FFmpeg/libavformat/id3v2.h
Richard Shaffer 8a4cc0a256 avformat: add option to parse/store ID3 PRIV tags in metadata.
Enables getting access to ID3 PRIV tags from the command-line or metadata API
when demuxing. The PRIV owner is stored as the metadata key prepended with
"id3v2_priv.", and the data is stored as the metadata value. As PRIV tags may
contain arbitrary data, non-printable characters, including NULL bytes, are
escaped as \xXX.

Similarly, any metadata tags that begin with "id3v2_priv." are inserted as ID3
PRIV tags into the output (assuming the format supports ID3). \xXX sequences in
the value are un-escaped to their byte value.

Signed-off-by: wm4 <nfxjfg@googlemail.com>
2018-01-24 04:01:01 +01:00

210 lines
6.1 KiB
C

/*
* ID3v2 header parser
* Copyright (c) 2003 Fabrice Bellard
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef AVFORMAT_ID3V2_H
#define AVFORMAT_ID3V2_H
#include <stdint.h>
#include "avformat.h"
#include "internal.h"
#include "metadata.h"
#define ID3v2_HEADER_SIZE 10
/**
* Default magic bytes for ID3v2 header: "ID3"
*/
#define ID3v2_DEFAULT_MAGIC "ID3"
#define ID3v2_FLAG_DATALEN 0x0001
#define ID3v2_FLAG_UNSYNCH 0x0002
#define ID3v2_FLAG_ENCRYPTION 0x0004
#define ID3v2_FLAG_COMPRESSION 0x0008
#define ID3v2_PRIV_METADATA_PREFIX "id3v2_priv."
enum ID3v2Encoding {
ID3v2_ENCODING_ISO8859 = 0,
ID3v2_ENCODING_UTF16BOM = 1,
ID3v2_ENCODING_UTF16BE = 2,
ID3v2_ENCODING_UTF8 = 3,
};
typedef struct ID3v2EncContext {
int version; ///< ID3v2 minor version, either 3 or 4
int64_t size_pos; ///< offset of the tag total size
int len; ///< size of the tag written so far
} ID3v2EncContext;
typedef struct ID3v2ExtraMeta {
const char *tag;
void *data;
struct ID3v2ExtraMeta *next;
} ID3v2ExtraMeta;
typedef struct ID3v2ExtraMetaGEOB {
uint32_t datasize;
uint8_t *mime_type;
uint8_t *file_name;
uint8_t *description;
uint8_t *data;
} ID3v2ExtraMetaGEOB;
typedef struct ID3v2ExtraMetaAPIC {
AVBufferRef *buf;
const char *type;
uint8_t *description;
enum AVCodecID id;
} ID3v2ExtraMetaAPIC;
typedef struct ID3v2ExtraMetaPRIV {
uint8_t *owner;
uint8_t *data;
uint32_t datasize;
} ID3v2ExtraMetaPRIV;
typedef struct ID3v2ExtraMetaCHAP {
uint8_t *element_id;
uint32_t start, end;
AVDictionary *meta;
} ID3v2ExtraMetaCHAP;
/**
* Detect ID3v2 Header.
* @param buf must be ID3v2_HEADER_SIZE byte long
* @param magic magic bytes to identify the header.
* If in doubt, use ID3v2_DEFAULT_MAGIC.
*/
int ff_id3v2_match(const uint8_t *buf, const char *magic);
/**
* Get the length of an ID3v2 tag.
* @param buf must be ID3v2_HEADER_SIZE bytes long and point to the start of an
* already detected ID3v2 tag
*/
int ff_id3v2_tag_len(const uint8_t *buf);
/**
* Read an ID3v2 tag into specified dictionary and retrieve supported extra metadata.
*
* @param metadata Parsed metadata is stored here
* @param extra_meta If not NULL, extra metadata is parsed into a list of
* ID3v2ExtraMeta structs and *extra_meta points to the head of the list
*/
void ff_id3v2_read_dict(AVIOContext *pb, AVDictionary **metadata, const char *magic, ID3v2ExtraMeta **extra_meta);
/**
* Read an ID3v2 tag, including supported extra metadata.
*
* Data is read from and stored to AVFormatContext.
*
* @param extra_meta If not NULL, extra metadata is parsed into a list of
* ID3v2ExtraMeta structs and *extra_meta points to the head of the list
* @param[opt] max_search_search restrict ID3 magic number search (bytes from start)
*/
void ff_id3v2_read(AVFormatContext *s, const char *magic, ID3v2ExtraMeta **extra_meta,
unsigned int max_search_size);
/**
* Initialize an ID3v2 tag.
*/
void ff_id3v2_start(ID3v2EncContext *id3, AVIOContext *pb, int id3v2_version,
const char *magic);
/**
* Convert and write all global metadata from s into an ID3v2 tag.
*/
int ff_id3v2_write_metadata(AVFormatContext *s, ID3v2EncContext *id3);
/**
* Write an attached picture from pkt into an ID3v2 tag.
*/
int ff_id3v2_write_apic(AVFormatContext *s, ID3v2EncContext *id3, AVPacket *pkt);
/**
* Finalize an opened ID3v2 tag.
*/
void ff_id3v2_finish(ID3v2EncContext *id3, AVIOContext *pb, int padding_bytes);
/**
* Write an ID3v2 tag containing all global metadata from s.
* @param id3v2_version Subversion of ID3v2; supported values are 3 and 4
* @param magic magic bytes to identify the header
* If in doubt, use ID3v2_DEFAULT_MAGIC.
*/
int ff_id3v2_write_simple(struct AVFormatContext *s, int id3v2_version, const char *magic);
/**
* Free memory allocated parsing special (non-text) metadata.
* @param extra_meta Pointer to a pointer to the head of a ID3v2ExtraMeta list, *extra_meta is set to NULL.
*/
void ff_id3v2_free_extra_meta(ID3v2ExtraMeta **extra_meta);
/**
* Create a stream for each APIC (attached picture) extracted from the
* ID3v2 header.
*/
int ff_id3v2_parse_apic(AVFormatContext *s, ID3v2ExtraMeta **extra_meta);
/**
* Create chapters for all CHAP tags found in the ID3v2 header.
*/
int ff_id3v2_parse_chapters(AVFormatContext *s, ID3v2ExtraMeta **extra_meta);
/**
* Parse PRIV tags into a dictionary. The PRIV owner is the metadata key. The
* PRIV data is the value, with non-printable characters escaped.
*/
int ff_id3v2_parse_priv_dict(AVDictionary **d, ID3v2ExtraMeta **extra_meta);
/**
* Add metadata for all PRIV tags in the ID3v2 header. The PRIV owner is the
* metadata key. The PRIV data is the value, with non-printable characters
* escaped.
*/
int ff_id3v2_parse_priv(AVFormatContext *s, ID3v2ExtraMeta **extra_meta);
extern const AVMetadataConv ff_id3v2_34_metadata_conv[];
extern const AVMetadataConv ff_id3v2_4_metadata_conv[];
/**
* A list of text information frames allowed in both ID3 v2.3 and v2.4
* http://www.id3.org/id3v2.4.0-frames
* http://www.id3.org/id3v2.4.0-changes
*/
extern const char ff_id3v2_tags[][4];
/**
* ID3v2.4-only text information frames.
*/
extern const char ff_id3v2_4_tags[][4];
/**
* ID3v2.3-only text information frames.
*/
extern const char ff_id3v2_3_tags[][4];
extern const CodecMime ff_id3v2_mime_tags[];
extern const char * const ff_id3v2_picture_types[21];
#endif /* AVFORMAT_ID3V2_H */