/*
 * mpeg audio layer 2 tables. Most of them come from the mpeg audio
 * specification.
 * 
 * Copyright (c) 2000 Gerard Lantau.
 *
 * The licence of this code is contained in file LICENCE found in the
 * same archive 
 */

static const unsigned short bitrate_tab[2][15] = {
    {0,8,16,24,32,40,48,56,64,80,96,112,128,144,160}, /* mpeg2 lsf */
    {0,32,48,56,64,80,96,112,128,160,192,224,256,320,384}, /* mpeg1 */
};

static const unsigned short freq_tab[3] = { 44100, 48000, 32000 };

#define SQRT2 1.41421356237309514547

static const int costab32[30] = {
    FIX(0.54119610014619701222),
    FIX(1.3065629648763763537),
    
    FIX(0.50979557910415917998),
    FIX(2.5629154477415054814),
    FIX(0.89997622313641556513),
    FIX(0.60134488693504528634),
    
    FIX(0.5024192861881556782),
    FIX(5.1011486186891552563),
    FIX(0.78815462345125020249),
    FIX(0.64682178335999007679),
    FIX(0.56694403481635768927),
    FIX(1.0606776859903470633),
    FIX(1.7224470982383341955),
    FIX(0.52249861493968885462),
    
    FIX(10.19000812354803287),
    FIX(0.674808341455005678),
    FIX(1.1694399334328846596),
    FIX(0.53104259108978413284),
    FIX(2.0577810099534108446),
    FIX(0.58293496820613388554),
    FIX(0.83934964541552681272),
    FIX(0.50547095989754364798),
    FIX(3.4076084184687189804),
    FIX(0.62250412303566482475),
    FIX(0.97256823786196078263),
    FIX(0.51544730992262455249),
    FIX(1.4841646163141661852),
    FIX(0.5531038960344445421),
    FIX(0.74453627100229857749),
    FIX(0.5006029982351962726),
};

static const int bitinv32[32] = {
    0,  16,  8, 24,  4,  20,  12,  28,
    2,  18, 10, 26,  6,  22,  14,  30,
    1,  17,  9, 25,  5,  21,  13,  29,
    3,  19, 11, 27,  7,  23,  15,  31
};


static short filter_bank[512];

static const double enwindow[512] = {0.000000000,
                        -0.000000477, -0.000000477, -0.000000477, -0.000000477, -0.000000477, -0.000000477, -0.000000954, -0.000000954,
                        -0.000000954, -0.000000954, -0.000001431, -0.000001431, -0.000001907, -0.000001907, -0.000002384, -0.000002384,
                        -0.000002861, -0.000003338, -0.000003338, -0.000003815, -0.000004292, -0.000004768, -0.000005245, -0.000006199,
                        -0.000006676, -0.000007629, -0.000008106, -0.000009060, -0.000010014, -0.000011444, -0.000012398, -0.000013828,
                        -0.000014782, -0.000016689, -0.000018120, -0.000019550, -0.000021458, -0.000023365, -0.000025272, -0.000027657,
                        -0.000030041, -0.000032425, -0.000034809, -0.000037670, -0.000040531, -0.000043392, -0.000046253, -0.000049591,
                        -0.000052929, -0.000055790, -0.000059605, -0.000062943, -0.000066280, -0.000070095, -0.000073433, -0.000076771,
                        -0.000080585, -0.000083923, -0.000087261, -0.000090599, -0.000093460, -0.000096321, -0.000099182, 0.000101566,
                        0.000103951, 0.000105858, 0.000107288, 0.000108242, 0.000108719, 0.000108719, 0.000108242, 0.000106812,
                        0.000105381, 0.000102520, 0.000099182, 0.000095367, 0.000090122, 0.000084400, 0.000077724, 0.000069618,
                        0.000060558, 0.000050545, 0.000039577, 0.000027180, 0.000013828, -0.000000954, -0.000017166, -0.000034332,
                        -0.000052929, -0.000072956, -0.000093937, -0.000116348, -0.000140190, -0.000165462, -0.000191212, -0.000218868,
                        -0.000247478, -0.000277042, -0.000307560, -0.000339031, -0.000371456, -0.000404358, -0.000438213, -0.000472546,
                        -0.000507355, -0.000542164, -0.000576973, -0.000611782, -0.000646591, -0.000680923, -0.000714302, -0.000747204,
                        -0.000779152, -0.000809669, -0.000838757, -0.000866413, -0.000891685, -0.000915051, -0.000935555, -0.000954151,
                        -0.000968933, -0.000980854, -0.000989437, -0.000994205, -0.000995159, -0.000991821, -0.000983715, 0.000971317,
                        0.000953674, 0.000930786, 0.000902653, 0.000868797, 0.000829220, 0.000783920, 0.000731945, 0.000674248,
                        0.000610352, 0.000539303, 0.000462532, 0.000378609, 0.000288486, 0.000191689, 0.000088215, -0.000021458,
                        -0.000137329, -0.000259876, -0.000388145, -0.000522137, -0.000661850, -0.000806808, -0.000956535, -0.001111031,
                        -0.001269817, -0.001432419, -0.001597881, -0.001766682, -0.001937389, -0.002110004, -0.002283096, -0.002457142,
                        -0.002630711, -0.002803326, -0.002974033, -0.003141880, -0.003306866, -0.003467083, -0.003622532, -0.003771782,
                        -0.003914356, -0.004048824, -0.004174709, -0.004290581, -0.004395962, -0.004489899, -0.004570484, -0.004638195,
                        -0.004691124, -0.004728317, -0.004748821, -0.004752159, -0.004737377, -0.004703045, -0.004649162, -0.004573822,
                        -0.004477024, -0.004357815, -0.004215240, -0.004049301, -0.003858566, -0.003643036, -0.003401756, 0.003134727,
                        0.002841473, 0.002521515, 0.002174854, 0.001800537, 0.001399517, 0.000971317, 0.000515938, 0.000033379,
                        -0.000475883, -0.001011848, -0.001573563, -0.002161503, -0.002774239, -0.003411293, -0.004072189, -0.004756451,
                        -0.005462170, -0.006189346, -0.006937027, -0.007703304, -0.008487225, -0.009287834, -0.010103703, -0.010933399,
                        -0.011775017, -0.012627602, -0.013489246, -0.014358521, -0.015233517, -0.016112804, -0.016994476, -0.017876148,
                        -0.018756866, -0.019634247, -0.020506859, -0.021372318, -0.022228718, -0.023074150, -0.023907185, -0.024725437,
                        -0.025527000, -0.026310921, -0.027073860, -0.027815342, -0.028532982, -0.029224873, -0.029890060, -0.030526638,
                        -0.031132698, -0.031706810, -0.032248020, -0.032754898, -0.033225536, -0.033659935, -0.034055710, -0.034412861,
                        -0.034730434, -0.035007000, -0.035242081, -0.035435200, -0.035586357, -0.035694122, -0.035758972, 0.035780907,
                        0.035758972, 0.035694122, 0.035586357, 0.035435200, 0.035242081, 0.035007000, 0.034730434, 0.034412861,
                        0.034055710, 0.033659935, 0.033225536, 0.032754898, 0.032248020, 0.031706810, 0.031132698, 0.030526638,
                        0.029890060, 0.029224873, 0.028532982, 0.027815342, 0.027073860, 0.026310921, 0.025527000, 0.024725437,
                        0.023907185, 0.023074150, 0.022228718, 0.021372318, 0.020506859, 0.019634247, 0.018756866, 0.017876148,
                        0.016994476, 0.016112804, 0.015233517, 0.014358521, 0.013489246, 0.012627602, 0.011775017, 0.010933399,
                        0.010103703, 0.009287834, 0.008487225, 0.007703304, 0.006937027, 0.006189346, 0.005462170, 0.004756451,
                        0.004072189, 0.003411293, 0.002774239, 0.002161503, 0.001573563, 0.001011848, 0.000475883, -0.000033379,
                        -0.000515938, -0.000971317, -0.001399517, -0.001800537, -0.002174854, -0.002521515, -0.002841473, 0.003134727,
                        0.003401756, 0.003643036, 0.003858566, 0.004049301, 0.004215240, 0.004357815, 0.004477024, 0.004573822,
                        0.004649162, 0.004703045, 0.004737377, 0.004752159, 0.004748821, 0.004728317, 0.004691124, 0.004638195,
                        0.004570484, 0.004489899, 0.004395962, 0.004290581, 0.004174709, 0.004048824, 0.003914356, 0.003771782,
                        0.003622532, 0.003467083, 0.003306866, 0.003141880, 0.002974033, 0.002803326, 0.002630711, 0.002457142,
                        0.002283096, 0.002110004, 0.001937389, 0.001766682, 0.001597881, 0.001432419, 0.001269817, 0.001111031,
                        0.000956535, 0.000806808, 0.000661850, 0.000522137, 0.000388145, 0.000259876, 0.000137329, 0.000021458,
                        -0.000088215, -0.000191689, -0.000288486, -0.000378609, -0.000462532, -0.000539303, -0.000610352, -0.000674248,
                        -0.000731945, -0.000783920, -0.000829220, -0.000868797, -0.000902653, -0.000930786, -0.000953674, 0.000971317,
                        0.000983715, 0.000991821, 0.000995159, 0.000994205, 0.000989437, 0.000980854, 0.000968933, 0.000954151,
                        0.000935555, 0.000915051, 0.000891685, 0.000866413, 0.000838757, 0.000809669, 0.000779152, 0.000747204,
                        0.000714302, 0.000680923, 0.000646591, 0.000611782, 0.000576973, 0.000542164, 0.000507355, 0.000472546,
                        0.000438213, 0.000404358, 0.000371456, 0.000339031, 0.000307560, 0.000277042, 0.000247478, 0.000218868,
                        0.000191212, 0.000165462, 0.000140190, 0.000116348, 0.000093937, 0.000072956, 0.000052929, 0.000034332,
                        0.000017166, 0.000000954, -0.000013828, -0.000027180, -0.000039577, -0.000050545, -0.000060558, -0.000069618,
                        -0.000077724, -0.000084400, -0.000090122, -0.000095367, -0.000099182, -0.000102520, -0.000105381, -0.000106812,
                        -0.000108242, -0.000108719, -0.000108719, -0.000108242, -0.000107288, -0.000105858, -0.000103951, 0.000101566,
                        0.000099182, 0.000096321, 0.000093460, 0.000090599, 0.000087261, 0.000083923, 0.000080585, 0.000076771,
                        0.000073433, 0.000070095, 0.000066280, 0.000062943, 0.000059605, 0.000055790, 0.000052929, 0.000049591,
                        0.000046253, 0.000043392, 0.000040531, 0.000037670, 0.000034809, 0.000032425, 0.000030041, 0.000027657,
                        0.000025272, 0.000023365, 0.000021458, 0.000019550, 0.000018120, 0.000016689, 0.000014782, 0.000013828,
                        0.000012398, 0.000011444, 0.000010014, 0.000009060, 0.000008106, 0.000007629, 0.000006676, 0.000006199,
                        0.000005245, 0.000004768, 0.000004292, 0.000003815, 0.000003338, 0.000003338, 0.000002861, 0.000002384,
                        0.000002384, 0.000001907, 0.000001907, 0.000001431, 0.000001431, 0.000000954, 0.000000954, 0.000000954,
                        0.000000954, 0.000000477, 0.000000477, 0.000000477, 0.000000477, 0.000000477, 0.000000477
                       };

static int scale_factor_table[64];
#ifdef USE_FLOATS
static float scale_factor_inv_table[64];
#else
static INT8 scale_factor_shift[64];
static unsigned short scale_factor_mult[64];
#endif
static unsigned char scale_diff_table[128];

static const int sblimit_table[5] = { 27 , 30 , 8, 12 , 30 };

static const int quant_steps[17] = {
    3,     5,    7,    9,    15,
    31,    63,  127,  255,   511,
    1023,  2047, 4095, 8191, 16383,
    32767, 65535
};

/* we use a negative value if grouped */
static const int quant_bits[17] = {
    -5,  -7,  3, -10, 4, 
     5,  6,  7,  8,  9,
    10, 11, 12, 13, 14,
    15, 16