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_Interpolate.c 16 17 ******************************************************************/ 18 19 #include "defines.h" 20 #include "constants.h" 21 22 /*----------------------------------------------------------------* 23 * interpolation between vectors 24 *---------------------------------------------------------------*/ 25 26 void WebRtcIlbcfix_Interpolate( 27 int16_t *out, /* (o) output vector */ 28 int16_t *in1, /* (i) first input vector */ 29 int16_t *in2, /* (i) second input vector */ 30 int16_t coef, /* (i) weight coefficient in Q14 */ 31 int16_t length) /* (i) number of sample is vectors */ 32 { 33 int i; 34 int16_t invcoef; 35 36 /* 37 Performs the operation out[i] = in[i]*coef + (1-coef)*in2[i] (with rounding) 38 */ 39 40 invcoef = 16384 - coef; /* 16384 = 1.0 (Q14)*/ 41 for (i = 0; i < length; i++) { 42 out[i] = (int16_t) WEBRTC_SPL_RSHIFT_W32( 43 (WEBRTC_SPL_MUL_16_16(coef, in1[i]) + WEBRTC_SPL_MUL_16_16(invcoef, in2[i]))+8192, 44 14); 45 } 46 47 return; 48 } 49
