ref: aa3a599caa2aa2e4f3036eb0e3b848bf3946821e
dir: /silk/resampler_rom.c/
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#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
/* Filter coefficients for IIR/FIR polyphase resampling *
* Total size: 179 Words (358 Bytes) */
#include "resampler_private.h"
/* Matlab code for the notch filter coefficients: */
/* B = [1, 0.147, 1]; A = [1, 0.107, 0.89]; G = 0.93; freqz(G * B, A, 2^14, 16e3); axis([0, 8000, -10, 1]) */
/* fprintf('\t%6d, %6d, %6d, %6d\n', round(B(2)*2^16), round(-A(2)*2^16), round((1-A(3))*2^16), round(G*2^15)) */
/* const opus_int16 silk_resampler_up2_hq_notch[ 4 ] = { 9634, -7012, 7209, 30474 }; */
/* Tables with IIR and FIR coefficients for fractional downsamplers (123 Words) */
silk_DWORD_ALIGN const opus_int16 silk_Resampler_3_4_COEFS[ 2 + 3 * RESAMPLER_DOWN_ORDER_FIR0 / 2 ] = {
-20694, -13867,
-49, 64, 17, -157, 353, -496, 163, 11047, 22205,
-39, 6, 91, -170, 186, 23, -896, 6336, 19928,
-19, -36, 102, -89, -24, 328, -951, 2568, 15909,
};
silk_DWORD_ALIGN const opus_int16 silk_Resampler_2_3_COEFS[ 2 + 2 * RESAMPLER_DOWN_ORDER_FIR0 / 2 ] = {
-14457, -14019,
64, 128, -122, 36, 310, -768, 584, 9267, 17733,
12, 128, 18, -142, 288, -117, -865, 4123, 14459,
};
silk_DWORD_ALIGN const opus_int16 silk_Resampler_1_2_COEFS[ 2 + RESAMPLER_DOWN_ORDER_FIR1 / 2 ] = {
616, -14323,
-10, 39, 58, -46, -84, 120, 184, -315, -541, 1284, 5380, 9024,
};
silk_DWORD_ALIGN const opus_int16 silk_Resampler_1_3_COEFS[ 2 + RESAMPLER_DOWN_ORDER_FIR2 / 2 ] = {
16102, -15162,
-13, 0, 20, 26, 5, -31, -43, -4, 65, 90, 7, -157, -248, -44, 593, 1583, 2612, 3271,
};
silk_DWORD_ALIGN const opus_int16 silk_Resampler_1_4_COEFS[ 2 + RESAMPLER_DOWN_ORDER_FIR2 / 2 ] = {
22500, -15099,
3, -14, -20, -15, 2, 25, 37, 25, -16, -71, -107, -79, 50, 292, 623, 982, 1288, 1464,
};
silk_DWORD_ALIGN const opus_int16 silk_Resampler_1_6_COEFS[ 2 + RESAMPLER_DOWN_ORDER_FIR2 / 2 ] = {
27540, -15257,
17, 12, 8, 1, -10, -22, -30, -32, -22, 3, 44, 100, 168, 243, 317, 381, 429, 455,
};
silk_DWORD_ALIGN const opus_int16 silk_Resampler_2_3_COEFS_LQ[ 2 + 2 * 2 ] = {
-2797, -6507,
4697, 10739,
1567, 8276,
};
/* Table with interplation fractions of 1/24, 3/24, 5/24, ... , 23/24 : 23/24 (46 Words) */
silk_DWORD_ALIGN const opus_int16 silk_resampler_frac_FIR_12[ 12 ][ RESAMPLER_ORDER_FIR_12 / 2 ] = {
{ 189, -600, 617, 30567 },
{ 117, -159, -1070, 29704 },
{ 52, 221, -2392, 28276 },
{ -4, 529, -3350, 26341 },
{ -48, 758, -3956, 23973 },
{ -80, 905, -4235, 21254 },
{ -99, 972, -4222, 18278 },
{ -107, 967, -3957, 15143 },
{ -103, 896, -3487, 11950 },
{ -91, 773, -2865, 8798 },
{ -71, 611, -2143, 5784 },
{ -46, 425, -1375, 2996 },
};