FreeCalypso > hg > gsm-codec-lib
view libtwamr/c2_11pf.c @ 492:cc3a831712a4
libgsmhr1: implement arbitrary RTP input
author | Mychaela Falconia <falcon@freecalypso.org> |
---|---|
date | Sat, 15 Jun 2024 06:52:37 +0000 |
parents | 9bca350be398 |
children |
line wrap: on
line source
/* ***************************************************************************** * * GSM AMR-NB speech codec R98 Version 7.6.0 December 12, 2001 * R99 Version 3.3.0 * REL-4 Version 4.1.0 * ***************************************************************************** * * File : c2_11pf.c * Purpose : Searches a 11 bit algebraic codebook containing 2 pulses * in a frame of 40 samples. * ***************************************************************************** */ /* ***************************************************************************** * MODULE INCLUDE FILE AND VERSION ID ***************************************************************************** */ #include "namespace.h" #include "c2_11pf.h" /* ***************************************************************************** * INCLUDE FILES ***************************************************************************** */ #include "typedef.h" #include "basic_op.h" #include "no_count.h" #include "inv_sqrt.h" #include "cnst.h" #include "cor_h.h" #include "set_sign.h" /* ***************************************************************************** * LOCAL VARIABLES AND TABLES ***************************************************************************** */ #define NB_PULSE 2 #include "c2_11pf.tab" /* ***************************************************************************** * DECLARATION OF PROTOTYPES ***************************************************************************** */ static void search_2i40( Word16 dn[], /* i : correlation between target and h[] */ Word16 rr[][L_CODE],/* i : matrix of autocorrelation */ Word16 codvec[] /* o : algebraic codebook vector */ ); static Word16 build_code( Word16 codvec[], /* i : algebraic codebook vector */ Word16 dn_sign[], /* i : sign of dn[] */ Word16 cod[], /* o : algebraic (fixed) codebook excitation */ Word16 h[], /* i : impulse response of weighted synthesis filter */ Word16 y[], /* o : filtered fixed codebook excitation */ Word16 sign[] /* o : sign of 2 pulses */ ); /* ***************************************************************************** * PUBLIC PROGRAM CODE ***************************************************************************** */ /************************************************************************* * * FUNCTION: code_2i40_11bits() * * PURPOSE: Searches a 11 bit algebraic codebook containing 2 pulses * in a frame of 40 samples. * * DESCRIPTION: * The code length is 40, containing 2 nonzero pulses: i0...i1. * All pulses can have two possible amplitudes: +1 or -1. * Pulse i0 can have 2x8=16 possible positions, pulse i1 can have * 4x8=32 positions. * * i0 : 1, 6, 11, 16, 21, 26, 31, 36. * 3, 8, 13, 18, 23, 28, 33, 38. * i1 : 0, 5, 10, 15, 20, 25, 30, 35. * 1, 6, 11, 16, 21, 26, 31, 36. * 2, 7, 12, 17, 22, 27, 32, 37. * 4, 9, 14, 19, 24, 29, 34, 39. * *************************************************************************/ Word16 code_2i40_11bits( Word16 x[], /* i : target vector */ Word16 h[], /* i : impulse response of weighted synthesis filter */ /* h[-L_subfr..-1] must be set to zero. */ Word16 T0, /* i : Pitch lag */ Word16 pitch_sharp, /* i : Last quantized pitch gain */ Word16 code[], /* o : Innovative codebook */ Word16 y[], /* o : filtered fixed codebook excitation */ Word16 * sign /* o : Signs of 2 pulses */ ) { Word16 codvec[NB_PULSE]; Word16 dn[L_CODE], dn2[L_CODE], dn_sign[L_CODE]; Word16 rr[L_CODE][L_CODE]; Word16 i, index, sharp; sharp = shl(pitch_sharp, 1); test (); if (sub(T0, L_CODE) < 0) { for (i = T0; i < L_CODE; i++) { h[i] = add(h[i], mult(h[i - T0], sharp)); move16 (); } } cor_h_x(h, x, dn, 1); set_sign(dn, dn_sign, dn2, 8); /* dn2[] not used in this codebook search */ cor_h(h, dn_sign, rr); search_2i40(dn, rr, codvec); move16 (); /* function result */ index = build_code(codvec, dn_sign, code, h, y, sign); /*-----------------------------------------------------------------* * Compute innovation vector gain. * * Include fixed-gain pitch contribution into code[]. * *-----------------------------------------------------------------*/ test (); if (sub(T0, L_CODE) < 0) { for (i = T0; i < L_CODE; i++) { code[i] = add(code[i], mult(code[i - T0], sharp)); move16 (); } } return index; } /* ***************************************************************************** * PRIVATE PROGRAM CODE ***************************************************************************** */ /************************************************************************* * * FUNCTION search_2i40() * * PURPOSE: Search the best codevector; determine positions of the 2 pulses * in the 40-sample frame. * *************************************************************************/ #define _1_2 (Word16)(32768L/2) #define _1_4 (Word16)(32768L/4) #define _1_8 (Word16)(32768L/8) #define _1_16 (Word16)(32768L/16) static void search_2i40( Word16 dn[], /* i : correlation between target and h[] */ Word16 rr[][L_CODE], /* i : matrix of autocorrelation */ Word16 codvec[] /* o : algebraic codebook vector */ ) { Word16 i0, i1; Word16 ix = 0; /* initialization only needed to keep gcc silent */ Word16 track1, track2, ipos[NB_PULSE]; Word16 psk, ps0, ps1, sq, sq1; Word16 alpk, alp, alp_16; Word32 s, alp0, alp1; Word16 i; psk = -1; move16 (); alpk = 1; move16 (); for (i = 0; i < NB_PULSE; i++) { codvec[i] = i; move16 (); } /*------------------------------------------------------------------* * main loop: try 2x4 tracks. * *------------------------------------------------------------------*/ for (track1 = 0; track1 < 2; track1++) { for (track2 = 0; track2 < 4; track2++) { /* fix starting position */ ipos[0] = startPos1[track1]; move16 (); ipos[1] = startPos2[track2]; move16 (); /*----------------------------------------------------------------* * i0 loop: try 8 positions. * *----------------------------------------------------------------*/ move16 (); /* account for ptr. init. (rr[io]) */ for (i0 = ipos[0]; i0 < L_CODE; i0 += STEP) { ps0 = dn[i0]; move16 (); alp0 = L_mult(rr[i0][i0], _1_4); /*-------------------------------------------------------------* * i1 loop: 8 positions. * *-------------------------------------------------------------*/ sq = -1; move16 (); alp = 1; move16 (); ix = ipos[1]; move16 (); /*---------------------------------------------------------------* * These index have low complexity address computation because * * they are, in fact, pointers with fixed increment. For example,* * "rr[i0][i2]" is a pointer initialized to "&rr[i0][ipos[2]]" * * and incremented by "STEP". * *---------------------------------------------------------------*/ move16 (); /* account for ptr. init. (rr[i1]) */ move16 (); /* account for ptr. init. (dn[i1]) */ move16 (); /* account for ptr. init. (rr[io]) */ for (i1 = ipos[1]; i1 < L_CODE; i1 += STEP) { ps1 = add(ps0, dn[i1]); /* idx increment = STEP */ /* alp1 = alp0 + rr[i0][i1] + 1/2*rr[i1][i1]; */ alp1 = L_mac(alp0, rr[i1][i1], _1_4); /* idx incr = STEP */ alp1 = L_mac(alp1, rr[i0][i1], _1_2); /* idx incr = STEP */ sq1 = mult(ps1, ps1); alp_16 = round(alp1); s = L_msu(L_mult(alp, sq1), sq, alp_16); test (); if (s > 0) { sq = sq1; move16 (); alp = alp_16; move16 (); ix = i1; move16 (); } } /*---------------------------------------------------------------* * memorise codevector if this one is better than the last one. * *---------------------------------------------------------------*/ s = L_msu(L_mult(alpk, sq), psk, alp); test (); if (s > 0) { psk = sq; move16 (); alpk = alp; move16 (); codvec[0] = i0; move16 (); codvec[1] = ix; move16 (); } } } } return; } /************************************************************************* * * FUNCTION: build_code() * * PURPOSE: Builds the codeword, the filtered codeword and index of the * codevector, based on the signs and positions of 2 pulses. * *************************************************************************/ static Word16 build_code( Word16 codvec[], /* i : position of pulses */ Word16 dn_sign[], /* i : sign of pulses */ Word16 cod[], /* o : innovative code vector */ Word16 h[], /* i : impulse response of weighted synthesis filter */ Word16 y[], /* o : filtered innovative code */ Word16 sign[] /* o : sign of 2 pulses */ ) { Word16 i, j, k, track, index, _sign[NB_PULSE], indx, rsign; Word16 *p0, *p1; Word32 s; for (i = 0; i < L_CODE; i++) { cod[i] = 0; move16 (); } indx = 0; move16 (); rsign = 0; move16 (); for (k = 0; k < NB_PULSE; k++) { i = codvec[k]; /* read pulse position */ move16 (); j = dn_sign[i]; /* read sign */ move16 (); index = mult(i, 6554); /* index = pos/5 */ /* track = pos%5 */ track = sub(i, extract_l(L_shr(L_mult(index, 5), 1))); test (); test (); test (); test (); if (sub(track, 0) == 0) { track = 1; move16 (); index = shl(index, 6); } else if (sub(track, 1) == 0) { test (); if (sub(k, 0) == 0) { track = 0; move16 (); index = shl(index, 1); } else { track = 1; move16 (); index = add(shl(index, 6), 16); } } else if (sub(track, 2) == 0) { track = 1; move16 (); index = add(shl(index, 6), 32); } else if (sub(track, 3) == 0) { track = 0; move16 (); index = add(shl(index, 1), 1); } else if (sub(track, 4) == 0) { track = 1; move16 (); index = add(shl(index, 6), 48); } test (); if (j > 0) { cod[i] = 8191; move16 (); _sign[k] = 32767; move16 (); rsign = add(rsign, shl(1, track)); } else { cod[i] = -8192; move16 (); _sign[k] = (Word16) - 32768L; move16 (); } indx = add(indx, index); } *sign = rsign; move16 (); p0 = h - codvec[0]; move16 (); p1 = h - codvec[1]; move16 (); for (i = 0; i < L_CODE; i++) { s = 0; move32 (); s = L_mac(s, *p0++, _sign[0]); s = L_mac(s, *p1++, _sign[1]); y[i] = round(s); move16 (); } return indx; }