xref: /netbsd-src/sys/dev/audio/audiofil.h (revision e622eac459adf11c2e710d7a4de0f05510bbbe61)
1 /*	$NetBSD: audiofil.h,v 1.2 2019/05/08 13:40:17 isaki Exp $	*/
2 
3 /*
4  * Copyright (C) 2017 Tetsuya Isaki. All rights reserved.
5  * Copyright (C) 2017 Y.Sugahara (moveccr). All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #ifndef _SYS_DEV_AUDIO_AUDIOFIL_H_
30 #define _SYS_DEV_AUDIO_AUDIOFIL_H_
31 
32 /*
33  * Number of bits for internal format.
34  * XXX 32bit mode is not completed.
35  * XXX Is this necessary?
36  */
37 #define AUDIO_INTERNAL_BITS		16
38 /*#define AUDIO_INTERNAL_BITS		32 */
39 
40 #if AUDIO_INTERNAL_BITS == 16
41 
42 typedef int16_t  aint_t;	/* audio          integer */
43 typedef uint16_t auint_t;	/* audio unsigned integer */
44 typedef int32_t  aint2_t;	/* audio          wide integer */
45 typedef uint32_t auint2_t;	/* audio unsigned wide integer */
46 #define AINT_T_MAX	((aint_t)0x7fff)
47 #define AINT_T_MIN	((aint_t)0x8000)
48 
49 #elif AUDIO_INTERNAL_BITS == 32
50 
51 typedef int32_t  aint_t;
52 typedef uint32_t auint_t;
53 typedef int64_t  aint2_t;
54 typedef uint64_t auint2_t;
55 #define AINT_T_MAX	((aint_t)0x7fffffff)
56 #define AINT_T_MIN	((aint_t)0x80000000)
57 
58 #else
59 #error Invalid AUDIO_INTERNAL_BITS
60 #endif
61 
62 /*
63  * audio format.
64  *
65  * precision <= stride always holds.
66  */
67 typedef struct {
68 	u_int	sample_rate;	/* sample rate in Hz */
69 	u_int	encoding;	/* AUDIO_ENCODING_* */
70 	u_int	stride;		/* container bits of a sample */
71 	u_int	precision;	/* valid bits of a sample */
72 	u_int	channels;	/* 1..AUDIO_MAX_CHANNELS */
73 } audio_format2_t;
74 
75 /* Parameters for conversion filters */
76 typedef struct {
77 	/* Pointer to source samples. */
78 	const void *src;
79 	/* Input format */
80 	const audio_format2_t *srcfmt;
81 
82 	/* Pointer to destination buffer. */
83 	void *dst;
84 	/* Output format */
85 	const audio_format2_t *dstfmt;
86 
87 	/*
88 	 * Number of frames to be converted.
89 	 * The conversion filter must output 'count' frames.  src and dst
90 	 * are guaranteed that at least 'count' frames are contiguous.
91 	 * The caller does not reference this count after calling, so
92 	 * that the conversion filter can use passed this variable.
93 	 * For example, decrementing it directly.
94 	 */
95 	u_int count;
96 
97 	/* The conversion filters can use this pointer. */
98 	void *context;
99 } audio_filter_arg_t;
100 
101 typedef void(*audio_filter_t)(audio_filter_arg_t *arg);
102 
103 /* Filter registration structure */
104 typedef struct {
105 	audio_filter_t codec;	/* conversion function */
106 	void *context;		/* optional codec's argument */
107 } audio_filter_reg_t;
108 
109 #endif /* !_SYS_DEV_AUDIO_AUDIOFIL_H_ */
110