The past
Once upon a time, there were some giant companies that, with the failure of
the 4-channel battle fresh in mind, formed an expert group with the mission to
invent tomorrow's technology in sound compression. Fortunately, they did. The
format, named MPEG Layer 3 or for short MP3, took advantage of the fact that our
ears are not nearly as good as we generally believe them to be, and thus
omitting frequencies that we wouldn't hear anyway. They also made the format
suitable for streaming by letting the sound be represented in small,
individually compressed blocks of audio data. Each block had a header containing
some information relevant to the decoding process. As they ended up with a few
bits to much, they used them for some additional information such as a 'copyright'
bit and a 'private' bit.
Since the format had such an outstanding compression and still very good
sound quality, it was soon adapted as the de facto standard for digital music.
The lack of possibilities to include textual information in the files was
however disturbingly present. Suddenly, someone (Eric Kemp alias NamkraD, I've
been told) had a vision of a fix-sized 128-byte tag that would reside at the end
of the audio file. It would include title, artist, album, year, genre and a
comment field. Someone, possibly the very same someone, implemented this and
everyone was happy. Soon afterwards, Michael Mutschler, the author of MP3ext,
extended this tag, called ID3, to also include which track on the CD the music
originated from. He used the last two bytes of the comment field for this and
named his variant ID3 v1.1. (more information about ID3 and ID3v1.1 can be found
here).
The present
The ID3 v1.1 tag still had some obvious limitations and drawbacks, though. It
supported only a few fields of information, and those were limited to 30
characters, making it impossible to correctly describe "The Hitchhiker's Guide
to the Galaxy from BBC Radio" as well as "P.I. Tchaikovsky's Nutcracker Suite Op.
71 a, Ouverture miniature danses caractéristiques by The New Philharmonic
Orchestra, London, conducted by Laurence Siegel". Since the position of the ID3
v1.1 tag is at the end of the audio file it will also be the last thing to
arrive when the file is being streamed. The fix size of 128 bytes also makes it
impossible to extend further. That's why I (Martin Nilsson) and several along
with me thought that a new ID3 tag would be appropriate.
The new ID3 tag is named ID3v2 and is currently in a state of 'informal
standard'. That is, we decided, since there were less and less improvements and
additions made, to proclaim the draft as a standard (an informal one since no
standardization body has approved this decision). You can find the informal
standard here. ID3v2 is often followed by its revision number, i.e. the current
informal standard is ID3v2.4.0.
Original text by Martin Nilsson
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