www.pudn.com > g729.rar > acelp_ca.c
/*
ITU-T G.729A Speech Coder ANSI-C Source Code
Version 1.1 Last modified: September 1996
Copyright (c) 1996,
AT&T, France Telecom, NTT, Universite de Sherbrooke
All rights reserved.
*/
/*---------------------------------------------------------------------------*
* Function ACELP_Code_A() *
* ~~~~~~~~~~~~~~~~~~~~~~~~ *
* Find Algebraic codebook for G.729A *
*--------------------------------------------------------------------------*/
#include "typedef.h"
#include "basic_op.h"
#include "ld8a.h"
/* Constants defined in ld8a.h */
/* L_SUBFR -> Lenght of subframe. */
/* NB_POS -> Number of positions for each pulse. */
/* STEP -> Step betweem position of the same pulse. */
/* MSIZE -> Size of vectors for cross-correlation between two pulses. */
/* local routines definition */
static void Cor_h(
Word16 *H, /* (i) Q12 :Impulse response of filters */
Word16 *rr /* (o) :Correlations of H[] */
);
static Word16 D4i40_17_fast(/*(o) : Index of pulses positions. */
Word16 dn[], /* (i) : Correlations between h[] and Xn[]. */
Word16 *rr, /* (i) : Correlations of impulse response h[]. */
Word16 h[], /* (i) Q12: Impulse response of filters. */
Word16 cod[], /* (o) Q13: Selected algebraic codeword. */
Word16 y[], /* (o) Q12: Filtered algebraic codeword. */
Word16 *sign /* (o) : Signs of 4 pulses. */
);
/*-----------------------------------------------------------------*
* Main ACELP function. *
*-----------------------------------------------------------------*/
Word16 ACELP_Code_A( /* (o) :index of pulses positions */
Word16 x[], /* (i) :Target vector */
Word16 h[], /* (i) Q12 :Inpulse response of filters */
Word16 T0, /* (i) :Pitch lag */
Word16 pitch_sharp, /* (i) Q14 :Last quantized pitch gain */
Word16 code[], /* (o) Q13 :Innovative codebook */
Word16 y[], /* (o) Q12 :Filtered innovative codebook */
Word16 *sign /* (o) :Signs of 4 pulses */
)
{
Word16 i, index, sharp;
Word16 Dn[L_SUBFR];
Word16 rr[DIM_RR];
/*-----------------------------------------------------------------*
* Include fixed-gain pitch contribution into impulse resp. h[] *
* Find correlations of h[] needed for the codebook search. *
*-----------------------------------------------------------------*/
sharp = shl(pitch_sharp, 1); /* From Q14 to Q15 */
if (T0 < L_SUBFR)
for (i = T0; i < L_SUBFR; i++) /* h[i] += pitch_sharp*h[i-T0] */
h[i] = myadd(h[i], mult(h[i-T0], sharp)); //modified
Cor_h(h, rr);
/*-----------------------------------------------------------------*
* Compute correlation of target vector with impulse response. *
*-----------------------------------------------------------------*/
Cor_h_X(h, x, Dn);
/*-----------------------------------------------------------------*
* Find innovative codebook. *
*-----------------------------------------------------------------*/
index = D4i40_17_fast(Dn, rr, h, code, y, sign);
/*-----------------------------------------------------------------*
* Compute innovation vector gain. *
* Include fixed-gain pitch contribution into code[]. *
*-----------------------------------------------------------------*/
if(T0 < L_SUBFR)
for (i = T0; i < L_SUBFR; i++) { /* code[i] += pitch_sharp*code[i-T0] */
code[i] = myadd(code[i], mult(code[i-T0], sharp));
}
return index;
}
/*--------------------------------------------------------------------------*
* Function Cor_h() *
* ~~~~~~~~~~~~~~~~~ *
* Compute correlations of h[] needed for the codebook search. *
*--------------------------------------------------------------------------*/
static void Cor_h(
Word16 *H, /* (i) Q12 :Impulse response of filters */
Word16 *rr /* (o) :Correlations of H[] */
)
{
Word16 *rri0i0, *rri1i1, *rri2i2, *rri3i3, *rri4i4;
Word16 *rri0i1, *rri0i2, *rri0i3, *rri0i4;
Word16 *rri1i2, *rri1i3, *rri1i4;
Word16 *rri2i3, *rri2i4;
Word16 *p0, *p1, *p2, *p3, *p4;
Word16 *ptr_hd, *ptr_hf, *ptr_h1, *ptr_h2;
Word32 cor;
Word16 i, k, ldec, l_fin_sup, l_fin_inf;
Word16 h[L_SUBFR];
/* Scaling h[] for maximum precision */
cor = 0;
for(i=0; i 0)
{
for(i=0; i 17 bits; 4 pulses in a frame of 40 samples *
* *
*------------------------------------------------------------------------*
* The code length is 40, containing 4 nonzero pulses i0, i1, i2, i3. *
* Each pulses can have 8 possible positions (positive or negative) *
* except i3 that have 16 possible positions. *
* *
* i0 (+-1) : 0, 5, 10, 15, 20, 25, 30, 35 *
* i1 (+-1) : 1, 6, 11, 16, 21, 26, 31, 36 *
* i2 (+-1) : 2, 7, 12, 17, 22, 27, 32, 37 *
* i3 (+-1) : 3, 8, 13, 18, 23, 28, 33, 38 *
* 4, 9, 14, 19, 24, 29, 34, 39 *
*------------------------------------------------------------------------*/
static Word16 D4i40_17_fast(/*(o) : Index of pulses positions. */
Word16 dn[], /* (i) : Correlations between h[] and Xn[]. */
Word16 rr[], /* (i) : Correlations of impulse response h[]. */
Word16 h[], /* (i) Q12: Impulse response of filters. */
Word16 cod[], /* (o) Q13: Selected algebraic codeword. */
Word16 y[], /* (o) Q12: Filtered algebraic codeword. */
Word16 *sign /* (o) : Signs of 4 pulses. */
)
{
Word16 i0, i1, i2, i3, ip0, ip1, ip2, ip3;
Word16 i, j, ix, iy, track, trk, max;
Word16 prev_i0, i1_offset;
Word16 psk, ps, ps0, ps1, ps2, sq, sq2;
Word16 alpk, alp, alp_16;
Word32 s, alp0, alp1, alp2;
Word16 *p0, *p1, *p2, *p3, *p4;
Word16 sign_dn[L_SUBFR], sign_dn_inv[L_SUBFR], *psign;
Word16 tmp_vect[NB_POS];
Word16 *rri0i0, *rri1i1, *rri2i2, *rri3i3, *rri4i4;
Word16 *rri0i1, *rri0i2, *rri0i3, *rri0i4;
Word16 *rri1i2, *rri1i3, *rri1i4;
Word16 *rri2i3, *rri2i4;
Word16 *ptr_rri0i3_i4;
Word16 *ptr_rri1i3_i4;
Word16 *ptr_rri2i3_i4;
Word16 *ptr_rri3i3_i4;
/* Init pointers */
rri0i0 = rr;
rri1i1 = rri0i0 + NB_POS;
rri2i2 = rri1i1 + NB_POS;
rri3i3 = rri2i2 + NB_POS;
rri4i4 = rri3i3 + NB_POS;
rri0i1 = rri4i4 + NB_POS;
rri0i2 = rri0i1 + MSIZE;
rri0i3 = rri0i2 + MSIZE;
rri0i4 = rri0i3 + MSIZE;
rri1i2 = rri0i4 + MSIZE;
rri1i3 = rri1i2 + MSIZE;
rri1i4 = rri1i3 + MSIZE;
rri2i3 = rri1i4 + MSIZE;
rri2i4 = rri2i3 + MSIZE;
/*-----------------------------------------------------------------------*
* Chose the sign of the impulse. *
*-----------------------------------------------------------------------*/
for (i=0; i= 0)
{
sign_dn[i] = MAX_16;
sign_dn_inv[i] = MIN_16;
}
else
{
sign_dn[i] = MIN_16;
sign_dn_inv[i] = MAX_16;
dn[i] = negate(dn[i]);
}
}
/*-------------------------------------------------------------------*
* Modification of rrixiy[] to take signs into account. *
*-------------------------------------------------------------------*/
p0 = rri0i1;
p1 = rri0i2;
p2 = rri0i3;
p3 = rri0i4;
for(i0=0; i0 0) && (mysub(prev_i0,j) != 0))
{
max = dn[j];
i0 = j;
}
}
prev_i0 = i0;
j = mult(i0, 6554); /* j = i0/5 */
p0 = rri2i2 + j;
ps1 = dn[i0];
alp1 = L_mult(*p0, _1_4);
/* i1 loop: 8 positions in track 2 */
p0 = ptr_rri2i3_i4 + shl(j, 3);
p1 = ptr_rri3i3_i4;
for (i1=track; i1 0)
{
sq = sq2;
ps = ps2;
alp = alp_16;
ix = i0;
iy = i1;
}
}
}
i0 = ix;
i1 = iy;
i1_offset = shl(mult(i1, 6554), 3); /* j = 8*(i1/5) */
/*------------------------------------------------------------------*
* depth first search 3, phase B: track 0 and 1. *
*------------------------------------------------------------------*/
ps0 = ps;
alp0 = L_mult(alp, _1_4);
sq = -1;
alp = 1;
/* build vector for next loop to decrease complexity */
p0 = rri1i2 + mult(i0, 6554);
p1 = ptr_rri1i3_i4 + mult(i1, 6554);
p2 = rri1i1;
p3 = tmp_vect;
for (i3=1; i3 0)
{
sq = sq2;
alp = alp_16;
ix = i2;
iy = i3;
}
}
}
/*----------------------------------------------------------------*
* depth first search 3: compare codevector with the best case. *
*----------------------------------------------------------------*/
s = L_msu(L_mult(alpk,sq),psk,alp);
if (s > 0)
{
psk = sq;
alpk = alp;
ip2 = i0;
ip3 = i1;
ip0 = ix;
ip1 = iy;
}
/*------------------------------------------------------------------*
* depth first search 4, phase A: track 3 and 0. *
*------------------------------------------------------------------*/
sq = -1;
alp = 1;
/* i0 loop: 2 positions in track 3/4 */
prev_i0 = -1;
for (i=0; i<2; i++)
{
max = -1;
/* search "dn[]" maximum position in track 3/4 */
for (j=track; j 0) && (mysub(prev_i0,j) != 0))
{
max = dn[j];
i0 = j;
}
}
prev_i0 = i0;
j = mult(i0, 6554); /* j = i0/5 */
p0 = ptr_rri3i3_i4 + j;
ps1 = dn[i0];
alp1 = L_mult(*p0, _1_4);
/* i1 loop: 8 positions in track 0 */
p0 = ptr_rri0i3_i4 + j;
p1 = rri0i0;
for (i1=0; i1 0)
{
sq = sq2;
ps = ps2;
alp = alp_16;
ix = i0;
iy = i1;
}
}
}
i0 = ix;
i1 = iy;
i1_offset = shl(mult(i1, 6554), 3); /* j = 8*(i1/5) */
/*------------------------------------------------------------------*
* depth first search 4, phase B: track 1 and 2. *
*------------------------------------------------------------------*/
ps0 = ps;
alp0 = L_mult(alp, _1_4);
sq = -1;
alp = 1;
/* build vector for next loop to decrease complexity */
p0 = ptr_rri2i3_i4 + mult(i0, 6554);
p1 = rri0i2 + i1_offset;
p2 = rri2i2;
p3 = tmp_vect;
for (i3=2; i3 0)
{
sq = sq2;
alp = alp_16;
ix = i2;
iy = i3;
}
}
}
/*----------------------------------------------------------------*
* depth first search 1: compare codevector with the best case. *
*----------------------------------------------------------------*/
s = L_msu(L_mult(alpk,sq),psk,alp);
if (s > 0)
{
psk = sq;
alpk = alp;
ip3 = i0;
ip0 = i1;
ip1 = ix;
ip2 = iy;
}
ptr_rri0i3_i4 = rri0i4;
ptr_rri1i3_i4 = rri1i4;
ptr_rri2i3_i4 = rri2i4;
ptr_rri3i3_i4 = rri4i4;
}
/* Set the sign of impulses */
i0 = sign_dn[ip0];
i1 = sign_dn[ip1];
i2 = sign_dn[ip2];
i3 = sign_dn[ip3];
/* Find the codeword corresponding to the selected positions */
for(i=0; i 0)
for(i=ip0, j=0; i 0)
for(i=ip1, j=0; i 0)
for(i=ip2, j=0; i 0)
for(i=ip3, j=0; i 0) i = myadd(i, 1);
if(i1 > 0) i = myadd(i, 2);
if(i2 > 0) i = myadd(i, 4);
if(i3 > 0) i = myadd(i, 8);*/
if(i0 > 0) i = i+1;
if(i1 > 0) i = i+2;
if(i2 > 0) i = i+4;
if(i3 > 0) i = i+8;
*sign = i;
ip0 = mult(ip0, 6554); /* ip0/5 */
ip1 = mult(ip1, 6554); /* ip1/5 */
ip2 = mult(ip2, 6554); /* ip2/5 */
i = mult(ip3, 6554); /* ip3/5 */
j = myadd(i, shl(i, 2)); /* j = i*5 */
j = mysub(ip3, myadd(j, 3)); /* j= ip3%5 -3 */
ip3 = myadd(shl(i, 1), j);
i = myadd(ip0, shl(ip1, 3));
i = myadd(i , shl(ip2, 6));
i = myadd(i , shl(ip3, 9));
return i;
}