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
|
/* $OpenBSD: aparams.h,v 1.2 2008/10/26 08:49:43 ratchov Exp $ */
/*
* Copyright (c) 2008 Alexandre Ratchov <alex@caoua.org>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#ifndef APARAMS_H
#define APARAMS_H
#include <sys/param.h>
#define NCHAN_MAX 16 /* max channel in a stream */
#define RATE_MIN 4000 /* min sample rate */
#define RATE_MAX 192000 /* max sample rate */
#define BITS_MIN 1 /* min bits per sample */
#define BITS_MAX 32 /* max bits per sample */
/*
* maximum size of the encording string (the longest possible
* encoding is ``s24le3msb'')
*/
#define ENCMAX 10
#if BYTE_ORDER == LITTLE_ENDIAN
#define NATIVE_LE 1
#elif BYTE_ORDER == BIG_ENDIAN
#define NATIVE_LE 0
#else
/* not defined */
#endif
/*
* default bytes per sample for the given bits per sample
*/
#define APARAMS_BPS(bits) (((bits) <= 8) ? 1 : (((bits) <= 16) ? 2 : 4))
/*
* encoding specification
*/
struct aparams {
unsigned bps; /* bytes per sample */
unsigned bits; /* actually used bits */
unsigned le; /* 1 if little endian, 0 if big endian */
unsigned sig; /* 1 if signed, 0 if unsigned */
unsigned msb; /* 1 if msb justified, 0 if lsb justified */
unsigned cmin, cmax; /* provided/consumed channels */
unsigned rate; /* frames per second */
};
/*
* Samples are numbers in the interval [-1, 1[, note that 1, the upper
* boundary is excluded. We represent them in 16-bit signed fixed point
* numbers, so that we can do all multiplications and divisions in
* 32-bit precision without having to deal with overflows.
*/
#define ADATA_SHIFT (8 * sizeof(short) - 1)
#define ADATA_UNIT (1 << ADATA_SHIFT)
#define ADATA_MAX (ADATA_UNIT - 1)
#define ADATA_MUL(x,y) (((x) * (y)) >> ADATA_SHIFT)
void aparams_init(struct aparams *, unsigned, unsigned, unsigned);
void aparams_print(struct aparams *);
void aparams_print2(struct aparams *, struct aparams *);
int aparams_eq(struct aparams *, struct aparams *);
unsigned aparams_bpf(struct aparams *);
int aparams_strtoenc(struct aparams *, char *);
int aparams_enctostr(struct aparams *, char *);
void aparams_copyenc(struct aparams *, struct aparams *);
#endif /* !defined(APARAMS_H) */
|