/*
**************************************************************************
*
* Function : Az_lsp
* Purpose : Compute the LSPs from the LP coefficients
*
**************************************************************************
*/
void Az_lsp (
Word16 a[], /* (i) : predictor coefficients (MP1) */
Word16 lsp[], /* (o) : line spectral pairs (M) */
Word16 old_lsp[] /* (i) : old lsp[] (in case not found 10 roots) (M) */
)
{
Word16 i, j, nf, ip;
Word16 xlow, ylow, xhigh, yhigh, xmid, ymid, xint;
Word16 x, y, sign, exp;
Word16 *coef;
Word16 f1[M / 2 + 1], f2[M / 2 + 1];
Word32 t0;
/*-------------------------------------------------------------*
* find the sum and diff. pol. F1(z) and F2(z) *
* F1(z) <--- F1(z)/(1+z**-1) & F2(z) <--- F2(z)/(1-z**-1) *
* *
* f1[0] = 1.0; *
* f2[0] = 1.0; *
* *
* for (i = 0; i< NC; i++) *
* { *
* f1[i+1] = a[i+1] + a[M-i] - f1[i] ; *
* f2[i+1] = a[i+1] - a[M-i] + f2[i] ; *
* } *
*-------------------------------------------------------------*/
f1[0] = 1024; move16 (); /* f1[0] = 1.0 */
f2[0] = 1024; move16 (); /* f2[0] = 1.0 */
for (i = 0; i < NC; i++)
{
t0 = L_mult (a[i + 1], 8192); /* x = (a[i+1] + a[M-i]) >> 2 */
t0 = L_mac (t0, a[M - i], 8192);
x = extract_h (t0);
/* f1[i+1] = a[i+1] + a[M-i] - f1[i] */
f1[i + 1] = sub (x, f1[i]);move16 ();
t0 = L_mult (a[i + 1], 8192); /* x = (a[i+1] - a[M-i]) >> 2 */
t0 = L_msu (t0, a[M - i], 8192);
x = extract_h (t0);
/* f2[i+1] = a[i+1] - a[M-i] + f2[i] */
f2[i + 1] = add (x, f2[i]);move16 ();
}
/*-------------------------------------------------------------*
* find the LSPs using the Chebychev pol. evaluation *
*-------------------------------------------------------------*/
nf = 0; move16 (); /* number of found frequencies */
ip = 0; move16 (); /* indicator for f1 or f2 */
coef = f1; move16 ();
xlow = grid[0]; move16 ();
ylow = Chebps (xlow, coef, NC);move16 ();
j = 0;
test (); test ();
/* while ( (nf < M) && (j < grid_points) ) */
while ((sub (nf, M) < 0) && (sub (j, grid_points) < 0))
{
j++;
xhigh = xlow; move16 ();
yhigh = ylow; move16 ();
xlow = grid[j]; move16 ();
ylow = Chebps (xlow, coef, NC);
move16 ();
test ();
if (L_mult (ylow, yhigh) <= (Word32) 0L)
{
/* divide 4 times the interval */
for (i = 0; i < 4; i++)
{
/* xmid = (xlow + xhigh)/2 */
xmid = add (shr (xlow, 1), shr (xhigh, 1));
ymid = Chebps (xmid, coef, NC);
move16 ();
test ();
if (L_mult (ylow, ymid) <= (Word32) 0L)
{
yhigh = ymid; move16 ();
xhigh = xmid; move16 ();
}
else
{
ylow = ymid; move16 ();
xlow = xmid; move16 ();
}
}
/*-------------------------------------------------------------*
* Linear interpolation *
* xint = xlow - ylow*(xhigh-xlow)/(yhigh-ylow); *
*-------------------------------------------------------------*/
x = sub (xhigh, xlow);
y = sub (yhigh, ylow);
test ();
if (y == 0)
{
xint = xlow; move16 ();
}
else
{
sign = y; move16 ();
y = abs_s (y);
exp = norm_s (y);
y = shl (y, exp);
y = div_s ((Word16) 16383, y);
t0 = L_mult (x, y);
t0 = L_shr (t0, sub (20, exp));
y = extract_l (t0); /* y= (xhigh-xlow)/(yhigh-ylow) */
test ();
if (sign < 0)
y = negate (y);
t0 = L_mult (ylow, y);
t0 = L_shr (t0, 11);
xint = sub (xlow, extract_l (t0)); /* xint = xlow - ylow*y */
}
lsp[nf] = xint; move16 ();
xlow = xint; move16 ();
nf++;
test ();
if (ip == 0)
{
ip = 1; move16 ();
coef = f2; move16 ();
}
else
{
ip = 0; move16 ();
coef = f1; move16 ();
}
ylow = Chebps (xlow, coef, NC);
move16 ();
}
test (); test ();
}
/* Check if M roots found */
test ();
if (sub (nf, M) < 0)
{
for (i = 0; i < M; i++)
{
lsp[i] = old_lsp[i]; move16 ();
}
}
return;
}
void Az_lsp (
INT16 a[], /* (i) : predictor coefficients */
INT16 lsp[], /* (o) : line spectral pairs */
INT16 old_lsp[] /* (i) : old lsp[] (in case not found 10 roots) */
)
{
INT16 i, j, nf, ip;
INT16 xlow, ylow, xhigh, yhigh, xmid, ymid, xint;
INT16 x, y, sign, exp;
INT16 *coef;
INT16 f1[M / 2 + 1], f2[M / 2 + 1];
INT32 t0=0;
VPP_EFR_PROFILE_FUNCTION_ENTER(Az_lsp);
/*-------------------------------------------------------------*
* find the sum and diff. pol. F1(z) and F2(z) *
* F1(z) <--- F1(z)/(1+z**-1) & F2(z) <--- F2(z)/(1-z**-1) *
* *
* f1[0] = 1.0; *
* f2[0] = 1.0; *
* *
* for (i = 0; i< NC; i++) *
* { *
* f1[i+1] = a[i+1] + a[M-i] - f1[i] ; *
* f2[i+1] = a[i+1] - a[M-i] + f2[i] ; *
* } *
*-------------------------------------------------------------*/
f1[0] = 1024; /* f1[0] = 1.0 */
f2[0] = 1024; /* f2[0] = 1.0 */
for (i = 0; i < NC; i++)
{
//VPP_MLX16 (t0_hi,t0_lo,a[i + 1], 8192);
//VPP_MLA16 ( t0_hi, t0_lo, a[M - i], 8192);
//t0 = VPP_SCALE64_TO_16( t0_hi, t0_lo);
//x = EXTRACT_H(t0);
t0 = (INT32) a[i + 1] + (INT32)a[M - i];
x = (INT16)(L_SHR_D(t0,2));
/* f1[i+1] = a[i+1] + a[M-i] - f1[i] */
f1[i + 1] = SUB (x, f1[i]);
//VPP_MLX16(t0_hi, t0_lo, a[i + 1], 8192);
//VPP_MLA16(t0_hi, t0_lo, a[M - i], -8192);
//x = EXTRACT_H(VPP_SCALE64_TO_16(t0_hi, t0_lo));
t0 = (INT32) a[i + 1] - (INT32)a[M - i];
x = (INT16)(L_SHR_D(t0,2));
//f2[i + 1] = add (x, f2[i]);
f2[i + 1] = ADD(x, f2[i]);
}
/*-------------------------------------------------------------*
* find the LSPs using the Chebychev pol. evaluation *
*-------------------------------------------------------------*/
nf = 0; /* number of found frequencies */
ip = 0; /* indicator for f1 or f2 */
coef = f1;
xlow = grid[0];
ylow = Chebps (xlow, coef, NC);
j = 0;
/* while ( (nf < M) && (j < grid_points) ) */
//while ((sub (nf, M) < 0) && (sub (j, grid_points) < 0))
while ((SUB (nf, M) < 0) && (SUB (j, grid_points) < 0))
{
j++;
xhigh = xlow;
yhigh = ylow;
xlow = grid[j];
ylow = Chebps (xlow, coef, NC);
//if (L_mult (ylow, yhigh) <= (INT32) 0L)
if (L_MULT(ylow, yhigh) <= (INT32) 0L)
{
/* divide 4 times the interval */
for (i = 0; i < 4; i++)
{
/* xmid = (xlow + xhigh)/2 */
// xmid = add (shr (xlow, 1), shr (xhigh, 1));
xmid = ADD ((SHR_D(xlow, 1)),(SHR_D(xhigh, 1)));
ymid = Chebps (xmid, coef, NC);
//if (L_mult (ylow, ymid) <= (INT32) 0L)
if (L_MULT(ylow, ymid) <= (INT32) 0L)
{
yhigh = ymid;
xhigh = xmid;
}
else
{
ylow = ymid;
xlow = xmid;
}
}
/*-------------------------------------------------------------*
* Linear interpolation *
* xint = xlow - ylow*(xhigh-xlow)/(yhigh-ylow); *
*-------------------------------------------------------------*/
//x = sub (xhigh, xlow);
x = SUB (xhigh, xlow);
//y = sub (yhigh, ylow);
y = SUB (yhigh, ylow);
if (y == 0)
{
xint = xlow;
}
else
{
sign = y;
//y = abs_s (y);
y = ABS_S(y);
exp = norm_s (y);
//y = shl (y, exp);
y = SHL(y, exp);
y = div_s ((INT16) 16383, y);
//t0 = L_mult (x, y);
t0 = L_MULT(x, y);
//t0 = L_shr (t0, sub (20, exp));
t0 = L_SHR_V(t0, SUB (20, exp));
//y = extract_l (t0); /* y= (xhigh-xlow)/(yhigh-ylow) */
y = EXTRACT_L(t0);
if (sign < 0)
{
//y = negate (y);
y = NEGATE(y);
}
//t0 = L_mult (ylow, y);
t0 = L_MULT(ylow, y);
//t0 = L_shr (t0, 11);
t0 = L_SHR_D(t0, 11);
//xint = sub (xlow, extract_l (t0)); /* xint = xlow - ylow*y */
xint = SUB (xlow, EXTRACT_L(t0));
}
lsp[nf] = xint;
xlow = xint;
nf++;
if (ip == 0)
{
ip = 1;
coef = f2;
}
else
{
ip = 0;
coef = f1;
}
ylow = Chebps (xlow, coef, NC);
}
}
/* Check if M roots found */
//if (sub (nf, M) < 0)
if (SUB (nf, M) < 0)
{
for (i = 0; i < M; i++)
{
lsp[i] = old_lsp[i];
}
}
VPP_EFR_PROFILE_FUNCTION_EXIT(Az_lsp);
return;
}
