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
|
/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#pragma once
#include <AK/ByteBuffer.h>
#include <AK/SharedBuffer.h>
#include <AK/Types.h>
#include <AK/Vector.h>
#include <string.h>
namespace Audio {
// A single sample in an audio buffer.
// Values are floating point, and should range from -1.0 to +1.0
struct Sample {
Sample()
: left(0)
, right(0)
{
}
// For mono
Sample(double left)
: left(left)
, right(left)
{
}
// For stereo
Sample(double left, double right)
: left(left)
, right(right)
{
}
void clip()
{
if (left > 1)
left = 1;
else if (left < -1)
left = -1;
if (right > 1)
right = 1;
else if (right < -1)
right = -1;
}
void scale(int percent)
{
double pct = (double)percent / 100.0;
left *= pct;
right *= pct;
}
Sample& operator+=(const Sample& other)
{
left += other.left;
right += other.right;
return *this;
}
double left;
double right;
};
// Small helper to resample from one playback rate to another
// This isn't really "smart", in that we just insert (or drop) samples.
// Should do better...
class ResampleHelper {
public:
ResampleHelper(double source, double target);
void process_sample(double sample_l, double sample_r);
bool read_sample(double& next_l, double& next_r);
private:
const double m_ratio;
double m_current_ratio { 0 };
double m_last_sample_l { 0 };
double m_last_sample_r { 0 };
};
// A buffer of audio samples, normalized to 44100hz.
class Buffer : public RefCounted<Buffer> {
public:
static RefPtr<Buffer> from_pcm_data(ByteBuffer& data, ResampleHelper& resampler, int num_channels, int bits_per_sample);
static NonnullRefPtr<Buffer> create_with_samples(Vector<Sample>&& samples)
{
return adopt(*new Buffer(move(samples)));
}
static NonnullRefPtr<Buffer> create_with_shared_buffer(NonnullRefPtr<SharedBuffer>&& buffer, int sample_count)
{
return adopt(*new Buffer(move(buffer), sample_count));
}
const Sample* samples() const { return (const Sample*)data(); }
int sample_count() const { return m_sample_count; }
const void* data() const { return m_buffer->data(); }
int size_in_bytes() const { return m_sample_count * (int)sizeof(Sample); }
int shbuf_id() const { return m_buffer->shbuf_id(); }
SharedBuffer& shared_buffer() { return *m_buffer; }
private:
explicit Buffer(Vector<Sample>&& samples)
: m_buffer(*SharedBuffer::create_with_size(samples.size() * sizeof(Sample)))
, m_sample_count(samples.size())
{
memcpy(m_buffer->data(), samples.data(), samples.size() * sizeof(Sample));
}
explicit Buffer(NonnullRefPtr<SharedBuffer>&& buffer, int sample_count)
: m_buffer(move(buffer))
, m_sample_count(sample_count)
{
}
NonnullRefPtr<SharedBuffer> m_buffer;
const int m_sample_count;
};
}
|
