Rename struct audio_format_info to afh_info.
[paraslash.git] / afh.h
1 /*
2 * Copyright (C) 2005-2007 Andre Noll <maan@systemlinux.org>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7 /** \file afh.h structures for audio format handling (para_server) */
8
9 /** \cond */
10 #ifdef HAVE_OGGVORBIS
11 #define OV_AUDIO_FORMAT " ogg"
12 #else
13 #define OV_AUDIO_FORMAT ""
14 #endif
15
16 #ifdef HAVE_FAAD
17 #define AAC_AUDIO_FORMAT " aac"
18 #else
19 #define AAC_AUDIO_FORMAT ""
20 #endif
21
22 #define SUPPORTED_AUDIO_FORMATS "mp3" OV_AUDIO_FORMAT AAC_AUDIO_FORMAT
23
24 /** \endcond */
25
26 /** size of the audio_file info string */
27 #define AUDIO_FILE_INFO_SIZE 256
28
29 /**
30 * Audio format dependent information. Details vary between each audio format
31 * handler.
32 */
33 struct afh_info {
34 /** The number of chunks this audio file contains. */
35 long unsigned chunks_total;
36 /** The length of the audio file in seconds. */
37 long unsigned seconds_total;
38 /** A string that gets filled in by the audio format handler. */
39 char info_string[AUDIO_FILE_INFO_SIZE];
40 /**
41 * The table that specifies the offset of the individual pieces in
42 * the current audio file.
43 */
44 uint32_t *chunk_table;
45 /** Period of time between sending data chunks. */
46 struct timeval chunk_tv;
47 /** End of file timeout - Do not load new audio file until this time. */
48 struct timeval eof_tv;
49 /**
50 * The header is needed by senders in case a new client connects in the
51 * middle of the stream. The length of the header defaults to zero
52 * which means that this audio format does not need any special header
53 * treatment. The audio format handler does not need to set this to
54 * zero in this case.
55 */
56 unsigned header_len;
57 /**
58 * The position of the header within the audio file. Ignored if \a
59 * header_len equals zero.
60 */
61 unsigned header_offset;
62 /** The number of channels. */
63 uint8_t channels;
64 /** Frquency on Hz. */
65 uint16_t frequency;
66 /** Exact meaning depends on audio format. */
67 uint16_t bitrate;
68 };
69
70 /**
71 * Structure for audio format handling.
72 *
73 * There's one such struct for each supported audio format. Initially, only \a
74 * name and \a init are defined. During the startup process, para_server calls
75 * the \a init function of each audio format handler which is expected to fill
76 * in the other part of this struct.
77 */
78 struct audio_format_handler {
79 /** Name of the audio format. */
80 const char *name;
81 /**
82 * Pointer to the audio format handler's init function.
83 *
84 * Must initialize all function pointers and is assumed to succeed.
85 */
86 void (*init)(struct audio_format_handler*);
87 /** Typical file endings for files that can be handled by this afh. */
88 const char **suffixes;
89 /**
90 * Check if this audio format handler can handle the file.
91 *
92 * This is a pointer to a function returning whether a given file is
93 * valid for this audio format. A negative return value indicates that
94 * this audio format handler is unable to decode the given file. On
95 * success, the function must return a positive value and fill in the
96 * given struct afh_info.
97 *
98 * \sa struct afh_info
99 */
100 int (*get_file_info)(char *map, size_t numbytes,
101 struct afh_info *afi);
102 };
103
104 void afh_init(void);
105 int guess_audio_format(const char *name);
106 int compute_afhi(const char *path, char *data, size_t size,
107 struct afh_info *afhi);
108 const char *audio_format_name(int);