1 /*
2 ** Copyright 2003-2010, VisualOn, Inc.
3 **
4 ** Licensed under the Apache License, Version 2.0 (the "License");
5 ** you may not use this file except in compliance with the License.
6 ** You may obtain a copy of the License at
7 **
8 ** http://www.apache.org/licenses/LICENSE-2.0
9 **
10 ** Unless required by applicable law or agreed to in writing, software
11 ** distributed under the License is distributed on an "AS IS" BASIS,
12 ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 ** See the License for the specific language governing permissions and
14 ** limitations under the License.
15 */
16 /*******************************************************************************
17 File: ms_stereo.c
18
19 Content: MS stereo processing function
20
21 *******************************************************************************/
22
23 #include "basic_op.h"
24 #include "oper_32b.h"
25 #include "psy_const.h"
26 #include "ms_stereo.h"
27
28
29 /********************************************************************************
30 *
31 * function name: MsStereoProcessing
32 * description: detect use ms stereo or not
33 * if ((min(thrLn, thrRn)*min(thrLn, thrRn))/(enMn*enSn))
34 * >= ((thrLn *thrRn)/(enLn*enRn)) then ms stereo
35 *
36 **********************************************************************************/
MsStereoProcessing(Word32 * sfbEnergyLeft,Word32 * sfbEnergyRight,const Word32 * sfbEnergyMid,const Word32 * sfbEnergySide,Word32 * mdctSpectrumLeft,Word32 * mdctSpectrumRight,Word32 * sfbThresholdLeft,Word32 * sfbThresholdRight,Word32 * sfbSpreadedEnLeft,Word32 * sfbSpreadedEnRight,Word16 * msDigest,Word16 * msMask,const Word16 sfbCnt,const Word16 sfbPerGroup,const Word16 maxSfbPerGroup,const Word16 * sfbOffset)37 void MsStereoProcessing(Word32 *sfbEnergyLeft,
38 Word32 *sfbEnergyRight,
39 const Word32 *sfbEnergyMid,
40 const Word32 *sfbEnergySide,
41 Word32 *mdctSpectrumLeft,
42 Word32 *mdctSpectrumRight,
43 Word32 *sfbThresholdLeft,
44 Word32 *sfbThresholdRight,
45 Word32 *sfbSpreadedEnLeft,
46 Word32 *sfbSpreadedEnRight,
47 Word16 *msDigest,
48 Word16 *msMask,
49 const Word16 sfbCnt,
50 const Word16 sfbPerGroup,
51 const Word16 maxSfbPerGroup,
52 const Word16 *sfbOffset) {
53 Word32 sfb,sfboffs, j;
54 Word32 msMaskTrueSomewhere = 0;
55 Word32 msMaskFalseSomewhere = 0;
56
57 for (sfb=0; sfb<sfbCnt; sfb+=sfbPerGroup) {
58 for (sfboffs=0;sfboffs<maxSfbPerGroup;sfboffs++) {
59
60 Word32 temp;
61 Word32 pnlr,pnms;
62 Word32 minThreshold;
63 Word32 thrL, thrR, nrgL, nrgR;
64 Word32 idx, shift;
65
66 idx = sfb + sfboffs;
67
68 thrL = sfbThresholdLeft[idx];
69 thrR = sfbThresholdRight[idx];
70 nrgL = sfbEnergyLeft[idx];
71 nrgR = sfbEnergyRight[idx];
72
73 minThreshold = min(thrL, thrR);
74
75 nrgL = max(nrgL,thrL) + 1;
76 shift = norm_l(nrgL);
77 nrgL = Div_32(thrL << shift, nrgL << shift);
78 nrgR = max(nrgR,thrR) + 1;
79 shift = norm_l(nrgR);
80 nrgR = Div_32(thrR << shift, nrgR << shift);
81
82 pnlr = fixmul(nrgL, nrgR);
83
84 nrgL = sfbEnergyMid[idx];
85 nrgR = sfbEnergySide[idx];
86
87 nrgL = max(nrgL,minThreshold) + 1;
88 shift = norm_l(nrgL);
89 nrgL = Div_32(minThreshold << shift, nrgL << shift);
90
91 nrgR = max(nrgR,minThreshold) + 1;
92 shift = norm_l(nrgR);
93 nrgR = Div_32(minThreshold << shift, nrgR << shift);
94
95 pnms = fixmul(nrgL, nrgR);
96
97 temp = (pnlr + 1) / ((pnms >> 8) + 1);
98
99 temp = pnms - pnlr;
100 if( temp > 0 ){
101
102 msMask[idx] = 1;
103 msMaskTrueSomewhere = 1;
104
105 for (j=sfbOffset[idx]; j<sfbOffset[idx+1]; j++) {
106 Word32 left, right;
107 left = (mdctSpectrumLeft[j] >> 1);
108 right = (mdctSpectrumRight[j] >> 1);
109 mdctSpectrumLeft[j] = left + right;
110 mdctSpectrumRight[j] = left - right;
111 }
112
113 sfbThresholdLeft[idx] = minThreshold;
114 sfbThresholdRight[idx] = minThreshold;
115 sfbEnergyLeft[idx] = sfbEnergyMid[idx];
116 sfbEnergyRight[idx] = sfbEnergySide[idx];
117
118 sfbSpreadedEnRight[idx] = min(sfbSpreadedEnLeft[idx],sfbSpreadedEnRight[idx]) >> 1;
119 sfbSpreadedEnLeft[idx] = sfbSpreadedEnRight[idx];
120
121 }
122 else {
123 msMask[idx] = 0;
124 msMaskFalseSomewhere = 1;
125 }
126 }
127 if ( msMaskTrueSomewhere ) {
128 if(msMaskFalseSomewhere ) {
129 *msDigest = SI_MS_MASK_SOME;
130 } else {
131 *msDigest = SI_MS_MASK_ALL;
132 }
133 } else {
134 *msDigest = SI_MS_MASK_NONE;
135 }
136 }
137
138 }
139