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id3v2.h
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1 /*
2  * ID3v2 header parser
3  * Copyright (c) 2003 Fabrice Bellard
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #ifndef AVFORMAT_ID3V2_H
23 #define AVFORMAT_ID3V2_H
24 
25 #include <stdint.h>
26 #include "avformat.h"
27 #include "internal.h"
28 #include "metadata.h"
29 
30 #define ID3v2_HEADER_SIZE 10
31 
32 /**
33  * Default magic bytes for ID3v2 header: "ID3"
34  */
35 #define ID3v2_DEFAULT_MAGIC "ID3"
36 
37 #define ID3v2_FLAG_DATALEN 0x0001
38 #define ID3v2_FLAG_UNSYNCH 0x0002
39 #define ID3v2_FLAG_ENCRYPTION 0x0004
40 #define ID3v2_FLAG_COMPRESSION 0x0008
41 
47 };
48 
49 typedef struct ID3v2EncContext {
50  int version; ///< ID3v2 minor version, either 3 or 4
51  int64_t size_pos; ///< offset of the tag total size
52  int len; ///< size of the tag written so far
54 
55 typedef struct ID3v2ExtraMeta {
56  const char *tag;
57  void *data;
60 
61 typedef struct ID3v2ExtraMetaGEOB {
62  uint32_t datasize;
68 
69 typedef struct ID3v2ExtraMetaAPIC {
71  const char *type;
73  enum AVCodecID id;
75 
76 typedef struct ID3v2ExtraMetaPRIV {
79  uint32_t datasize;
81 
82 /**
83  * Detect ID3v2 Header.
84  * @param buf must be ID3v2_HEADER_SIZE byte long
85  * @param magic magic bytes to identify the header.
86  * If in doubt, use ID3v2_DEFAULT_MAGIC.
87  */
88 int ff_id3v2_match(const uint8_t *buf, const char *magic);
89 
90 /**
91  * Get the length of an ID3v2 tag.
92  * @param buf must be ID3v2_HEADER_SIZE bytes long and point to the start of an
93  * already detected ID3v2 tag
94  */
95 int ff_id3v2_tag_len(const uint8_t *buf);
96 
97 /**
98  * Read an ID3v2 tag into specified dictionary and retrieve supported extra metadata.
99  *
100  * Chapters are not currently read by this variant.
101  *
102  * @param metadata Parsed metadata is stored here
103  * @param extra_meta If not NULL, extra metadata is parsed into a list of
104  * ID3v2ExtraMeta structs and *extra_meta points to the head of the list
105  */
106 void ff_id3v2_read_dict(AVIOContext *pb, AVDictionary **metadata, const char *magic, ID3v2ExtraMeta **extra_meta);
107 
108 /**
109  * Read an ID3v2 tag, including supported extra metadata and chapters.
110  *
111  * Data is read from and stored to AVFormatContext.
112  *
113  * @param extra_meta If not NULL, extra metadata is parsed into a list of
114  * ID3v2ExtraMeta structs and *extra_meta points to the head of the list
115  * @param[opt] max_search_search restrict ID3 magic number search (bytes from start)
116  */
117 void ff_id3v2_read(AVFormatContext *s, const char *magic, ID3v2ExtraMeta **extra_meta,
118  unsigned int max_search_size);
119 
120 /**
121  * Initialize an ID3v2 tag.
122  */
123 void ff_id3v2_start(ID3v2EncContext *id3, AVIOContext *pb, int id3v2_version,
124  const char *magic);
125 
126 /**
127  * Convert and write all global metadata from s into an ID3v2 tag.
128  */
130 
131 /**
132  * Write an attached picture from pkt into an ID3v2 tag.
133  */
135 
136 /**
137  * Finalize an opened ID3v2 tag.
138  */
139 void ff_id3v2_finish(ID3v2EncContext *id3, AVIOContext *pb, int padding_bytes);
140 
141 /**
142  * Write an ID3v2 tag containing all global metadata from s.
143  * @param id3v2_version Subversion of ID3v2; supported values are 3 and 4
144  * @param magic magic bytes to identify the header
145  * If in doubt, use ID3v2_DEFAULT_MAGIC.
146  */
147 int ff_id3v2_write_simple(struct AVFormatContext *s, int id3v2_version, const char *magic);
148 
149 /**
150  * Free memory allocated parsing special (non-text) metadata.
151  * @param extra_meta Pointer to a pointer to the head of a ID3v2ExtraMeta list, *extra_meta is set to NULL.
152  */
153 void ff_id3v2_free_extra_meta(ID3v2ExtraMeta **extra_meta);
154 
155 /**
156  * Create a stream for each APIC (attached picture) extracted from the
157  * ID3v2 header.
158  */
160 
163 
164 /**
165  * A list of text information frames allowed in both ID3 v2.3 and v2.4
166  * http://www.id3.org/id3v2.4.0-frames
167  * http://www.id3.org/id3v2.4.0-changes
168  */
169 extern const char ff_id3v2_tags[][4];
170 
171 /**
172  * ID3v2.4-only text information frames.
173  */
174 extern const char ff_id3v2_4_tags[][4];
175 
176 /**
177  * ID3v2.3-only text information frames.
178  */
179 extern const char ff_id3v2_3_tags[][4];
180 
181 extern const CodecMime ff_id3v2_mime_tags[];
182 
183 extern const char *ff_id3v2_picture_types[21];
184 
185 #endif /* AVFORMAT_ID3V2_H */