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_AbsQuantLoop.c
16
17 ******************************************************************/
18
19 #include "modules/audio_coding/codecs/ilbc/defines.h"
20 #include "modules/audio_coding/codecs/ilbc/constants.h"
21 #include "modules/audio_coding/codecs/ilbc/sort_sq.h"
22
WebRtcIlbcfix_AbsQuantLoop(int16_t * syntOutIN,int16_t * in_weightedIN,int16_t * weightDenumIN,size_t * quantLenIN,int16_t * idxVecIN)23 void WebRtcIlbcfix_AbsQuantLoop(int16_t *syntOutIN, int16_t *in_weightedIN,
24 int16_t *weightDenumIN, size_t *quantLenIN,
25 int16_t *idxVecIN ) {
26 size_t k1, k2;
27 int16_t index;
28 int32_t toQW32;
29 int32_t toQ32;
30 int16_t tmp16a;
31 int16_t xq;
32
33 int16_t *syntOut = syntOutIN;
34 int16_t *in_weighted = in_weightedIN;
35 int16_t *weightDenum = weightDenumIN;
36 size_t *quantLen = quantLenIN;
37 int16_t *idxVec = idxVecIN;
38
39 for(k1=0;k1<2;k1++) {
40 for(k2=0;k2<quantLen[k1];k2++){
41
42 /* Filter to get the predicted value */
43 WebRtcSpl_FilterARFastQ12(
44 syntOut, syntOut,
45 weightDenum, LPC_FILTERORDER+1, 1);
46
47 /* the quantizer */
48 toQW32 = (int32_t)(*in_weighted) - (int32_t)(*syntOut);
49
50 toQ32 = (((int32_t)toQW32)<<2);
51
52 if (toQ32 > 32767) {
53 toQ32 = (int32_t) 32767;
54 } else if (toQ32 < -32768) {
55 toQ32 = (int32_t) -32768;
56 }
57
58 /* Quantize the state */
59 if (toQW32<(-7577)) {
60 /* To prevent negative overflow */
61 index=0;
62 } else if (toQW32>8151) {
63 /* To prevent positive overflow */
64 index=7;
65 } else {
66 /* Find the best quantization index
67 (state_sq3Tbl is in Q13 and toQ is in Q11)
68 */
69 WebRtcIlbcfix_SortSq(&xq, &index,
70 (int16_t)toQ32,
71 WebRtcIlbcfix_kStateSq3, 8);
72 }
73
74 /* Store selected index */
75 (*idxVec++) = index;
76
77 /* Compute decoded sample and update of the prediction filter */
78 tmp16a = ((WebRtcIlbcfix_kStateSq3[index] + 2 ) >> 2);
79
80 *syntOut = (int16_t) (tmp16a + (int32_t)(*in_weighted) - toQW32);
81
82 syntOut++; in_weighted++;
83 }
84 /* Update perceptual weighting filter at subframe border */
85 weightDenum += 11;
86 }
87 }
88