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
168
169
170
171
172
173
174
175
176
177
178
179
180
181
|
/*
* Copyright (C) 2003-2013 The Music Player Daemon Project
* http://www.musicpd.org
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "config.h"
#include "PcmChannels.hxx"
#include "PcmBuffer.hxx"
#include "Traits.hxx"
#include "AudioFormat.hxx"
#include "util/ConstBuffer.hxx"
#include <assert.h>
template<typename D, typename S>
static void
MonoToStereo(D dest, S src, S end)
{
while (src != end) {
const auto value = *src++;
*dest++ = value;
*dest++ = value;
}
}
template<SampleFormat F, class Traits=SampleTraits<F>>
static typename Traits::value_type
StereoToMono(typename Traits::value_type _a,
typename Traits::value_type _b)
{
typename Traits::sum_type a(_a);
typename Traits::sum_type b(_b);
return typename Traits::value_type((a + b) / 2);
}
template<SampleFormat F, class Traits=SampleTraits<F>>
static typename Traits::pointer_type
StereoToMono(typename Traits::pointer_type dest,
typename Traits::const_pointer_type src,
typename Traits::const_pointer_type end)
{
while (src != end) {
const auto a = *src++;
const auto b = *src++;
*dest++ = StereoToMono<F, Traits>(a, b);
}
return dest;
}
template<SampleFormat F, class Traits=SampleTraits<F>>
static typename Traits::pointer_type
NToStereo(typename Traits::pointer_type dest,
unsigned src_channels,
typename Traits::const_pointer_type src,
typename Traits::const_pointer_type end)
{
assert((end - src) % src_channels == 0);
while (src != end) {
typename Traits::sum_type sum = *src++;
for (unsigned c = 1; c < src_channels; ++c)
sum += *src++;
typename Traits::value_type value(sum / int(src_channels));
/* TODO: this is actually only mono ... */
*dest++ = value;
*dest++ = value;
}
return dest;
}
template<SampleFormat F, class Traits=SampleTraits<F>>
static typename Traits::pointer_type
NToM(typename Traits::pointer_type dest,
unsigned dest_channels,
unsigned src_channels,
typename Traits::const_pointer_type src,
typename Traits::const_pointer_type end)
{
assert((end - src) % src_channels == 0);
while (src != end) {
typename Traits::sum_type sum = *src++;
for (unsigned c = 1; c < src_channels; ++c)
sum += *src++;
typename Traits::value_type value(sum / int(src_channels));
/* TODO: this is actually only mono ... */
for (unsigned c = 0; c < dest_channels; ++c)
*dest++ = value;
}
return dest;
}
template<SampleFormat F, class Traits=SampleTraits<F>>
static ConstBuffer<typename Traits::value_type>
ConvertChannels(PcmBuffer &buffer,
unsigned dest_channels,
unsigned src_channels,
ConstBuffer<typename Traits::value_type> src)
{
assert(src.size % src_channels == 0);
const size_t dest_size = src.size / src_channels * dest_channels;
auto dest = buffer.GetT<typename Traits::value_type>(dest_size);
if (src_channels == 1 && dest_channels == 2)
MonoToStereo(dest, src.begin(), src.end());
else if (src_channels == 2 && dest_channels == 1)
StereoToMono<F>(dest, src.begin(), src.end());
else if (dest_channels == 2)
NToStereo<F>(dest, src_channels, src.begin(), src.end());
else
NToM<F>(dest, dest_channels,
src_channels, src.begin(), src.end());
return { dest, dest_size };
}
ConstBuffer<int16_t>
pcm_convert_channels_16(PcmBuffer &buffer,
unsigned dest_channels,
unsigned src_channels,
ConstBuffer<int16_t> src)
{
return ConvertChannels<SampleFormat::S16>(buffer, dest_channels,
src_channels, src);
}
ConstBuffer<int32_t>
pcm_convert_channels_24(PcmBuffer &buffer,
unsigned dest_channels,
unsigned src_channels,
ConstBuffer<int32_t> src)
{
return ConvertChannels<SampleFormat::S24_P32>(buffer, dest_channels,
src_channels, src);
}
ConstBuffer<int32_t>
pcm_convert_channels_32(PcmBuffer &buffer,
unsigned dest_channels,
unsigned src_channels,
ConstBuffer<int32_t> src)
{
return ConvertChannels<SampleFormat::S32>(buffer, dest_channels,
src_channels, src);
}
ConstBuffer<float>
pcm_convert_channels_float(PcmBuffer &buffer,
unsigned dest_channels,
unsigned src_channels,
ConstBuffer<float> src)
{
return ConvertChannels<SampleFormat::FLOAT>(buffer, dest_channels,
src_channels, src);
}
|
