Vorbis comment
Vorbis comment is a metadata container of Xiph.Org Foundation to store printed text. This allows, for example, metadata may be added to the music files, containing the information about the particular piece of music. It is used in Xiphs free codecs Vorbis, FLAC and Speex, comparable to ID3 tags for MP3 files.
How APEv2 offers Vorbis comment unlike ID3 the ability to even create fields to store the information.
Format
A Vorbis tag consists of a list of fields in the format field name = data. The field name can consist of printable ASCII characters as well as the 0x20 (space) to 0x7D ( '}' ), except 0x3D ( '=' ) and 0x7E ( ' ~ '). The system does not distinguish between upper and lower case, title and TITLE therefore refer to the same field. The number of fields and their lengths are limited to 4,294,967,295 (the largest value of a 32 -bit integer), but most editing programs have stricter limits.
The data is encoded in UTF -8, whereby any Unicode strings can be used as values.
There are any field name allowed and the format of the values is not mandatory. Also, field names may be awarded more than once, which is recommended to have multiple values for a field name - for example, in a work in which several artists were involved. Thus, the system is in contrast to ID3, which imposes extensive regulations.
The specification defines several example field name as title (title), artist ( artist), album and track number ( song number), along with most applications provide de facto standards such as disc number ( CD # ) and fields for Replay Gain information.
Storing binary data in Vorbis comment is not provided. Of the metadata container was designed to be part of a respective container format. It is intended to store additional binary data directly in these respective containers.
The fields and their meanings
Chapter brands
The chapter markers can also be easily added as a Vorbis comment fields.
CHAPTER001 = 00:00:00.000
CHAPTER001NAME = First Chapter
CHAPTER002 = 00:05:00.000
CHAPTER002NAME = The second chapter is more beautiful
For more information about the chapter marks see Xiph.Org ' s Vorbis Comment Chapter Extension ( English).