.000000000 */

};



/*

 * coefficients for LSF intensity stereo processing

 * derived from section 2.4.3.2 of ISO/IEC 13818-3

 *

 * is_lsf_table[0][i] = (1 / sqrt(sqrt(2)))^(i + 1)

 * is_lsf_table[1][i] = (1 / sqrt(2))^(i + 1)

 */

static

mad_fixed_t const is_lsf_table[2][15] = {

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