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diff --git a/src/opus-1.0.2/silk/NLSF2A.c b/src/opus-1.0.2/silk/NLSF2A.c
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--- a/src/opus-1.0.2/silk/NLSF2A.c
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-/***********************************************************************
-Copyright (c) 2006-2011, Skype Limited. All rights reserved.
-Redistribution and use in source and binary forms, with or without
-modification, are permitted provided that the following conditions
-are met:
-- Redistributions of source code must retain the above copyright notice,
-this list of conditions and the following disclaimer.
-- Redistributions in binary form must reproduce the above copyright
-notice, this list of conditions and the following disclaimer in the
-documentation and/or other materials provided with the distribution.
-- Neither the name of Internet Society, IETF or IETF Trust, nor the
-names of specific contributors, may be used to endorse or promote
-products derived from this software without specific prior written
-permission.
-THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS “AS IS”
-AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
-IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
-ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
-LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
-CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
-SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
-INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
-CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
-ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
-POSSIBILITY OF SUCH DAMAGE.
-***********************************************************************/
-
-#ifdef HAVE_CONFIG_H
-#include "config.h"
-#endif
-
-/* conversion between prediction filter coefficients and LSFs */
-/* order should be even */
-/* a piecewise linear approximation maps LSF <-> cos(LSF) */
-/* therefore the result is not accurate LSFs, but the two */
-/* functions are accurate inverses of each other */
-
-#include "SigProc_FIX.h"
-#include "tables.h"
-
-#define QA 16
-
-/* helper function for NLSF2A(..) */
-static inline void silk_NLSF2A_find_poly(
- opus_int32 *out, /* O intermediate polynomial, QA [dd+1] */
- const opus_int32 *cLSF, /* I vector of interleaved 2*cos(LSFs), QA [d] */
- opus_int dd /* I polynomial order (= 1/2 * filter order) */
-)
-{
- opus_int k, n;
- opus_int32 ftmp;
-
- out[0] = silk_LSHIFT( 1, QA );
- out[1] = -cLSF[0];
- for( k = 1; k < dd; k++ ) {
- ftmp = cLSF[2*k]; /* QA*/
- out[k+1] = silk_LSHIFT( out[k-1], 1 ) - (opus_int32)silk_RSHIFT_ROUND64( silk_SMULL( ftmp, out[k] ), QA );
- for( n = k; n > 1; n-- ) {
- out[n] += out[n-2] - (opus_int32)silk_RSHIFT_ROUND64( silk_SMULL( ftmp, out[n-1] ), QA );
- }
- out[1] -= ftmp;
- }
-}
-
-/* compute whitening filter coefficients from normalized line spectral frequencies */
-void silk_NLSF2A(
- opus_int16 *a_Q12, /* O monic whitening filter coefficients in Q12, [ d ] */
- const opus_int16 *NLSF, /* I normalized line spectral frequencies in Q15, [ d ] */
- const opus_int d /* I filter order (should be even) */
-)
-{
- /* This ordering was found to maximize quality. It improves numerical accuracy of
- silk_NLSF2A_find_poly() compared to "standard" ordering. */
- static const unsigned char ordering16[16] = {
- 0, 15, 8, 7, 4, 11, 12, 3, 2, 13, 10, 5, 6, 9, 14, 1
- };
- static const unsigned char ordering10[10] = {
- 0, 9, 6, 3, 4, 5, 8, 1, 2, 7
- };
- const unsigned char *ordering;
- opus_int k, i, dd;
- opus_int32 cos_LSF_QA[ SILK_MAX_ORDER_LPC ];
- opus_int32 P[ SILK_MAX_ORDER_LPC / 2 + 1 ], Q[ SILK_MAX_ORDER_LPC / 2 + 1 ];
- opus_int32 Ptmp, Qtmp, f_int, f_frac, cos_val, delta;
- opus_int32 a32_QA1[ SILK_MAX_ORDER_LPC ];
- opus_int32 maxabs, absval, idx=0, sc_Q16;
-
- silk_assert( LSF_COS_TAB_SZ_FIX == 128 );
- silk_assert( d==10||d==16 );
-
- /* convert LSFs to 2*cos(LSF), using piecewise linear curve from table */
- ordering = d == 16 ? ordering16 : ordering10;
- for( k = 0; k < d; k++ ) {
- silk_assert(NLSF[k] >= 0 );
-
- /* f_int on a scale 0-127 (rounded down) */
- f_int = silk_RSHIFT( NLSF[k], 15 - 7 );
-
- /* f_frac, range: 0..255 */
- f_frac = NLSF[k] - silk_LSHIFT( f_int, 15 - 7 );
-
- silk_assert(f_int >= 0);
- silk_assert(f_int < LSF_COS_TAB_SZ_FIX );
-
- /* Read start and end value from table */
- cos_val = silk_LSFCosTab_FIX_Q12[ f_int ]; /* Q12 */
- delta = silk_LSFCosTab_FIX_Q12[ f_int + 1 ] - cos_val; /* Q12, with a range of 0..200 */
-
- /* Linear interpolation */
- cos_LSF_QA[ordering[k]] = silk_RSHIFT_ROUND( silk_LSHIFT( cos_val, 8 ) + silk_MUL( delta, f_frac ), 20 - QA ); /* QA */
- }
-
- dd = silk_RSHIFT( d, 1 );
-
- /* generate even and odd polynomials using convolution */
- silk_NLSF2A_find_poly( P, &cos_LSF_QA[ 0 ], dd );
- silk_NLSF2A_find_poly( Q, &cos_LSF_QA[ 1 ], dd );
-
- /* convert even and odd polynomials to opus_int32 Q12 filter coefs */
- for( k = 0; k < dd; k++ ) {
- Ptmp = P[ k+1 ] + P[ k ];
- Qtmp = Q[ k+1 ] - Q[ k ];
-
- /* the Ptmp and Qtmp values at this stage need to fit in int32 */
- a32_QA1[ k ] = -Qtmp - Ptmp; /* QA+1 */
- a32_QA1[ d-k-1 ] = Qtmp - Ptmp; /* QA+1 */
- }
-
- /* Limit the maximum absolute value of the prediction coefficients, so that they'll fit in int16 */
- for( i = 0; i < 10; i++ ) {
- /* Find maximum absolute value and its index */
- maxabs = 0;
- for( k = 0; k < d; k++ ) {
- absval = silk_abs( a32_QA1[k] );
- if( absval > maxabs ) {
- maxabs = absval;
- idx = k;
- }
- }
- maxabs = silk_RSHIFT_ROUND( maxabs, QA + 1 - 12 ); /* QA+1 -> Q12 */
-
- if( maxabs > silk_int16_MAX ) {
- /* Reduce magnitude of prediction coefficients */
- maxabs = silk_min( maxabs, 163838 ); /* ( silk_int32_MAX >> 14 ) + silk_int16_MAX = 163838 */
- sc_Q16 = SILK_FIX_CONST( 0.999, 16 ) - silk_DIV32( silk_LSHIFT( maxabs - silk_int16_MAX, 14 ),
- silk_RSHIFT32( silk_MUL( maxabs, idx + 1), 2 ) );
- silk_bwexpander_32( a32_QA1, d, sc_Q16 );
- } else {
- break;
- }
- }
-
- if( i == 10 ) {
- /* Reached the last iteration, clip the coefficients */
- for( k = 0; k < d; k++ ) {
- a_Q12[ k ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( a32_QA1[ k ], QA + 1 - 12 ) ); /* QA+1 -> Q12 */
- a32_QA1[ k ] = silk_LSHIFT( (opus_int32)a_Q12[ k ], QA + 1 - 12 );
- }
- } else {
- for( k = 0; k < d; k++ ) {
- a_Q12[ k ] = (opus_int16)silk_RSHIFT_ROUND( a32_QA1[ k ], QA + 1 - 12 ); /* QA+1 -> Q12 */
- }
- }
-
- for( i = 0; i < MAX_LPC_STABILIZE_ITERATIONS; i++ ) {
- if( silk_LPC_inverse_pred_gain( a_Q12, d ) < SILK_FIX_CONST( 1.0 / MAX_PREDICTION_POWER_GAIN, 30 ) ) {
- /* Prediction coefficients are (too close to) unstable; apply bandwidth expansion */
- /* on the unscaled coefficients, convert to Q12 and measure again */
- silk_bwexpander_32( a32_QA1, d, 65536 - silk_LSHIFT( 2, i ) );
- for( k = 0; k < d; k++ ) {
- a_Q12[ k ] = (opus_int16)silk_RSHIFT_ROUND( a32_QA1[ k ], QA + 1 - 12 ); /* QA+1 -> Q12 */
- }
- } else {
- break;
- }
- }
-}
-
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