www.pudn.com > 200411301125332697.rar > acelp_co.c
/*
ITU-T G.729 Speech Coder ANSI-C Source Code
Version 3.3 Last modified: December 26, 1995
Copyright (c) 1996,
AT&T, France Telecom, NTT, Universite de Sherbrooke, Lucent Technologies
All rights reserved.
*/
/*---------------------------------------------------------------------------*
* Function ACELP_CODEBOOK() *
* ~~~~~~~~~~~~~~~~~~~~~~~~~~ *
* Find Algebraic codebook. *
*--------------------------------------------------------------------------*/
#include "typedef.h"
#include "basic_op.h"
#include "ld8k.h"
static void Cor_h(
Word16 *H, /* (i) Q12 :Impulse response of filters */
Word16 *rr /* (o) :Correlations of H[] */
);
static void Cor_h_X(
Word16 h[], /* (i) Q12 :Impulse response of filters */
Word16 X[], /* (i) Q12 :Target vector */
Word16 D[] /* (o) :Correlations between h[] and D[] */
/* Normalized to 13 bits */
);
static Word16 D4i40_17( /* (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 i_subfr /* (i) : subframe flag */
);
Word16 ACELP_Codebook( /* (o) :index of pulses positions */
Word16 x[], /* (i) :Target vector */
Word16 h[], /* (i) Q12 :Impulse response of filters */
Word16 T0, /* (i) :Pitch lag */
Word16 pitch_sharp, /* (i) Q14 :Last quantized pitch gain */
Word16 i_subfr, /* (i) :Indicator of 1st subframe, */
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 (sub(T0, L_SUBFR)<0)
for (i = T0; i < L_SUBFR; i++){ /* h[i] += pitch_sharp*h[i-T0] */
h[i] = add(h[i], mult(h[i-T0], sharp));
}
Cor_h(h, rr);
/*-----------------------------------------------------------------*
* Compute correlation of target vector with impulse response. *
*-----------------------------------------------------------------*/
Cor_h_X(h, x, Dn);
/*-----------------------------------------------------------------*
* Find innovative codebook. *
*-----------------------------------------------------------------*/
index = D4i40_17(Dn, rr, h, code, y, sign, i_subfr);
/*-----------------------------------------------------------------*
* Compute innovation vector gain. *
* Include fixed-gain pitch contribution into code[]. *
*-----------------------------------------------------------------*/
if(sub(T0 ,L_SUBFR) <0)
for (i = T0; i < L_SUBFR; i++) { /* code[i] += pitch_sharp*code[i-T0] */
code[i] = add(code[i], mult(code[i-T0], sharp));
}
return index;
}
/*--------------------------------------------------------------------------*
* Function Corr_h_X() *
* ~~~~~~~~~~~~~~~~~~~~ *
* Compute correlations of input response h[] with the target vector X[]. *
*--------------------------------------------------------------------------*/
static void Cor_h_X(
Word16 h[], /* (i) Q12 :Impulse response of filters */
Word16 X[], /* (i) :Target vector */
Word16 D[] /* (o) :Correlations between h[] and D[] */
/* Normalized to 13 bits */
)
{
Word16 i, j;
Word32 s, max, L_temp;
Word32 y32[L_SUBFR];
/* first keep the result on 32 bits and find absolute maximum */
max = 0;
for (i = 0; i < L_SUBFR; i++)
{
s = 0;
for (j = i; j < L_SUBFR; j++)
s = L_mac(s, X[j], h[j-i]);
y32[i] = s;
s = L_abs(s);
L_temp =L_sub(s,max);
if(L_temp>0L) {
max = s;
}
}
/* Find the number of right shifts to do on y32[] */
/* so that maximum is on 13 bits */
j = norm_l(max);
if( sub(j,16) > 0) {
j = 16;
}
j = sub(18, j);
for(i=0; i0L )
{
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 extra;
static Word16 D4i40_17( /* (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 i_subfr /* (i) : subframe flag */
)
{
Word16 i0, i1, i2, i3, ip0, ip1, ip2, ip3;
Word16 i, j, time;
Word16 ps0, ps1, ps2, ps3, alp, alp0;
Word32 alp1, alp2, alp3, L32;
Word16 ps3c, psc, alpha;
Word16 average, max0, max1, max2, thres;
Word32 L_temp;
Word16 *rri0i0, *rri1i1, *rri2i2, *rri3i3, *rri4i4;
Word16 *rri0i1, *rri0i2, *rri0i3, *rri0i4;
Word16 *rri1i2, *rri1i3, *rri1i4;
Word16 *rri2i3, *rri2i4;
Word16 *ptr_ri0i0, *ptr_ri1i1, *ptr_ri2i2, *ptr_ri3i3, *ptr_ri4i4;
Word16 *ptr_ri0i1, *ptr_ri0i2, *ptr_ri0i3, *ptr_ri0i4;
Word16 *ptr_ri1i2, *ptr_ri1i3, *ptr_ri1i4;
Word16 *ptr_ri2i3, *ptr_ri2i4;
Word16 p_sign[L_SUBFR];
/* 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;
/*-----------------------------------------------------------------------*
* Reset max_time for 1st subframe. *
*-----------------------------------------------------------------------*/
if (i_subfr == 0){ extra = 30; }
/*-----------------------------------------------------------------------*
* Chose the sign of the impulse. *
*-----------------------------------------------------------------------*/
for (i=0; i= 0)
{
p_sign[i] = 0x7fff;
}
else
{
p_sign[i] = (Word16)0x8000;
Dn[i] = negate(Dn[i]);
}
}
/*-------------------------------------------------------------------*
* - Compute the search threshold after three pulses *
*-------------------------------------------------------------------*/
/* Find maximum of Dn[i0]+Dn[i1]+Dn[i2] */
max0 = Dn[0];
max1 = Dn[1];
max2 = Dn[2];
for (i = 5; i < L_SUBFR; i+=STEP)
{
if (sub(Dn[i] , max0) > 0){ max0 = Dn[i]; }
if (sub(Dn[i+1], max1) > 0){ max1 = Dn[i+1]; }
if (sub(Dn[i+2], max2) > 0){ max2 = Dn[i+2]; }
}
max0 = add(max0, max1);
max0 = add(max0, max2);
/* Find average of Dn[i0]+Dn[i1]+Dn[i2] */
L32 = 0;
for (i = 0; i < L_SUBFR; i+=STEP)
{
L32 = L_mac(L32, Dn[i], 1);
L32 = L_mac(L32, Dn[i+1], 1);
L32 = L_mac(L32, Dn[i+2], 1);
}
average =extract_l( L_shr(L32, 4)); /* 1/8 of sum */
/* thres = average + (max0-average)*THRESHFCB; */
thres = sub(max0, average);
thres = mult(thres, THRESHFCB);
thres = add(thres, average);
/*-------------------------------------------------------------------*
* Modification of rrixiy[] to take signs into account. *
*-------------------------------------------------------------------*/
ptr_ri0i1 = rri0i1;
ptr_ri0i2 = rri0i2;
ptr_ri0i3 = rri0i3;
ptr_ri0i4 = rri0i4;
for(i0=0; i0 0)
{
ptr_ri3i3 = rri3i3; /* Init. pointers that depend on 4th loop */
for (i3 = 3; i3 < L_SUBFR; i3 += STEP) /* 4th pulse loop */
{
ps3 = add(ps2, Dn[i3]);
/* alp3 = alp2 + *ptr_ri3i3++ */
/* + 2.0*( *ptr_ri0i3++ + *ptr_ri1i3++ + *ptr_ri2i3++); */
alp3 = L_mac(alp2, *ptr_ri3i3++, 1);
alp3 = L_mac(alp3, *ptr_ri0i3++, 2);
alp3 = L_mac(alp3, *ptr_ri1i3++, 2);
alp3 = L_mac(alp3, *ptr_ri2i3++, 2);
alp = extract_l(L_shr(alp3, 5));
ps3c = mult(ps3, ps3);
L_temp = L_mult(ps3c, alpha);
L_temp = L_msu(L_temp, psc, alp);
if( L_temp > 0L )
{
psc = ps3c;
alpha = alp;
ip0 = i0;
ip1 = i1;
ip2 = i2;
ip3 = i3;
}
} /* end of for i3 = */
ptr_ri0i3 -= NB_POS;
ptr_ri1i3 -= NB_POS;
ptr_ri4i4 = rri4i4; /* Init. pointers that depend on 4th loop */
for (i3 = 4; i3 < L_SUBFR; i3 += STEP) /* 4th pulse loop */
{
ps3 = add(ps2, Dn[i3]);
/* alp3 = alp2 + *ptr_ri4i4++ */
/* + 2.0*( *ptr_ri0i4++ + *ptr_ri1i4++ + *ptr_ri2i4++); */
alp3 = L_mac(alp2, *ptr_ri4i4++, 1);
alp3 = L_mac(alp3, *ptr_ri0i4++, 2);
alp3 = L_mac(alp3, *ptr_ri1i4++, 2);
alp3 = L_mac(alp3, *ptr_ri2i4++, 2);
alp = extract_l(L_shr(alp3, 5));
ps3c = mult(ps3, ps3);
L_temp = L_mult(ps3c, alpha);
L_temp = L_msu(L_temp, psc, alp);
if( L_temp > 0L )
{
psc = ps3c;
alpha = alp;
ip0 = i0;
ip1 = i1;
ip2 = i2;
ip3 = i3;
}
} /* end of for i3 = */
ptr_ri0i4 -= NB_POS;
ptr_ri1i4 -= NB_POS;
time = sub(time, 1);
if(time <= 0 ) goto end_search; /* Maximum time finish */
} /* end of if >thres */
else
{
ptr_ri2i3 += NB_POS;
ptr_ri2i4 += NB_POS;
}
} /* end of for i2 = */
ptr_ri0i2 -= NB_POS;
ptr_ri1i3 += NB_POS;
ptr_ri1i4 += NB_POS;
} /* end of for i1 = */
ptr_ri0i2 += NB_POS;
ptr_ri0i3 += NB_POS;
ptr_ri0i4 += NB_POS;
} /* end of for i0 = */
end_search:
extra = time;
/* Set the sign of impulses */
i0 = p_sign[ip0];
i1 = p_sign[ip1];
i2 = p_sign[ip2];
i3 = p_sign[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 = add(i, 1);
if(i1 > 0) i = add(i, 2);
if(i2 > 0) i = add(i, 4);
if(i3 > 0) i = add(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 = add(i, shl(i, 2)); /* j = i*5 */
j = sub(ip3, add(j, 3)); /* j= ip3%5 -3 */
ip3 = add(shl(i, 1), j);
i = add(ip0, shl(ip1, 3));
i = add(i , shl(ip2, 6));
i = add(i , shl(ip3, 9));
return i;
}