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
|
/*
* Copyright (C) 2003-2009 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.
*/
#ifndef MPD_AUDIO_FORMAT_H
#define MPD_AUDIO_FORMAT_H
#include <stdint.h>
#include <stdbool.h>
struct audio_format {
uint32_t sample_rate;
uint8_t bits;
uint8_t channels;
uint8_t reverse_endian;
};
static inline void audio_format_clear(struct audio_format *af)
{
af->sample_rate = 0;
af->bits = 0;
af->channels = 0;
af->reverse_endian = 0;
}
static inline void audio_format_init(struct audio_format *af,
uint32_t sample_rate,
uint8_t bits, uint8_t channels)
{
af->sample_rate = sample_rate;
af->bits = bits;
af->channels = channels;
}
static inline bool audio_format_defined(const struct audio_format *af)
{
return af->sample_rate != 0;
}
/**
* Checks whether the sample rate is valid.
*
* @param sample_rate the sample rate in Hz
*/
static inline bool
audio_valid_sample_rate(unsigned sample_rate)
{
return sample_rate > 0 && sample_rate < (1 << 30);
}
/**
* Checks whether the sample format is valid.
*
* @param bits the number of significant bits per sample
*/
static inline bool
audio_valid_sample_format(unsigned bits)
{
return bits == 16 || bits == 24 || bits == 32 || bits == 8;
}
/**
* Checks whether the number of channels is valid.
*/
static inline bool
audio_valid_channel_count(unsigned channels)
{
return channels >= 1 && channels <= 8;
}
/**
* Returns false if the format is not valid for playback with MPD.
* This function performs some basic validity checks.
*/
static inline bool audio_format_valid(const struct audio_format *af)
{
return audio_valid_sample_rate(af->sample_rate) &&
audio_valid_sample_format(af->bits) &&
audio_valid_channel_count(af->channels);
}
static inline bool audio_format_equals(const struct audio_format *a,
const struct audio_format *b)
{
return a->sample_rate == b->sample_rate &&
a->bits == b->bits &&
a->channels == b->channels &&
a->reverse_endian == b->reverse_endian;
}
/**
* Returns the size of each (mono) sample in bytes.
*/
static inline unsigned audio_format_sample_size(const struct audio_format *af)
{
if (af->bits <= 8)
return 1;
else if (af->bits <= 16)
return 2;
else
return 4;
}
static inline unsigned
audio_format_frame_size(const struct audio_format *af)
{
return audio_format_sample_size(af) * af->channels;
}
static inline double audio_format_time_to_size(const struct audio_format *af)
{
return af->sample_rate * audio_format_frame_size(af);
}
static inline double audioFormatSizeToTime(const struct audio_format *af)
{
return 1.0 / audio_format_time_to_size(af);
}
#endif
|
