summaryrefslogtreecommitdiff
path: root/polyp/sample.h
blob: a02a50feccbc31034b4615cf28e9b64522e7e346 (plain)
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
#ifndef foosamplehfoo
#define foosamplehfoo

/* $Id$ */

/***
  This file is part of polypaudio.
 
  polypaudio 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.
 
  polypaudio 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 polypaudio; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  USA.
***/

#include <inttypes.h>
#include <sys/types.h>
#include <math.h>

#include "cdecl.h"

/** \file
 * Constants and routines for sample type handling */

PA_C_DECL_BEGIN

/** Sample format */
enum pa_sample_format {
    PA_SAMPLE_U8,              /**< Unsigned 8 Bit PCM */
    PA_SAMPLE_ALAW,            /**< 8 Bit a-Law */
    PA_SAMPLE_ULAW,            /**< 8 Bit mu-Law */
    PA_SAMPLE_S16LE,           /**< Signed 16 Bit PCM, little endian (PC) */
    PA_SAMPLE_S16BE,           /**< Signed 16 Bit PCM, big endian */
    PA_SAMPLE_FLOAT32LE,       /**< 32 Bit IEEE floating point, little endian, range -1..1 */
    PA_SAMPLE_FLOAT32BE,       /**< 32 Bit IEEE floating point, big endian, range -1..1 */
    PA_SAMPLE_MAX,             /**< Upper limit of valid sample types */
    PA_SAMPLE_INVALID = -1     /**< An invalid value */
};

#ifdef WORDS_BIGENDIAN
/** Signed 16 Bit PCM, native endian */
#define PA_SAMPLE_S16NE PA_SAMPLE_S16BE
/** 32 Bit IEEE floating point, native endian */
#define PA_SAMPLE_FLOAT32NE PA_SAMPLE_FLOAT32BE
#else
/** Signed 16 Bit PCM, native endian */
#define PA_SAMPLE_S16NE PA_SAMPLE_S16LE
/** 32 Bit IEEE floating point, native endian */
#define PA_SAMPLE_FLOAT32NE PA_SAMPLE_FLOAT32LE
#endif

/** A Shortcut for PA_SAMPLE_FLOAT32NE */
#define PA_SAMPLE_FLOAT32 PA_SAMPLE_FLOAT32NE

/** A sample format and attribute specification */
struct pa_sample_spec {
    enum pa_sample_format format;  /**< The sample format */
    uint32_t rate;                 /**< The sample rate. (e.g. 44100) */
    uint8_t channels;              /**< Audio channels. (1 for mono, 2 for stereo, ...) */
};

/** Type for usec specifications (unsigned). May be either 32 or 64 bit, depending on the architecture */
typedef uint64_t pa_usec_t;

/** Return the amount of bytes playback of a second of audio with the specified sample type takes */
size_t pa_bytes_per_second(const struct pa_sample_spec *spec);

/** Return the size of a frame with the specific sample type */
size_t pa_frame_size(const struct pa_sample_spec *spec);

/** Calculate the time the specified bytes take to play with the specified sample type */
pa_usec_t pa_bytes_to_usec(uint64_t length, const struct pa_sample_spec *spec);

/** Return non-zero when the sample type specification is valid */
int pa_sample_spec_valid(const struct pa_sample_spec *spec);

/** Return non-zero when the two sample type specifications match */
int pa_sample_spec_equal(const struct pa_sample_spec*a, const struct pa_sample_spec*b);

/** Maximum required string length for pa_sample_spec_snprint() */
#define PA_SAMPLE_SPEC_SNPRINT_MAX 32

/** Pretty print a sample type specification to a string */
void pa_sample_spec_snprint(char *s, size_t l, const struct pa_sample_spec *spec);

/** Volume specification: 0: silence; < 256: diminished volume; 256: normal volume; > 256 amplified volume */
typedef uint32_t pa_volume_t;

/** Normal volume (100%) */
#define PA_VOLUME_NORM (0x100)

/** Muted volume (0%) */
#define PA_VOLUME_MUTED (0)

/** Multiply two volumes specifications, return the result. This uses PA_VOLUME_NORM as neutral element of multiplication. */
pa_volume_t pa_volume_multiply(pa_volume_t a, pa_volume_t b);

/** Convert volume from decibel to linear level. \since 0.4 */
pa_volume_t pa_volume_from_dB(double f);

/** Convert volume from linear level to decibel.  \since 0.4 */
double pa_volume_to_dB(pa_volume_t v);

/** Convert volume to scaled value understandable by the user (between 0 and 1). \since 0.6 */
double pa_volume_to_user(pa_volume_t v);

/** Convert user volume to polypaudio volume. \since 0.6 */
pa_volume_t pa_volume_from_user(double v);

#ifdef INFINITY
#define PA_DECIBEL_MININFTY (-INFINITY)
#else
/** This value is used as minus infinity when using pa_volume_{to,from}_dB(). \since 0.4 */
#define PA_DECIBEL_MININFTY (-200)
#endif

/** Pretty print a byte size value. (i.e. "2.5 MB") */
void pa_bytes_snprint(char *s, size_t l, unsigned v);

/** Parse a sample format text */
enum pa_sample_format pa_parse_sample_format(const char *format);

PA_C_DECL_END

#endif