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_LspInterpolate2PolyDec.c
16
17 ******************************************************************/
18
19 #include "modules/audio_coding/codecs/ilbc/interpolate.h"
20 #include "modules/audio_coding/codecs/ilbc/lsf_to_poly.h"
21 #include "modules/audio_coding/codecs/ilbc/defines.h"
22
23 /*----------------------------------------------------------------*
24 * interpolation of lsf coefficients for the decoder
25 *---------------------------------------------------------------*/
26
WebRtcIlbcfix_LspInterpolate2PolyDec(int16_t * a,int16_t * lsf1,int16_t * lsf2,int16_t coef,int16_t length)27 void WebRtcIlbcfix_LspInterpolate2PolyDec(
28 int16_t *a, /* (o) lpc coefficients Q12 */
29 int16_t *lsf1, /* (i) first set of lsf coefficients Q13 */
30 int16_t *lsf2, /* (i) second set of lsf coefficients Q13 */
31 int16_t coef, /* (i) weighting coefficient to use between
32 lsf1 and lsf2 Q14 */
33 int16_t length /* (i) length of coefficient vectors */
34 ){
35 int16_t lsftmp[LPC_FILTERORDER];
36
37 /* interpolate LSF */
38 WebRtcIlbcfix_Interpolate(lsftmp, lsf1, lsf2, coef, length);
39
40 /* Compute the filter coefficients from the LSF */
41 WebRtcIlbcfix_Lsf2Poly(a, lsftmp);
42 }
43