1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
|
/*############################################################################*/
/*# #*/
/*# Ambisonic C++ Library #*/
/*# CAmbisonicSource - Ambisonic Source #*/
/*# Copyright © 2007 Aristotel Digenis #*/
/*# Copyright © 2017 Videolabs #*/
/*# #*/
/*# Filename: AmbisonicSource.cpp #*/
/*# Version: 0.2 #*/
/*# Date: 19/05/2007 #*/
/*# Author(s): Aristotel Digenis #*/
/*# Licence: LGPL #*/
/*# #*/
/*############################################################################*/
#include "AmbisonicSource.h"
#define fSqrt32 sqrt(3.f)/2.f
#define fSqrt58 sqrt(5.f/8.f)
#define fSqrt152 sqrt(15.f)/2.f
#define fSqrt38 sqrt(3.f/8.f)
CAmbisonicSource::CAmbisonicSource()
{
m_polPosition.fAzimuth = 0.f;
m_polPosition.fElevation = 0.f;
m_polPosition.fDistance = 1.f;
m_fGain = 1.f;
}
bool CAmbisonicSource::Configure(unsigned nOrder, bool b3D, unsigned nMisc)
{
bool success = CAmbisonicBase::Configure(nOrder, b3D, nMisc);
if(!success)
return false;
m_pfCoeff.resize( m_nChannelCount, 0 );
// for a Basic Ambisonics decoder all of the gains are set to 1.f
m_pfOrderWeights.resize( m_nOrder + 1, 1.f );
return true;
}
void CAmbisonicSource::Reset()
{
//memset(m_pfCoeff, 0, m_nChannelCount * sizeof(float));
}
void CAmbisonicSource::Refresh()
{
float fCosAzim = cosf(m_polPosition.fAzimuth);
float fSinAzim = sinf(m_polPosition.fAzimuth);
float fCosElev = cosf(m_polPosition.fElevation);
float fSinElev = sinf(m_polPosition.fElevation);
float fCos2Azim = cosf(2.f * m_polPosition.fAzimuth);
float fSin2Azim = sinf(2.f * m_polPosition.fAzimuth);
float fSin2Elev = sinf(2.f * m_polPosition.fElevation);
if(m_b3D)
{
// Uses ACN channel ordering and SN3D normalization scheme (AmbiX format)
if(m_nOrder >= 0)
{
m_pfCoeff[0] = 1.f * m_pfOrderWeights[0]; // W
}
if(m_nOrder >= 1)
{
m_pfCoeff[1] = (fSinAzim * fCosElev) * m_pfOrderWeights[1]; // Y
m_pfCoeff[2] = (fSinElev) * m_pfOrderWeights[1]; // Z
m_pfCoeff[3] = (fCosAzim * fCosElev) * m_pfOrderWeights[1]; // X
}
if(m_nOrder >= 2)
{
m_pfCoeff[4] = fSqrt32*(fSin2Azim * powf(fCosElev, 2)) * m_pfOrderWeights[2]; // V
m_pfCoeff[5] = fSqrt32*(fSinAzim * fSin2Elev) * m_pfOrderWeights[2]; // T
m_pfCoeff[6] = (1.5f * powf(fSinElev, 2.f) - 0.5f) * m_pfOrderWeights[2]; // R
m_pfCoeff[7] = fSqrt32*(fCosAzim * fSin2Elev) * m_pfOrderWeights[2]; // S
m_pfCoeff[8] = fSqrt32*(fCos2Azim * powf(fCosElev, 2)) * m_pfOrderWeights[2]; // U
}
if(m_nOrder >= 3)
{
m_pfCoeff[9] = fSqrt58*(sinf(3.f * m_polPosition.fAzimuth) * powf(fCosElev, 3.f)) * m_pfOrderWeights[3]; // Q
m_pfCoeff[10] = fSqrt152*(fSin2Azim * fSinElev * powf(fCosElev, 2.f)) * m_pfOrderWeights[3]; // O
m_pfCoeff[11] = fSqrt38*(fSinAzim * fCosElev * (5.f * powf(fSinElev, 2.f) - 1.f)) * m_pfOrderWeights[3]; // M
m_pfCoeff[12] = (fSinElev * (5.f * powf(fSinElev, 2.f) - 3.f) * 0.5f) * m_pfOrderWeights[3]; // K
m_pfCoeff[13] = fSqrt38*(fCosAzim * fCosElev * (5.f * powf(fSinElev, 2.f) - 1.f)) * m_pfOrderWeights[3]; // L
m_pfCoeff[14] = fSqrt152*(fCos2Azim * fSinElev * powf(fCosElev, 2.f)) * m_pfOrderWeights[3]; // N
m_pfCoeff[15] = fSqrt58*(cosf(3.f * m_polPosition.fAzimuth) * powf(fCosElev, 3.f)) * m_pfOrderWeights[3]; // P
}
}
else
{
if(m_nOrder >= 0)
{
m_pfCoeff[0] = m_pfOrderWeights[0];
}
if(m_nOrder >= 1)
{
m_pfCoeff[1] = (fCosAzim * fCosElev) * m_pfOrderWeights[1];
m_pfCoeff[2] = (fSinAzim * fCosElev) * m_pfOrderWeights[1];
}
if(m_nOrder >= 2)
{
m_pfCoeff[3] = (fCos2Azim * powf(fCosElev, 2)) * m_pfOrderWeights[2];
m_pfCoeff[4] = (fSin2Azim * powf(fCosElev, 2)) * m_pfOrderWeights[2];
}
if(m_nOrder >= 3)
{
m_pfCoeff[5] = (cosf(3.f * m_polPosition.fAzimuth) * powf(fCosElev, 3.f)) * m_pfOrderWeights[3];
m_pfCoeff[6] = (sinf(3.f * m_polPosition.fAzimuth) * powf(fCosElev, 3.f)) * m_pfOrderWeights[3];
}
}
for(unsigned ni = 0; ni < m_nChannelCount; ni++)
m_pfCoeff[ni] *= m_fGain;
}
void CAmbisonicSource::SetPosition(PolarPoint polPosition)
{
m_polPosition = polPosition;
}
PolarPoint CAmbisonicSource::GetPosition()
{
return m_polPosition;
}
void CAmbisonicSource::SetOrderWeight(unsigned nOrder, float fWeight)
{
m_pfOrderWeights[nOrder] = fWeight;
}
void CAmbisonicSource::SetOrderWeightAll(float fWeight)
{
for(unsigned niOrder = 0; niOrder < m_nOrder + 1; niOrder++)
{
m_pfOrderWeights[niOrder] = fWeight;
}
}
void CAmbisonicSource::SetCoefficient(unsigned nChannel, float fCoeff)
{
m_pfCoeff[nChannel] = fCoeff;
}
float CAmbisonicSource::GetOrderWeight(unsigned nOrder)
{
return m_pfOrderWeights[nOrder];
}
float CAmbisonicSource::GetCoefficient(unsigned nChannel)
{
return m_pfCoeff[nChannel];
}
void CAmbisonicSource::SetGain(float fGain)
{
m_fGain = fGain;
}
float CAmbisonicSource::GetGain()
{
return m_fGain;
}
|
