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_Refiner.c
16
17******************************************************************/
18
19#include "defines.h"
20#include "constants.h"
21#include "enh_upsample.h"
22#include "my_corr.h"
23
24/*----------------------------------------------------------------*
25 * find segment starting near idata+estSegPos that has highest
26 * correlation with idata+centerStartPos through
27 * idata+centerStartPos+ENH_BLOCKL-1 segment is found at a
28 * resolution of ENH_UPSO times the original of the original
29 * sampling rate
30 *---------------------------------------------------------------*/
31
32void WebRtcIlbcfix_Refiner(
33    size_t *updStartPos, /* (o) updated start point (Q-2) */
34    int16_t *idata,   /* (i) original data buffer */
35    size_t idatal,   /* (i) dimension of idata */
36    size_t centerStartPos, /* (i) beginning center segment */
37    size_t estSegPos,  /* (i) estimated beginning other segment (Q-2) */
38    int16_t *surround,  /* (i/o) The contribution from this sequence
39                                           summed with earlier contributions */
40    int16_t gain    /* (i) Gain to use for this sequence */
41                           ){
42  size_t estSegPosRounded, searchSegStartPos, searchSegEndPos, corrdim;
43  size_t tloc, tloc2, i;
44
45  int32_t maxtemp, scalefact;
46  int16_t *filtStatePtr, *polyPtr;
47  /* Stack based */
48  int16_t filt[7];
49  int32_t corrVecUps[ENH_CORRDIM*ENH_UPS0];
50  int32_t corrVecTemp[ENH_CORRDIM];
51  int16_t vect[ENH_VECTL];
52  int16_t corrVec[ENH_CORRDIM];
53
54  /* defining array bounds */
55
56  estSegPosRounded = (estSegPos - 2) >> 2;
57
58  searchSegStartPos =
59      (estSegPosRounded < ENH_SLOP) ? 0 : (estSegPosRounded - ENH_SLOP);
60
61  searchSegEndPos = estSegPosRounded + ENH_SLOP;
62  if ((searchSegEndPos + ENH_BLOCKL) >= idatal) {
63    searchSegEndPos = idatal - ENH_BLOCKL - 1;
64  }
65
66  corrdim = searchSegEndPos + 1 - searchSegStartPos;
67
68  /* compute upsampled correlation and find
69     location of max */
70
71  WebRtcIlbcfix_MyCorr(corrVecTemp, idata + searchSegStartPos,
72                       corrdim + ENH_BLOCKL - 1, idata + centerStartPos,
73                       ENH_BLOCKL);
74
75  /* Calculate the rescaling factor for the correlation in order to
76     put the correlation in a int16_t vector instead */
77  maxtemp = WebRtcSpl_MaxAbsValueW32(corrVecTemp, corrdim);
78
79  scalefact = WebRtcSpl_GetSizeInBits(maxtemp) - 15;
80
81  if (scalefact > 0) {
82    for (i = 0; i < corrdim; i++) {
83      corrVec[i] = (int16_t)(corrVecTemp[i] >> scalefact);
84    }
85  } else {
86    for (i = 0; i < corrdim; i++) {
87      corrVec[i] = (int16_t)corrVecTemp[i];
88    }
89  }
90  /* In order to guarantee that all values are initialized */
91  for (i = corrdim; i < ENH_CORRDIM; i++) {
92    corrVec[i] = 0;
93  }
94
95  /* Upsample the correlation */
96  WebRtcIlbcfix_EnhUpsample(corrVecUps, corrVec);
97
98  /* Find maximum */
99  tloc = WebRtcSpl_MaxIndexW32(corrVecUps, ENH_UPS0 * corrdim);
100
101  /* make vector can be upsampled without ever running outside
102     bounds */
103  *updStartPos = searchSegStartPos * 4 + tloc + 4;
104
105  tloc2 = (tloc + 3) >> 2;
106
107  /* initialize the vector to be filtered, stuff with zeros
108     when data is outside idata buffer */
109  if (ENH_FL0 > (searchSegStartPos + tloc2)) {
110    const size_t st = ENH_FL0 - searchSegStartPos - tloc2;
111    WebRtcSpl_MemSetW16(vect, 0, st);
112    WEBRTC_SPL_MEMCPY_W16(&vect[st], idata, ENH_VECTL - st);
113  } else {
114    const size_t st = searchSegStartPos + tloc2 - ENH_FL0;
115    if ((st + ENH_VECTL) > idatal) {
116      const size_t en = st + ENH_VECTL - idatal;
117      WEBRTC_SPL_MEMCPY_W16(vect, &idata[st], ENH_VECTL - en);
118      WebRtcSpl_MemSetW16(&vect[ENH_VECTL - en], 0, en);
119    } else {
120      WEBRTC_SPL_MEMCPY_W16(vect, &idata[st], ENH_VECTL);
121    }
122  }
123
124  /* compute the segment (this is actually a convolution) */
125  filtStatePtr = filt + 6;
126  polyPtr = (int16_t*)WebRtcIlbcfix_kEnhPolyPhaser[tloc2 * ENH_UPS0 - tloc];
127  for (i = 0; i < 7; i++) {
128    *filtStatePtr-- = *polyPtr++;
129  }
130
131  WebRtcSpl_FilterMAFastQ12(&vect[6], vect, filt, ENH_FLO_MULT2_PLUS1,
132                            ENH_BLOCKL);
133
134  /* Add the contribution from this vector (scaled with gain) to the total
135     surround vector */
136  WebRtcSpl_AddAffineVectorToVector(surround, vect, gain, 32768, 16,
137                                    ENH_BLOCKL);
138
139  return;
140}
141