blob: 17ed244bd43d448ef3c0c565a9bd5adb7513b1ad [file] [log] [blame]
/*
* Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
/******************************************************************
iLBC Speech Coder ANSI-C Source Code
WebRtcIlbcfix_Interpolate.c
******************************************************************/
#include "modules/audio_coding/codecs/ilbc/interpolate.h"
#include "modules/audio_coding/codecs/ilbc/constants.h"
#include "modules/audio_coding/codecs/ilbc/defines.h"
/*----------------------------------------------------------------*
* interpolation between vectors
*---------------------------------------------------------------*/
void WebRtcIlbcfix_Interpolate(
int16_t *out, /* (o) output vector */
int16_t *in1, /* (i) first input vector */
int16_t *in2, /* (i) second input vector */
int16_t coef, /* (i) weight coefficient in Q14 */
int16_t length) /* (i) number of sample is vectors */
{
int i;
int16_t invcoef;
/*
Performs the operation out[i] = in[i]*coef + (1-coef)*in2[i] (with rounding)
*/
invcoef = 16384 - coef; /* 16384 = 1.0 (Q14)*/
for (i = 0; i < length; i++) {
out[i] = (int16_t)((coef * in1[i] + invcoef * in2[i] + 8192) >> 14);
}
return;
}