ref: 682066657d61167c6cbe4d06b392699947b39d2d
dir: /amr-wb/c4t64fx.c/
/*------------------------------------------------------------------------* * C4T64FX.C * *------------------------------------------------------------------------* * Performs algebraic codebook search for higher modes * *------------------------------------------------------------------------*/ /*-----------------------------------------------------------------------* * Function ACELP_4t64_fx() * * ~~~~~~~~~~~~~~~~~~~~~~~~~ * * 20, 36, 44, 52, 64, 72, 88 bits algebraic codebook. * * 4 tracks x 16 positions per track = 64 samples. * * * * 20 bits --> 4 pulses in a frame of 64 samples. * * 36 bits --> 8 pulses in a frame of 64 samples. * * 44 bits --> 10 pulses in a frame of 64 samples. * * 52 bits --> 12 pulses in a frame of 64 samples. * * 64 bits --> 16 pulses in a frame of 64 samples. * * 72 bits --> 18 pulses in a frame of 64 samples. * * 88 bits --> 24 pulses in a frame of 64 samples. * * * * All pulses can have two (2) possible amplitudes: +1 or -1. * * Each pulse can have sixteen (16) possible positions. * *-----------------------------------------------------------------------*/ #include "typedef.h" #include "basic_op.h" #include "math_op.h" #include "acelp.h" #include "count.h" #include "cnst.h" #include "q_pulse.h" static Word16 tipos[36] = { 0, 1, 2, 3, /* starting point &ipos[0], 1st iter */ 1, 2, 3, 0, /* starting point &ipos[4], 2nd iter */ 2, 3, 0, 1, /* starting point &ipos[8], 3rd iter */ 3, 0, 1, 2, /* starting point &ipos[12], 4th iter */ 0, 1, 2, 3, 1, 2, 3, 0, 2, 3, 0, 1, 3, 0, 1, 2, 0, 1, 2, 3}; /* end point for 24 pulses &ipos[35], 4th iter */ #define NB_PULSE_MAX 24 #define L_SUBFR 64 #define NB_TRACK 4 #define STEP 4 #define NB_POS 16 #define MSIZE 256 #define NB_MAX 8 #define NPMAXPT ((NB_PULSE_MAX+NB_TRACK-1)/NB_TRACK) /* locals functions */ static void cor_h_vec( Word16 h[], /* (i) scaled impulse response */ Word16 vec[], /* (i) scaled vector (/8) to correlate with h[] */ Word16 track, /* (i) track to use */ Word16 sign[], /* (i) sign vector */ Word16 rrixix[][NB_POS], /* (i) correlation of h[x] with h[x] */ Word16 cor[] /* (o) result of correlation (NB_POS elements) */ ); static void search_ixiy( Word16 nb_pos_ix, /* (i) nb of pos for pulse 1 (1..8) */ Word16 track_x, /* (i) track of pulse 1 */ Word16 track_y, /* (i) track of pulse 2 */ Word16 * ps, /* (i/o) correlation of all fixed pulses */ Word16 * alp, /* (i/o) energy of all fixed pulses */ Word16 * ix, /* (o) position of pulse 1 */ Word16 * iy, /* (o) position of pulse 2 */ Word16 dn[], /* (i) corr. between target and h[] */ Word16 dn2[], /* (i) vector of selected positions */ Word16 cor_x[], /* (i) corr. of pulse 1 with fixed pulses */ Word16 cor_y[], /* (i) corr. of pulse 2 with fixed pulses */ Word16 rrixiy[][MSIZE] /* (i) corr. of pulse 1 with pulse 2 */ ); void ACELP_4t64_fx( Word16 dn[], /* (i) <12b : correlation between target x[] and H[] */ Word16 cn[], /* (i) <12b : residual after long term prediction */ Word16 H[], /* (i) Q12: impulse response of weighted synthesis filter */ Word16 code[], /* (o) Q9 : algebraic (fixed) codebook excitation */ Word16 y[], /* (o) Q9 : filtered fixed codebook excitation */ Word16 nbbits, /* (i) : 20, 36, 44, 52, 64, 72 or 88 bits */ Word16 ser_size, /* (i) : bit rate */ Word16 _index[] /* (o) : index (20): 5+5+5+5 = 20 bits. */ /* (o) : index (36): 9+9+9+9 = 36 bits. */ /* (o) : index (44): 13+9+13+9 = 44 bits. */ /* (o) : index (52): 13+13+13+13 = 52 bits. */ /* (o) : index (64): 2+2+2+2+14+14+14+14 = 64 bits. */ /* (o) : index (72): 10+2+10+2+10+14+10+14 = 72 bits. */ /* (o) : index (88): 11+11+11+11+11+11+11+11 = 88 bits. */ ) { Word16 i, j, k, st, ix = 0, iy = 0, pos, index, track, nb_pulse, nbiter; Word16 psk, ps, alpk, alp, val, k_cn, k_dn, exp; Word16 *p0, *p1, *p2, *p3, *psign; Word16 *h, *h_inv, *ptr_h1, *ptr_h2, *ptr_hf, h_shift; Word32 s, cor, L_tmp, L_index; Word16 dn2[L_SUBFR], sign[L_SUBFR], vec[L_SUBFR]; Word16 ind[NPMAXPT * NB_TRACK]; Word16 codvec[NB_PULSE_MAX], nbpos[10]; Word16 cor_x[NB_POS], cor_y[NB_POS], pos_max[NB_TRACK]; Word16 h_buf[4 * L_SUBFR]; Word16 rrixix[NB_TRACK][NB_POS], rrixiy[NB_TRACK][MSIZE]; Word16 ipos[NB_PULSE_MAX]; switch (nbbits) { case 20: /* 20 bits, 4 pulses, 4 tracks */ nbiter = 4; move16(); /* 4x16x16=1024 loop */ alp = 8192; move16(); /* alp = 2.0 (Q12) */ nb_pulse = 4; move16(); nbpos[0] = 4; move16(); nbpos[1] = 8; move16(); break; case 36: /* 36 bits, 8 pulses, 4 tracks */ nbiter = 4; move16(); /* 4x20x16=1280 loop */ alp = 4096; move16(); /* alp = 1.0 (Q12) */ nb_pulse = 8; move16(); nbpos[0] = 4; move16(); nbpos[1] = 8; move16(); nbpos[2] = 8; move16(); break; case 44: /* 44 bits, 10 pulses, 4 tracks */ nbiter = 4; move16(); /* 4x26x16=1664 loop */ alp = 4096; move16(); /* alp = 1.0 (Q12) */ nb_pulse = 10; move16(); nbpos[0] = 4; move16(); nbpos[1] = 6; move16(); nbpos[2] = 8; move16(); nbpos[3] = 8; move16(); break; case 52: /* 52 bits, 12 pulses, 4 tracks */ nbiter = 4; move16(); /* 4x26x16=1664 loop */ alp = 4096; move16(); /* alp = 1.0 (Q12) */ nb_pulse = 12; move16(); nbpos[0] = 4; move16(); nbpos[1] = 6; move16(); nbpos[2] = 8; move16(); nbpos[3] = 8; move16(); break; case 64: /* 64 bits, 16 pulses, 4 tracks */ nbiter = 3; move16(); /* 3x36x16=1728 loop */ alp = 3277; move16(); /* alp = 0.8 (Q12) */ nb_pulse = 16; move16(); nbpos[0] = 4; move16(); nbpos[1] = 4; move16(); nbpos[2] = 6; move16(); nbpos[3] = 6; move16(); nbpos[4] = 8; move16(); nbpos[5] = 8; move16(); break; case 72: /* 72 bits, 18 pulses, 4 tracks */ nbiter = 3; move16(); /* 3x35x16=1680 loop */ alp = 3072; move16(); /* alp = 0.75 (Q12) */ nb_pulse = 18; move16(); nbpos[0] = 2; move16(); nbpos[1] = 3; move16(); nbpos[2] = 4; move16(); nbpos[3] = 5; move16(); nbpos[4] = 6; move16(); nbpos[5] = 7; move16(); nbpos[6] = 8; move16(); break; case 88: /* 88 bits, 24 pulses, 4 tracks */ test();move16(); if (sub(ser_size, 462) > 0) nbiter = 1; else nbiter = 2; /* 2x53x16=1696 loop */ alp = 2048; move16(); /* alp = 0.5 (Q12) */ nb_pulse = 24; move16(); nbpos[0] = 2; move16(); nbpos[1] = 2; move16(); nbpos[2] = 3; move16(); nbpos[3] = 4; move16(); nbpos[4] = 5; move16(); nbpos[5] = 6; move16(); nbpos[6] = 7; move16(); nbpos[7] = 8; move16(); nbpos[8] = 8; move16(); nbpos[9] = 8; move16(); break; default: nbiter = 0; alp = 0; nb_pulse = 0; } for (i = 0; i < nb_pulse; i++) { codvec[i] = i; move16(); } /*----------------------------------------------------------------* * Find sign for each pulse position. * *----------------------------------------------------------------*/ /* calculate energy for normalization of cn[] and dn[] */ /* set k_cn = 32..32767 (ener_cn = 2^30..256-0) */ s = Dot_product12(cn, cn, L_SUBFR, &exp); Isqrt_n(&s, &exp); s = L_shl(s, add(exp, 5)); /* saturation can occur here */ k_cn = roundL(s); /* set k_dn = 32..512 (ener_dn = 2^30..2^22) */ s = Dot_product12(dn, dn, L_SUBFR, &exp); Isqrt_n(&s, &exp); k_dn = roundL(L_shl(s, add(exp, 5 + 3))); /* k_dn = 256..4096 */ k_dn = mult_r(alp, k_dn); /* alp in Q12 */ /* mix normalized cn[] and dn[] */ for (i = 0; i < L_SUBFR; i++) { s = L_mac(L_mult(k_cn, cn[i]), k_dn, dn[i]); dn2[i] = extract_h(L_shl(s, 8)); move16(); } /* set sign according to dn2[] = k_cn*cn[] + k_dn*dn[] */ for (k = 0; k < NB_TRACK; k++) { for (i = k; i < L_SUBFR; i += STEP) { val = dn[i]; move16(); ps = dn2[i]; move16(); test(); if (ps >= 0) { sign[i] = 32767; move16(); /* sign = +1 (Q12) */ vec[i] = -32768; move16(); } else { sign[i] = -32768; move16(); /* sign = -1 (Q12) */ vec[i] = 32767; move16(); val = negate(val); ps = negate(ps); } dn[i] = val; move16(); /* modify dn[] according to the fixed sign */ dn2[i] = ps; move16(); /* dn2[] = mix of dn[] and cn[] */ } } /*----------------------------------------------------------------* * Select NB_MAX position per track according to max of dn2[]. * *----------------------------------------------------------------*/ pos = 0; for (i = 0; i < NB_TRACK; i++) { for (k = 0; k < NB_MAX; k++) { ps = -1; move16(); for (j = i; j < L_SUBFR; j += STEP) { test(); if (sub(dn2[j], ps) > 0) { ps = dn2[j]; move16(); pos = j; move16(); } } move16(); dn2[pos] = sub(k, NB_MAX); /* dn2 < 0 when position is selected */ test(); if (k == 0) { pos_max[i] = pos; move16(); } } } /*--------------------------------------------------------------* * Scale h[] to avoid overflow and to get maximum of precision * * on correlation. * * * * Maximum of h[] (h[0]) is fixed to 2048 (MAX16 / 16). * * ==> This allow addition of 16 pulses without saturation. * * * * Energy worst case (on resonant impulse response), * * - energy of h[] is approximately MAX/16. * * - During search, the energy is divided by 8 to avoid * * overflow on "alp". (energy of h[] = MAX/128). * * ==> "alp" worst case detected is 22854 on sinusoidal wave. * *--------------------------------------------------------------*/ /* impulse response buffer for fast computation */ h = h_buf; move16(); h_inv = h_buf + (2 * L_SUBFR); move16(); for (i = 0; i < L_SUBFR; i++) { *h++ = 0; move16(); *h_inv++ = 0; move16(); } /* scale h[] down (/2) when energy of h[] is high with many pulses used */ L_tmp = 0; for (i = 0; i < L_SUBFR; i++) L_tmp = L_mac(L_tmp, H[i], H[i]); val = extract_h(L_tmp); h_shift = 0; move16(); test();test(); if ((sub(nb_pulse, 12) >= 0) && (sub(val, 1024) > 0)) { h_shift = 1; move16(); } for (i = 0; i < L_SUBFR; i++) { h[i] = shr(H[i], h_shift); move16(); h_inv[i] = negate(h[i]); move16(); } /*------------------------------------------------------------* * Compute rrixix[][] needed for the codebook search. * * This algorithm compute impulse response energy of all * * positions (16) in each track (4). Total = 4x16 = 64. * *------------------------------------------------------------*/ /* storage order --> i3i3, i2i2, i1i1, i0i0 */ /* Init pointers to last position of rrixix[] */ p0 = &rrixix[0][NB_POS - 1]; move16(); p1 = &rrixix[1][NB_POS - 1]; move16(); p2 = &rrixix[2][NB_POS - 1]; move16(); p3 = &rrixix[3][NB_POS - 1]; move16(); ptr_h1 = h; move16(); cor = 0x00008000L; move32(); /* for rounding */ for (i = 0; i < NB_POS; i++) { cor = L_mac(cor, *ptr_h1, *ptr_h1); ptr_h1++; *p3-- = extract_h(cor); move16(); cor = L_mac(cor, *ptr_h1, *ptr_h1); ptr_h1++; *p2-- = extract_h(cor); move16(); cor = L_mac(cor, *ptr_h1, *ptr_h1); ptr_h1++; *p1-- = extract_h(cor); move16(); cor = L_mac(cor, *ptr_h1, *ptr_h1); ptr_h1++; *p0-- = extract_h(cor); move16(); } /*------------------------------------------------------------* * Compute rrixiy[][] needed for the codebook search. * * This algorithm compute correlation between 2 pulses * * (2 impulses responses) in 4 possible adjacents tracks. * * (track 0-1, 1-2, 2-3 and 3-0). Total = 4x16x16 = 1024. * *------------------------------------------------------------*/ /* storage order --> i2i3, i1i2, i0i1, i3i0 */ pos = MSIZE - 1; move16(); ptr_hf = h + 1; move16(); for (k = 0; k < NB_POS; k++) { p3 = &rrixiy[2][pos]; move16(); p2 = &rrixiy[1][pos]; move16(); p1 = &rrixiy[0][pos]; move16(); p0 = &rrixiy[3][pos - NB_POS]; move16(); cor = 0x00008000L; move32(); /* for rounding */ ptr_h1 = h; move16(); ptr_h2 = ptr_hf; move16(); for (i = add(k, 1); i < NB_POS; i++) { cor = L_mac(cor, *ptr_h1, *ptr_h2); ptr_h1++; ptr_h2++; *p3 = extract_h(cor); move16(); cor = L_mac(cor, *ptr_h1, *ptr_h2); ptr_h1++; ptr_h2++; *p2 = extract_h(cor); move16(); cor = L_mac(cor, *ptr_h1, *ptr_h2); ptr_h1++; ptr_h2++; *p1 = extract_h(cor); move16(); cor = L_mac(cor, *ptr_h1, *ptr_h2); ptr_h1++; ptr_h2++; *p0 = extract_h(cor); move16(); p3 -= (NB_POS + 1); p2 -= (NB_POS + 1); p1 -= (NB_POS + 1); p0 -= (NB_POS + 1); } cor = L_mac(cor, *ptr_h1, *ptr_h2); ptr_h1++; ptr_h2++; *p3 = extract_h(cor); move16(); cor = L_mac(cor, *ptr_h1, *ptr_h2); ptr_h1++; ptr_h2++; *p2 = extract_h(cor); move16(); cor = L_mac(cor, *ptr_h1, *ptr_h2); ptr_h1++; ptr_h2++; *p1 = extract_h(cor); move16(); pos -= NB_POS; ptr_hf += STEP; } /* storage order --> i3i0, i2i3, i1i2, i0i1 */ pos = MSIZE - 1; move16(); ptr_hf = h + 3; move16(); for (k = 0; k < NB_POS; k++) { p3 = &rrixiy[3][pos]; move16(); p2 = &rrixiy[2][pos - 1]; move16(); p1 = &rrixiy[1][pos - 1]; move16(); p0 = &rrixiy[0][pos - 1]; move16(); cor = 0x00008000L; move32(); /* for rounding */ ptr_h1 = h; move16(); ptr_h2 = ptr_hf; move16(); for (i = add(k, 1); i < NB_POS; i++) { cor = L_mac(cor, *ptr_h1, *ptr_h2); ptr_h1++; ptr_h2++; *p3 = extract_h(cor); move16(); cor = L_mac(cor, *ptr_h1, *ptr_h2); ptr_h1++; ptr_h2++; *p2 = extract_h(cor); move16(); cor = L_mac(cor, *ptr_h1, *ptr_h2); ptr_h1++; ptr_h2++; *p1 = extract_h(cor); move16(); cor = L_mac(cor, *ptr_h1, *ptr_h2); ptr_h1++; ptr_h2++; *p0 = extract_h(cor); move16(); p3 -= (NB_POS + 1); p2 -= (NB_POS + 1); p1 -= (NB_POS + 1); p0 -= (NB_POS + 1); } cor = L_mac(cor, *ptr_h1, *ptr_h2); ptr_h1++; ptr_h2++; *p3 = extract_h(cor); move16(); pos--; ptr_hf += STEP; } /*------------------------------------------------------------* * Modification of rrixiy[][] to take signs into account. * *------------------------------------------------------------*/ p0 = &rrixiy[0][0]; move16(); for (k = 0; k < NB_TRACK; k++) { for (i = k; i < L_SUBFR; i += STEP) { psign = sign; move16(); test(); if (psign[i] < 0) { psign = vec; move16(); } for (j = (Word16) ((k + 1) % NB_TRACK); j < L_SUBFR; j += STEP) { *p0 = mult(*p0, psign[j]); move16(); p0++; } } } /*-------------------------------------------------------------------* * Deep first search * *-------------------------------------------------------------------*/ psk = -1; move16(); alpk = 1; move16(); for (k = 0; k < nbiter; k++) { for (i = 0; i < nb_pulse; i++) ipos[i] = tipos[(k * 4) + i]; test();test();test(); if (sub(nbbits, 20) == 0) { pos = 0; move16(); ps = 0; move16(); alp = 0; move16(); for (i = 0; i < L_SUBFR; i++) { vec[i] = 0; move16(); } } else if ((sub(nbbits, 36) == 0) || (sub(nbbits, 44) == 0)) { /* first stage: fix 2 pulses */ pos = 2; ix = ind[0] = pos_max[ipos[0]];move16();move16(); iy = ind[1] = pos_max[ipos[1]];move16();move16(); ps = add(dn[ix], dn[iy]); i = shr(ix, 2); /* ix / STEP */ j = shr(iy, 2); /* iy / STEP */ s = L_mult(rrixix[ipos[0]][i], 4096); s = L_mac(s, rrixix[ipos[1]][j], 4096); i = add(shl(i, 4), j); /* (ix/STEP)*NB_POS + (iy/STEP) */ s = L_mac(s, rrixiy[ipos[0]][i], 8192); alp = roundL(s); test();move16();move16(); if (sign[ix] < 0) p0 = h_inv - ix; else p0 = h - ix; test();move16();move16(); if (sign[iy] < 0) p1 = h_inv - iy; else p1 = h - iy; for (i = 0; i < L_SUBFR; i++) { vec[i] = add(*p0++, *p1++);move16(); } test(); if (sub(nbbits, 44) == 0) { ipos[8] = 0; move16(); ipos[9] = 1; move16(); } } else { /* first stage: fix 4 pulses */ pos = 4; ix = ind[0] = pos_max[ipos[0]]; move16();move16(); iy = ind[1] = pos_max[ipos[1]]; move16();move16(); i = ind[2] = pos_max[ipos[2]]; move16();move16(); j = ind[3] = pos_max[ipos[3]]; move16();move16(); ps = add(add(add(dn[ix], dn[iy]), dn[i]), dn[j]); test();move16();move16(); if (sign[ix] < 0) p0 = h_inv - ix; else p0 = h - ix; test();move16();move16(); if (sign[iy] < 0) p1 = h_inv - iy; else p1 = h - iy; test();move16();move16(); if (sign[i] < 0) p2 = h_inv - i; else p2 = h - i; test();move16();move16(); if (sign[j] < 0) p3 = h_inv - j; else p3 = h - j; for (i = 0; i < L_SUBFR; i++) { vec[i] = add(add(add(*p0++, *p1++), *p2++), *p3++); move16(); } L_tmp = 0L; move32(); for (i = 0; i < L_SUBFR; i++) L_tmp = L_mac(L_tmp, vec[i], vec[i]); alp = roundL(L_shr(L_tmp, 3)); if (sub(nbbits, 72) == 0) { ipos[16] = 0; move16(); ipos[17] = 1; move16(); } } /* other stages of 2 pulses */ for (j = pos, st = 0; j < nb_pulse; j += 2, st++) { /*--------------------------------------------------* * Calculate correlation of all possible positions * * of the next 2 pulses with previous fixed pulses. * * Each pulse can have 16 possible positions. * *--------------------------------------------------*/ cor_h_vec(h, vec, ipos[j], sign, rrixix, cor_x); cor_h_vec(h, vec, ipos[j + 1], sign, rrixix, cor_y); /*--------------------------------------------------* * Find best positions of 2 pulses. * *--------------------------------------------------*/ search_ixiy(nbpos[st], ipos[j], ipos[j + 1], &ps, &alp, &ix, &iy, dn, dn2, cor_x, cor_y, rrixiy); ind[j] = ix; move16(); ind[j + 1] = iy; move16(); test();move16();move16(); if (sign[ix] < 0) p0 = h_inv - ix; else p0 = h - ix; test();move16();move16(); if (sign[iy] < 0) p1 = h_inv - iy; else p1 = h - iy; for (i = 0; i < L_SUBFR; i++) { vec[i] = add(vec[i], add(*p0++, *p1++)); /* can saturate here. */ move16(); } } /* memorise the best codevector */ ps = mult(ps, ps); s = L_msu(L_mult(alpk, ps), psk, alp); test(); if (s > 0) { psk = ps; move16(); alpk = alp; move16(); for (i = 0; i < nb_pulse; i++) { codvec[i] = ind[i]; move16(); } for (i = 0; i < L_SUBFR; i++) { y[i] = vec[i]; move16(); } } } /*-------------------------------------------------------------------* * Build the codeword, the filtered codeword and index of codevector.* *-------------------------------------------------------------------*/ for (i = 0; i < NPMAXPT * NB_TRACK; i++) { ind[i] = -1; move16(); } for (i = 0; i < L_SUBFR; i++) { code[i] = 0; move16(); y[i] = shr_r(y[i], 3); move16(); /* Q12 to Q9 */ } val = shr(512, h_shift); /* codeword in Q9 format */ for (k = 0; k < nb_pulse; k++) { i = codvec[k]; move16(); /* read pulse position */ j = sign[i]; move16(); /* read sign */ index = shr(i, 2); /* index = pos of pulse (0..15) */ track = (Word16) (i & 0x03); logic16(); /* track = i % NB_TRACK (0..3) */ if (j > 0) { code[i] = add(code[i], val); move16(); codvec[k] = add(codvec[k], (2 * L_SUBFR)); move16(); } else { code[i] = sub(code[i], val); move16(); index = add(index, NB_POS); move16(); } i = extract_l(L_shr(L_mult(track, NPMAXPT), 1)); test();move16(); while (ind[i] >= 0) { i = add(i, 1); } ind[i] = index; move16(); } k = 0; move16(); /* Build index of codevector */ test();test();test();test();test();test();test(); if (sub(nbbits, 20) == 0) { for (track = 0; track < NB_TRACK; track++) { _index[track] = extract_l(quant_1p_N1(ind[k], 4)); k += NPMAXPT; } } else if (sub(nbbits, 36) == 0) { for (track = 0; track < NB_TRACK; track++) { _index[track] = extract_l(quant_2p_2N1(ind[k], ind[k + 1], 4)); k += NPMAXPT; } } else if (sub(nbbits, 44) == 0) { for (track = 0; track < NB_TRACK - 2; track++) { _index[track] = extract_l(quant_3p_3N1(ind[k], ind[k + 1], ind[k + 2], 4)); k += NPMAXPT; } for (track = 2; track < NB_TRACK; track++) { _index[track] = extract_l(quant_2p_2N1(ind[k], ind[k + 1], 4)); k += NPMAXPT; } } else if (sub(nbbits, 52) == 0) { for (track = 0; track < NB_TRACK; track++) { _index[track] = extract_l(quant_3p_3N1(ind[k], ind[k + 1], ind[k + 2], 4)); k += NPMAXPT; } } else if (sub(nbbits, 64) == 0) { for (track = 0; track < NB_TRACK; track++) { L_index = quant_4p_4N(&ind[k], 4); _index[track] = extract_l(L_shr(L_index, 14) & 3); _index[track + NB_TRACK] = extract_l(L_index & 0x3FFF); k += NPMAXPT; } } else if (sub(nbbits, 72) == 0) { for (track = 0; track < NB_TRACK - 2; track++) { L_index = quant_5p_5N(&ind[k], 4); _index[track] = extract_l(L_shr(L_index, 10) & 0x03FF); _index[track + NB_TRACK] = extract_l(L_index & 0x03FF); k += NPMAXPT; } for (track = 2; track < NB_TRACK; track++) { L_index = quant_4p_4N(&ind[k], 4); _index[track] = extract_l(L_shr(L_index, 14) & 3); _index[track + NB_TRACK] = extract_l(L_index & 0x3FFF); k += NPMAXPT; } } else if (sub(nbbits, 88) == 0) { for (track = 0; track < NB_TRACK; track++) { L_index = quant_6p_6N_2(&ind[k], 4); _index[track] = extract_l(L_shr(L_index, 11) & 0x07FF); _index[track + NB_TRACK] = extract_l(L_index & 0x07FF); k += NPMAXPT; } } return; } /*-------------------------------------------------------------------* * Function cor_h_vec() * * ~~~~~~~~~~~~~~~~~~~~~ * * Compute correlations of h[] with vec[] for the specified track. * *-------------------------------------------------------------------*/ static void cor_h_vec( Word16 h[], /* (i) scaled impulse response */ Word16 vec[], /* (i) scaled vector (/8) to correlate with h[] */ Word16 track, /* (i) track to use */ Word16 sign[], /* (i) sign vector */ Word16 rrixix[][NB_POS], /* (i) correlation of h[x] with h[x] */ Word16 cor[] /* (o) result of correlation (NB_POS elements) */ ) { Word16 i, j, pos, corr; Word16 *p0, *p1, *p2; Word32 L_sum; p0 = rrixix[track]; move16(); pos = track; move16(); for (i = 0; i < NB_POS; i++, pos += STEP) { L_sum = 0L; move32(); p1 = h; move16(); p2 = &vec[pos]; move16(); for (j = pos; j < L_SUBFR; j++) L_sum = L_mac(L_sum, *p1++, *p2++); L_sum = L_shl(L_sum, 1); corr = roundL(L_sum); cor[i] = add(mult(corr, sign[pos]), *p0++); move16(); } return; } /*-------------------------------------------------------------------* * Function search_ixiy() * * ~~~~~~~~~~~~~~~~~~~~~~~ * * Find the best positions of 2 pulses in a subframe. * *-------------------------------------------------------------------*/ static void search_ixiy( Word16 nb_pos_ix, /* (i) nb of pos for pulse 1 (1..8) */ Word16 track_x, /* (i) track of pulse 1 */ Word16 track_y, /* (i) track of pulse 2 */ Word16 * ps, /* (i/o) correlation of all fixed pulses */ Word16 * alp, /* (i/o) energy of all fixed pulses */ Word16 * ix, /* (o) position of pulse 1 */ Word16 * iy, /* (o) position of pulse 2 */ Word16 dn[], /* (i) corr. between target and h[] */ Word16 dn2[], /* (i) vector of selected positions */ Word16 cor_x[], /* (i) corr. of pulse 1 with fixed pulses */ Word16 cor_y[], /* (i) corr. of pulse 2 with fixed pulses */ Word16 rrixiy[][MSIZE] /* (i) corr. of pulse 1 with pulse 2 */ ) { Word16 x, y, pos, thres_ix; Word16 ps1, ps2, sq, sqk; Word16 alp_16, alpk; Word16 *p0, *p1, *p2; Word32 s, alp0, alp1, alp2; p0 = cor_x; move16(); p1 = cor_y; move16(); p2 = rrixiy[track_x]; move16(); thres_ix = sub(nb_pos_ix, NB_MAX); alp0 = L_deposit_h(*alp); alp0 = L_add(alp0, 0x00008000L); /* for rounding */ sqk = -1; move16(); alpk = 1; move16(); for (x = track_x; x < L_SUBFR; x += STEP) { ps1 = add(*ps, dn[x]); alp1 = L_mac(alp0, *p0++, 4096); test(); if (sub(dn2[x], thres_ix) < 0) { pos = -1; move16(); for (y = track_y; y < L_SUBFR; y += STEP) { ps2 = add(ps1, dn[y]); alp2 = L_mac(alp1, *p1++, 4096); alp2 = L_mac(alp2, *p2++, 8192); alp_16 = extract_h(alp2); sq = mult(ps2, ps2); s = L_msu(L_mult(alpk, sq), sqk, alp_16); test(); if (s > 0) { sqk = sq; move16(); alpk = alp_16; move16(); pos = y; move16(); } } p1 -= NB_POS; test(); if (pos >= 0) { *ix = x; move16(); *iy = pos; move16(); } } else { p2 += NB_POS; } } *ps = add(*ps, add(dn[*ix], dn[*iy])); move16(); *alp = alpk; move16(); return; }