rvoip-codec-core 0.3.8

//! Gain quantiser and math tables for AMR-WB, from the TS 26.173 reference.
//!
//! The math tables are AMR-WB's own. G.729 has tables for the same functions
//! with different values, and mixing them would give a codec that sounds
//! nearly right and fails conformance -- which is why these live here rather
//! than in the shared `fixed_point` module.
//!
//! Generated by `tools/gen_gain_tables.py`.

/// Gain codebook for the 6-bit modes.
///
/// 64 entries of (pitch gain Q14, code gain Q11). The two are quantised
/// jointly because they are strongly correlated -- a voiced frame wants
/// high pitch gain and low code gain, and coding them independently
/// would waste bits on combinations that never occur.
pub const QUA_GAIN_6B: [i16; 128] = [
    1566, 1332, 1577, 3557, 3071, 6490, 4193, 10163, 4496, 2534, 5019, 4488, 5586, 15614, 5725,
    1422, 6453, 580, 6724, 6831, 7657, 3527, 8072, 2099, 8232, 5319, 8827, 8775, 9740, 2868, 9856,
    1465, 10087, 12488, 10241, 4453, 10859, 6618, 11321, 3587, 11417, 1800, 11643, 2428, 11718,
    988, 12312, 5093, 12523, 8413, 12574, 26214, 12601, 3396, 13172, 1623, 13285, 2423, 13418,
    6087, 13459, 12810, 13656, 3607, 14111, 4521, 14144, 1229, 14425, 1871, 14431, 7234, 14445,
    2834, 14628, 10036, 14860, 17496, 15161, 3629, 15209, 5819, 15299, 2256, 15518, 4722, 15663,
    1060, 15759, 7972, 15939, 11964, 16020, 2996, 16086, 1707, 16521, 4254, 16576, 6224, 16894,
    2380, 16906, 681, 17213, 8406, 17610, 3418, 17895, 5269, 18168, 11748, 18230, 1575, 18607,
    32767, 18728, 21684, 19137, 2543, 19422, 6577, 19446, 4097, 19450, 9056, 20371, 14885,
];

/// Gain codebook for the 7-bit modes: 128 entries of (pitch gain Q14, code
/// gain Q11).
pub const QUA_GAIN_7B: [i16; 256] = [
    204, 441, 464, 1977, 869, 1077, 1072, 3062, 1281, 4759, 1647, 1539, 1845, 7020, 1853, 634,
    1995, 2336, 2351, 15400, 2661, 1165, 2702, 3900, 2710, 10133, 3195, 1752, 3498, 2624, 3663,
    849, 3984, 5697, 4214, 3399, 4415, 1304, 4695, 2056, 5376, 4558, 5386, 676, 5518, 23554, 5567,
    7794, 5644, 3061, 5672, 1513, 5957, 2338, 6533, 1060, 6804, 5998, 6820, 1767, 6937, 3837, 7277,
    414, 7305, 2665, 7466, 11304, 7942, 794, 8007, 1982, 8007, 1366, 8326, 3105, 8336, 4810, 8708,
    7954, 8989, 2279, 9031, 1055, 9247, 3568, 9283, 1631, 9654, 6311, 9811, 2605, 10120, 683,
    10143, 4179, 10245, 1946, 10335, 1218, 10468, 9960, 10651, 3000, 10951, 1530, 10969, 5290,
    11203, 2305, 11325, 3562, 11771, 6754, 11839, 1849, 11941, 4495, 11954, 1298, 11975, 15223,
    11977, 883, 11986, 2842, 12438, 2141, 12593, 3665, 12636, 8367, 12658, 1594, 12886, 2628,
    12984, 4942, 13146, 1115, 13224, 524, 13341, 3163, 13399, 1923, 13549, 5961, 13606, 1401,
    13655, 2399, 13782, 3909, 13868, 10923, 14226, 1723, 14232, 2939, 14278, 7528, 14439, 4598,
    14451, 984, 14458, 2265, 14792, 1403, 14818, 3445, 14899, 5709, 15017, 15362, 15048, 1946,
    15069, 2655, 15405, 9591, 15405, 4079, 15570, 7183, 15687, 2286, 15691, 1624, 15699, 3068,
    15772, 5149, 15868, 1205, 15970, 696, 16249, 3584, 16338, 1917, 16424, 2560, 16483, 4438,
    16529, 6410, 16620, 11966, 16839, 8780, 17030, 3050, 17033, 18325, 17092, 1568, 17123, 5197,
    17351, 2113, 17374, 980, 17566, 26214, 17609, 3912, 17639, 32767, 18151, 7871, 18197, 2516,
    18202, 5649, 18679, 3283, 18930, 1370, 19271, 13757, 19317, 4120, 19460, 1973, 19654, 10018,
    19764, 6792, 19912, 5135, 20040, 2841, 21234, 19833,
];

/// `1/sqrt(x)` sampled at 49 points, Q15, with linear interpolation between.
pub const ISQRT_TABLE: [i16; 49] = [
    32767, 31790, 30894, 30070, 29309, 28602, 27945, 27330, 26755, 26214, 25705, 25225, 24770,
    24339, 23930, 23541, 23170, 22817, 22479, 22155, 21845, 21548, 21263, 20988, 20724, 20470,
    20225, 19988, 19760, 19539, 19326, 19119, 18919, 18725, 18536, 18354, 18176, 18004, 17837,
    17674, 17515, 17361, 17211, 17064, 16921, 16782, 16646, 16514, 16384,
];

/// `2^x` over one octave, sampled at 33 points, Q15.
pub const POW2_TABLE: [i16; 33] = [
    16384, 16743, 17109, 17484, 17867, 18258, 18658, 19066, 19484, 19911, 20347, 20792, 21247,
    21713, 22188, 22674, 23170, 23678, 24196, 24726, 25268, 25821, 26386, 26964, 27554, 28158,
    28774, 29405, 30048, 30706, 31379, 32066, 32767,
];

/// `log2(x)` over one octave, sampled at 33 points, Q15.
pub const LOG2_TABLE: [i16; 33] = [
    0, 1455, 2866, 4236, 5568, 6863, 8124, 9352, 10549, 11716, 12855, 13967, 15054, 16117, 17156,
    18172, 19167, 20142, 21097, 22033, 22951, 23852, 24735, 25603, 26455, 27291, 28113, 28922,
    29716, 30497, 31266, 32023, 32767,
];

/// Band-pass for the synthesised high band, Q15 with a gain of 4.
///
/// Confines the noise to roughly 6-7 kHz. The name is the design band;
/// the input is pre-scaled by 1/4 to leave room for the filter's gain.
pub const FIR_6K_7K: [i16; 31] = [
    -32, 47, 32, -27, -369, 1122, -1421, 0, 3798, -8880, 12349, -10984, 3548, 7766, -18001, 22118,
    -18001, 7766, 3548, -10984, 12349, -8880, 3798, 0, -1421, 1122, -369, -27, 32, 47, -32,
];

/// Low-pass at 7 kHz, Q15. Applied only at 23.85 kbit/s, where the
/// transmitted high-band gains make the band loud enough for content
/// above 7 kHz to be audible.
pub const FIR_7K: [i16; 31] = [
    -21, 47, -89, 146, -203, 229, -177, 0, 335, -839, 1485, -2211, 2931, -3542, 3953, 28682, 3953,
    -3542, 2931, -2211, 1485, -839, 335, 0, -177, 229, -203, 146, -89, 47, -21,
];

/// High-band correction gains, Q14. Only 23.85 kbit/s transmits an index
/// into this; every other mode estimates the gain from the low band's
/// spectral tilt instead.
pub const HP_GAIN: [i16; 16] = [
    3624, 4673, 5597, 6479, 7425, 8378, 9324, 10264, 11210, 12206, 13391, 14844, 16770, 19655,
    24289, 32728,
];

/// Phase-dispersion impulse response, high dispersion, Q15.
///
/// Convolving the innovation with this spreads each pulse's energy over
/// time. At low rates there are too few pulses to sound like speech --
/// they read as clicks -- and smearing them trades peakiness for a more
/// noise-like excitation.
pub const PH_IMP_LOW: [i16; 64] = [
    20182, 9693, 3270, -3437, 2864, -5240, 1589, -1357, 600, 3893, -1497, -698, 1203, -5249, 1199,
    5371, -1488, -705, -2887, 1976, 898, 721, -3876, 4227, -5112, 6400, -1032, -4725, 4093, -4352,
    3205, 2130, -1996, -1835, 2648, -1786, -406, 573, 2484, -3608, 3139, -1363, -2566, 3808, -639,
    -2051, -541, 2376, 3932, -6262, 1432, -3601, 4889, 370, 567, -1163, -2854, 1914, 39, -2418,
    3454, 2975, -4021, 3431,
];

/// Phase-dispersion impulse response, moderate dispersion, Q15.
pub const PH_IMP_MID: [i16; 64] = [
    24098, 10460, -5263, -763, 2048, -927, 1753, -3323, 2212, 652, -2146, 2487, -3539, 4109, -2107,
    -374, -626, 4270, -5485, 2235, 1858, -2769, 744, 1140, -763, -1615, 4060, -4574, 2982, -1163,
    731, -1098, 803, 167, -714, 606, -560, 639, 43, -1766, 3228, -2782, 665, 763, 233, -2002, 1291,
    1871, -3470, 1032, 2710, -4040, 3624, -4214, 5292, -4270, 1563, 108, -580, 1642, -2458, 957,
    544, 2540,
];

/// Upsampling interpolation filter for 12.8 -> 16 kHz, Q14.
///
/// One fifth-sample resolution: 24 taps at each of five phases, stored
/// phase-interleaved. -1.5 dB at 6 kHz, -55 dB at 8 kHz -- steep, because
/// the 12.8 kHz signal has content right up to 6.4 kHz and anything above
/// it would alias into the band the high-band synthesis is about to fill.
pub const FIR_UP: [i16; 120] = [
    -1, -4, -7, -6, 0, 12, 24, 30, 23, 0, -33, -62, -73, -52, 0, 68, 124, 139, 96, 0, -119, -213,
    -235, -160, 0, 191, 338, 368, 247, 0, -291, -510, -552, -369, 0, 430, 752, 812, 542, 0, -634,
    -1111, -1204, -809, 0, 963, 1708, 1881, 1288, 0, -1616, -2974, -3432, -2496, 0, 3792, 8219,
    12368, 15317, 16384, 15317, 12368, 8219, 3792, 0, -2496, -3432, -2974, -1616, 0, 1288, 1881,
    1708, 963, 0, -809, -1204, -1111, -634, 0, 542, 812, 752, 430, 0, -369, -552, -510, -291, 0,
    247, 368, 338, 191, 0, -160, -235, -213, -119, 0, 96, 139, 124, 68, 0, -52, -73, -62, -33, 0,
    23, 30, 24, 12, 0, -6, -7, -4, -1, 0,
];