1 /*
2 * Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
3 *
4 * Use of this source code is governed by a BSD-style license
5 * that can be found in the LICENSE file in the root of the source
6 * tree. An additional intellectual property rights grant can be found
7 * in the file PATENTS. All contributing project authors may
8 * be found in the AUTHORS file in the root of the source tree.
9 */
10
11 /******************************************************************
12
13 iLBC Speech Coder ANSI-C Source Code
14
15 WebRtcIlbcfix_LsfInterpolate2PloyEnc.c
16
17 ******************************************************************/
18
19 #include "defines.h"
20 #include "interpolate.h"
21 #include "lsf_to_poly.h"
22
23 /*----------------------------------------------------------------*
24 * lsf interpolator and conversion from lsf to a coefficients
25 * (subrutine to SimpleInterpolateLSF)
26 *---------------------------------------------------------------*/
27
WebRtcIlbcfix_LsfInterpolate2PloyEnc(int16_t * a,int16_t * lsf1,int16_t * lsf2,int16_t coef,int16_t length)28 void WebRtcIlbcfix_LsfInterpolate2PloyEnc(
29 int16_t *a, /* (o) lpc coefficients Q12 */
30 int16_t *lsf1, /* (i) first set of lsf coefficients Q13 */
31 int16_t *lsf2, /* (i) second set of lsf coefficients Q13 */
32 int16_t coef, /* (i) weighting coefficient to use between
33 lsf1 and lsf2 Q14 */
34 int16_t length /* (i) length of coefficient vectors */
35 ) {
36 /* Stack based */
37 int16_t lsftmp[LPC_FILTERORDER];
38
39 /* interpolate LSF */
40 WebRtcIlbcfix_Interpolate(lsftmp, lsf1, lsf2, coef, length);
41
42 /* Compute the filter coefficients from the LSF */
43 WebRtcIlbcfix_Lsf2Poly(a, lsftmp);
44
45 return;
46 }
47