mirror of
https://github.com/oxen-io/session-android.git
synced 2024-12-04 15:35:19 +00:00
46 lines
1.5 KiB
C
46 lines
1.5 KiB
C
/*
|
|
* 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_GainDequant.c
|
|
|
|
******************************************************************/
|
|
|
|
#include "defines.h"
|
|
#include "constants.h"
|
|
|
|
/*----------------------------------------------------------------*
|
|
* decoder for quantized gains in the gain-shape coding of
|
|
* residual
|
|
*---------------------------------------------------------------*/
|
|
|
|
int16_t WebRtcIlbcfix_GainDequant(
|
|
/* (o) quantized gain value (Q14) */
|
|
int16_t index, /* (i) quantization index */
|
|
int16_t maxIn, /* (i) maximum of unquantized gain (Q14) */
|
|
int16_t stage /* (i) The stage of the search */
|
|
){
|
|
int16_t scale;
|
|
const int16_t *gain;
|
|
|
|
/* obtain correct scale factor */
|
|
|
|
scale=WEBRTC_SPL_ABS_W16(maxIn);
|
|
scale = WEBRTC_SPL_MAX(1638, scale); /* if lower than 0.1, set it to 0.1 */
|
|
|
|
/* select the quantization table and return the decoded value */
|
|
gain = WebRtcIlbcfix_kGain[stage];
|
|
|
|
return((int16_t)((WEBRTC_SPL_MUL_16_16(scale, gain[index])+8192)>>14));
|
|
}
|