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_SortSq.c
16
17 ******************************************************************/
18
19 #include "defines.h"
20
21 /*----------------------------------------------------------------*
22 * scalar quantization
23 *---------------------------------------------------------------*/
24
WebRtcIlbcfix_SortSq(int16_t * xq,int16_t * index,int16_t x,const int16_t * cb,int16_t cb_size)25 void WebRtcIlbcfix_SortSq(
26 int16_t *xq, /* (o) the quantized value */
27 int16_t *index, /* (o) the quantization index */
28 int16_t x, /* (i) the value to quantize */
29 const int16_t *cb, /* (i) the quantization codebook */
30 int16_t cb_size /* (i) the size of the quantization codebook */
31 ){
32 int i;
33
34 if (x <= cb[0]) {
35 *index = 0;
36 *xq = cb[0];
37 } else {
38 i = 0;
39 while ((x > cb[i]) && (i < (cb_size-1))) {
40 i++;
41 }
42
43 if (x > (((int32_t)cb[i] + cb[i - 1] + 1) >> 1)) {
44 *index = i;
45 *xq = cb[i];
46 } else {
47 *index = i - 1;
48 *xq = cb[i - 1];
49 }
50 }
51 }
52