void pre_big(
enum Mode mode, /* i : coder mode */
const Word16 gamma1[], /* i : spectral exp. factor 1 */
const Word16 gamma1_12k2[],/* i : spectral exp. factor 1 for EFR */
const Word16 gamma2[], /* i : spectral exp. factor 2 */
Word16 A_t[], /* i : A(z) unquantized, for 4 subframes, Q12 */
Word16 frameOffset, /* i : Start position in speech vector, Q0 */
Word16 speech[], /* i : speech, Q0 */
Word16 mem_w[], /* i/o: synthesis filter memory state, Q0 */
Word16 wsp[], /* o : weighted speech Q0 */
Flag *pOverflow /* o : overflow indicator */
)
{
Word16 Ap1[MP1]; /* A(z) with spectral expansion */
Word16 Ap2[MP1]; /* A(z) with spectral expansion */
const Word16 *g1; /* Pointer to correct gammma1 vector */
Word16 aOffset;
Word16 i;
if (mode <= MR795)
{
g1 = gamma1;
}
else
{
g1 = gamma1_12k2;
}
if (frameOffset > 0)
{
aOffset = 2 * MP1;
}
else
{
aOffset = 0;
}
/* process two subframes (which form the "big" subframe) */
for (i = 0; i < 2; i++)
{
Weight_Ai(&A_t[aOffset], g1, Ap1);
Weight_Ai(&A_t[aOffset], gamma2, Ap2);
Residu(Ap1, &speech[frameOffset], &wsp[frameOffset], L_SUBFR);
Syn_filt(Ap2, &wsp[frameOffset], &wsp[frameOffset], L_SUBFR, mem_w, 1);
aOffset = add(aOffset, MP1, pOverflow);
frameOffset = add(frameOffset, L_SUBFR, pOverflow);
}
return;
}
/*
**************************************************************************
* Function: Post_Filter
* Purpose: postfiltering of synthesis speech.
* Description:
* The postfiltering process is described as follows:
*
* - inverse filtering of syn[] through A(z/0.7) to get res2[]
* - tilt compensation filtering; 1 - MU*k*z^-1
* - synthesis filtering through 1/A(z/0.75)
* - adaptive gain control
*
**************************************************************************
*/
int Post_Filter (
Post_FilterState *st, /* i/o : post filter states */
enum Mode mode, /* i : AMR mode */
Word16 *syn, /* i/o : synthesis speech (postfiltered is output) */
Word16 *Az_4 /* i : interpolated LPC parameters in all subfr. */
)
{
/*-------------------------------------------------------------------*
* Declaration of parameters *
*-------------------------------------------------------------------*/
Word16 Ap3[MP1], Ap4[MP1]; /* bandwidth expanded LP parameters */
Word16 *Az; /* pointer to Az_4: */
/* LPC parameters in each subframe */
Word16 i_subfr; /* index for beginning of subframe */
Word16 h[L_H];
Word16 i;
Word16 temp1, temp2;
Word32 L_tmp;
Word16 *syn_work = &st->synth_buf[M];
move16 ();
/*-----------------------------------------------------*
* Post filtering *
*-----------------------------------------------------*/
Copy (syn, syn_work , L_FRAME);
Az = Az_4;
for (i_subfr = 0; i_subfr < L_FRAME; i_subfr += L_SUBFR)
{
/* Find weighted filter coefficients Ap3[] and ap[4] */
test ();
test ();
if (sub(mode, MR122) == 0 || sub(mode, MR102) == 0)
{
Weight_Ai (Az, gamma3_MR122, Ap3);
Weight_Ai (Az, gamma4_MR122, Ap4);
}
else
{
Weight_Ai (Az, gamma3, Ap3);
Weight_Ai (Az, gamma4, Ap4);
}
/* filtering of synthesis speech by A(z/0.7) to find res2[] */
Residu (Ap3, &syn_work[i_subfr], st->res2, L_SUBFR);
/* tilt compensation filter */
/* impulse response of A(z/0.7)/A(z/0.75) */
Copy (Ap3, h, M + 1);
Set_zero (&h[M + 1], L_H - M - 1);
Syn_filt (Ap4, h, h, L_H, &h[M + 1], 0);
/* 1st correlation of h[] */
L_tmp = L_mult (h[0], h[0]);
for (i = 1; i < L_H; i++)
{
L_tmp = L_mac (L_tmp, h[i], h[i]);
}
temp1 = extract_h (L_tmp);
L_tmp = L_mult (h[0], h[1]);
for (i = 1; i < L_H - 1; i++)
{
L_tmp = L_mac (L_tmp, h[i], h[i + 1]);
}
temp2 = extract_h (L_tmp);
test ();
if (temp2 <= 0)
{
temp2 = 0;
move16 ();
}
else
{
temp2 = mult (temp2, MU);
temp2 = div_s (temp2, temp1);
}
preemphasis (st->preemph_state, st->res2, temp2, L_SUBFR);
/* filtering through 1/A(z/0.75) */
Syn_filt (Ap4, st->res2, &syn[i_subfr], L_SUBFR, st->mem_syn_pst, 1);
/* scale output to input */
agc (st->agc_state, &syn_work[i_subfr], &syn[i_subfr],
AGC_FAC, L_SUBFR);
Az += MP1;
}
/* update syn_work[] buffer */
Copy (&syn_work[L_FRAME - M], &syn_work[-M], M);
return 0;
}
/*
********************************************************************************
* PUBLIC PROGRAM CODE
********************************************************************************
*/
int subframePreProc(
enum Mode mode, /* i : coder mode */
const Word16 gamma1[], /* i : spectral exp. factor 1 */
const Word16 gamma1_12k2[],/* i : spectral exp. factor 1 for EFR */
const Word16 gamma2[], /* i : spectral exp. factor 2 */
Word16 *A, /* i : A(z) unquantized for the 4 subframes */
Word16 *Aq, /* i : A(z) quantized for the 4 subframes */
Word16 *speech, /* i : speech segment */
Word16 *mem_err, /* i : pointer to error signal */
Word16 *mem_w0, /* i : memory of weighting filter */
Word16 *zero, /* i : pointer to zero vector */
Word16 ai_zero[], /* o : history of weighted synth. filter */
Word16 exc[], /* o : long term prediction residual */
Word16 h1[], /* o : impulse response */
Word16 xn[], /* o : target vector for pitch search */
Word16 res2[], /* o : long term prediction residual */
Word16 error[] /* o : error of LPC synthesis filter */
)
{
Word16 i;
Word16 Ap1[MP1]; /* A(z) with spectral expansion */
Word16 Ap2[MP1]; /* A(z) with spectral expansion */
const Word16 *g1; /* Pointer to correct gammma1 vector */
/*---------------------------------------------------------------*
* mode specific pointer to gamma1 values *
*---------------------------------------------------------------*/
test (); test ();
if ( sub(mode, MR122) == 0 || sub(mode, MR102) == 0 )
{
g1 = gamma1_12k2; move16 ();
}
else
{
g1 = gamma1; move16 ();
}
/*---------------------------------------------------------------*
* Find the weighted LPC coefficients for the weighting filter. *
*---------------------------------------------------------------*/
Weight_Ai(A, g1, Ap1);
Weight_Ai(A, gamma2, Ap2);
/*---------------------------------------------------------------*
* Compute impulse response, h1[], of weighted synthesis filter *
*---------------------------------------------------------------*/
for (i = 0; i <= M; i++)
{
ai_zero[i] = Ap1[i]; move16 ();
}
Syn_filt(Aq, ai_zero, h1, L_SUBFR, zero, 0);
Syn_filt(Ap2, h1, h1, L_SUBFR, zero, 0);
/*------------------------------------------------------------------------*
* *
* Find the target vector for pitch search: *
* *
*------------------------------------------------------------------------*/
/* LPC residual */
Residu(Aq, speech, res2, L_SUBFR);
Copy(res2, exc, L_SUBFR);
Syn_filt(Aq, exc, error, L_SUBFR, mem_err, 0);
Residu(Ap1, error, xn, L_SUBFR);
/* target signal xn[]*/
Syn_filt(Ap2, xn, xn, L_SUBFR, mem_w0, 0);
return 0;
}
void Post_Filter (
INT16 *syn, /* in/out: synthesis speech (postfiltered is output) */
INT16 *Az_4 /* input: interpolated LPC parameters in all subframes */
)
{
/*-------------------------------------------------------------------*
* Declaration of parameters *
*-------------------------------------------------------------------*/
INT16 syn_pst[L_FRAME]; /* post filtered synthesis speech */
INT16 Ap3[MP1], Ap4[MP1]; /* bandwidth expanded LP parameters */
INT16 *Az; /* pointer to Az_4: */
/* LPC parameters in each subframe */
INT16 i_subfr; /* index for beginning of subframe */
INT16 h[L_H];
INT16 i;
INT16 temp1, temp2;
//INT32 L_tmp;
register INT32 tmp_hi=0;
register UINT32 tmp_lo=0;
VPP_EFR_PROFILE_FUNCTION_ENTER(Post_Filter);
/*-----------------------------------------------------*
* Post filtering *
*-----------------------------------------------------*/
Az = Az_4;
for (i_subfr = 0; i_subfr < L_FRAME; i_subfr += L_SUBFR)
{
/* Find weighted filter coefficients Ap3[] and ap[4] */
Weight_Ai (Az, F_gamma3, Ap3);
Weight_Ai (Az, F_gamma4, Ap4);
/* filtering of synthesis speech by A(z/0.7) to find res2[] */
Residu (Ap3, &syn[i_subfr], res2, L_SUBFR);
/* tilt compensation filter */
/* impulse response of A(z/0.7)/A(z/0.75) */
Copy (Ap3, h, M + 1);
//Set_zero (&h[M + 1], L_H - M - 1);
memset ((INT8*)&h[M + 1], 0, (L_H - M - 1)<<1);
Syn_filt (Ap4, h, h, L_H, &h[M + 1], 0);
/* 1st correlation of h[] */
//L_tmp = L_MULT(h[0], h[0]);
VPP_MLX16(tmp_hi,tmp_lo, h[0], h[0]);
for (i = 1; i < L_H; i++)
{
//L_tmp = L_MAC(L_tmp, h[i], h[i]);
VPP_MLA16(tmp_hi,tmp_lo, h[i], h[i]);
}
//temp1 = extract_h (L_tmp);
//temp1 = EXTRACT_H(VPP_SCALE64_TO_16(tmp_hi,tmp_lo));
temp1 = L_SHR_D((INT32)tmp_lo, 15);
//L_tmp = L_MULT(h[0], h[1]);
VPP_MLX16(tmp_hi,tmp_lo, h[0], h[1]);
for (i = 1; i < L_H - 1; i++)
{
//L_tmp = L_MAC(L_tmp, h[i], h[i + 1]);
VPP_MLA16(tmp_hi,tmp_lo, h[i], h[i + 1]);
}
//temp2 = extract_h (L_tmp);
//temp2 = EXTRACT_H(VPP_SCALE64_TO_16(tmp_hi,tmp_lo));
temp2 = L_SHR_D((INT32)tmp_lo, 15);
if (temp2 <= 0)
{
temp2 = 0;
}
else
{
//temp2 = mult (temp2, MU);
temp2 = MULT(temp2, MU);
temp2 = div_s (temp2, temp1);
}
preemphasis (res2, temp2, L_SUBFR);
/* filtering through 1/A(z/0.75) */
Syn_filt (Ap4, res2, &syn_pst[i_subfr], L_SUBFR, mem_syn_pst, 1);
/* scale output to input */
agc (&syn[i_subfr], &syn_pst[i_subfr], AGC_FAC, L_SUBFR);
Az += MP1;
}
/* update syn[] buffer */
Copy (&syn[L_FRAME - M], &syn[-M], M);
/* overwrite synthesis speech by postfiltered synthesis speech */
Copy (syn_pst, syn, L_FRAME);
VPP_EFR_PROFILE_FUNCTION_EXIT(Post_Filter);
return;
}
