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 "modules/audio_coding/codecs/ilbc/refiner.h"
20
21 #include "modules/audio_coding/codecs/ilbc/constants.h"
22 #include "modules/audio_coding/codecs/ilbc/enh_upsample.h"
23 #include "modules/audio_coding/codecs/ilbc/my_corr.h"
24
25 /*----------------------------------------------------------------*
26 * find segment starting near idata+estSegPos that has highest
27 * correlation with idata+centerStartPos through
28 * idata+centerStartPos+ENH_BLOCKL-1 segment is found at a
29 * resolution of ENH_UPSO times the original of the original
30 * sampling rate
31 *---------------------------------------------------------------*/
32
WebRtcIlbcfix_Refiner(size_t * updStartPos,int16_t * idata,size_t idatal,size_t centerStartPos,size_t estSegPos,int16_t * surround,int16_t gain)33 void WebRtcIlbcfix_Refiner(
34 size_t *updStartPos, /* (o) updated start point (Q-2) */
35 int16_t *idata, /* (i) original data buffer */
36 size_t idatal, /* (i) dimension of idata */
37 size_t centerStartPos, /* (i) beginning center segment */
38 size_t estSegPos, /* (i) estimated beginning other segment (Q-2) */
39 int16_t *surround, /* (i/o) The contribution from this sequence
40 summed with earlier contributions */
41 int16_t gain /* (i) Gain to use for this sequence */
42 ){
43 size_t estSegPosRounded, searchSegStartPos, searchSegEndPos, corrdim;
44 size_t tloc, tloc2, i;
45
46 int32_t maxtemp, scalefact;
47 int16_t *filtStatePtr, *polyPtr;
48 /* Stack based */
49 int16_t filt[7];
50 int32_t corrVecUps[ENH_CORRDIM*ENH_UPS0];
51 int32_t corrVecTemp[ENH_CORRDIM];
52 int16_t vect[ENH_VECTL];
53 int16_t corrVec[ENH_CORRDIM];
54
55 /* defining array bounds */
56
57 estSegPosRounded = (estSegPos - 2) >> 2;
58
59 searchSegStartPos =
60 (estSegPosRounded < ENH_SLOP) ? 0 : (estSegPosRounded - ENH_SLOP);
61
62 searchSegEndPos = estSegPosRounded + ENH_SLOP;
63 if ((searchSegEndPos + ENH_BLOCKL) >= idatal) {
64 searchSegEndPos = idatal - ENH_BLOCKL - 1;
65 }
66
67 corrdim = searchSegEndPos + 1 - searchSegStartPos;
68
69 /* compute upsampled correlation and find
70 location of max */
71
72 WebRtcIlbcfix_MyCorr(corrVecTemp, idata + searchSegStartPos,
73 corrdim + ENH_BLOCKL - 1, idata + centerStartPos,
74 ENH_BLOCKL);
75
76 /* Calculate the rescaling factor for the correlation in order to
77 put the correlation in a int16_t vector instead */
78 maxtemp = WebRtcSpl_MaxAbsValueW32(corrVecTemp, corrdim);
79
80 scalefact = WebRtcSpl_GetSizeInBits(maxtemp) - 15;
81
82 if (scalefact > 0) {
83 for (i = 0; i < corrdim; i++) {
84 corrVec[i] = (int16_t)(corrVecTemp[i] >> scalefact);
85 }
86 } else {
87 for (i = 0; i < corrdim; i++) {
88 corrVec[i] = (int16_t)corrVecTemp[i];
89 }
90 }
91 /* In order to guarantee that all values are initialized */
92 for (i = corrdim; i < ENH_CORRDIM; i++) {
93 corrVec[i] = 0;
94 }
95
96 /* Upsample the correlation */
97 WebRtcIlbcfix_EnhUpsample(corrVecUps, corrVec);
98
99 /* Find maximum */
100 tloc = WebRtcSpl_MaxIndexW32(corrVecUps, ENH_UPS0 * corrdim);
101
102 /* make vector can be upsampled without ever running outside
103 bounds */
104 *updStartPos = searchSegStartPos * 4 + tloc + 4;
105
106 tloc2 = (tloc + 3) >> 2;
107
108 /* initialize the vector to be filtered, stuff with zeros
109 when data is outside idata buffer */
110 if (ENH_FL0 > (searchSegStartPos + tloc2)) {
111 const size_t st = ENH_FL0 - searchSegStartPos - tloc2;
112 WebRtcSpl_MemSetW16(vect, 0, st);
113 WEBRTC_SPL_MEMCPY_W16(&vect[st], idata, ENH_VECTL - st);
114 } else {
115 const size_t st = searchSegStartPos + tloc2 - ENH_FL0;
116 if ((st + ENH_VECTL) > idatal) {
117 const size_t en = st + ENH_VECTL - idatal;
118 WEBRTC_SPL_MEMCPY_W16(vect, &idata[st], ENH_VECTL - en);
119 WebRtcSpl_MemSetW16(&vect[ENH_VECTL - en], 0, en);
120 } else {
121 WEBRTC_SPL_MEMCPY_W16(vect, &idata[st], ENH_VECTL);
122 }
123 }
124
125 /* compute the segment (this is actually a convolution) */
126 filtStatePtr = filt + 6;
127 polyPtr = (int16_t*)WebRtcIlbcfix_kEnhPolyPhaser[tloc2 * ENH_UPS0 - tloc];
128 for (i = 0; i < 7; i++) {
129 *filtStatePtr-- = *polyPtr++;
130 }
131
132 WebRtcSpl_FilterMAFastQ12(&vect[6], vect, filt, ENH_FLO_MULT2_PLUS1,
133 ENH_BLOCKL);
134
135 /* Add the contribution from this vector (scaled with gain) to the total
136 surround vector */
137 WebRtcSpl_AddAffineVectorToVector(surround, vect, gain, 32768, 16,
138 ENH_BLOCKL);
139
140 return;
141 }
142