What is Ogg Vorbis?
Ogg Vorbis is a new audio compression format. It is roughly
comparable to other formats used to store and play digital
music, such as MP3, VQF, AAC, and other digital audio formats.
It is different from these other formats because it is
completely free, open, and unpatented.
What do all the names mean?
Vorbis is the name for the specific audio compression scheme
used to create Ogg Vorbis files. It is part of the Ogg project,
which is a blanket project designed to create a fully open
multimedia system. Right now, Ogg Vorbis is the only functional
part of the Ogg project which is anywhere near completion.
Where do the names come from? What does the logo mean?
Xiph.org has a page explaining the sources and meanings of the
names and logos.
What is the file extension for Ogg Vorbis?
Since it is part of the Ogg project, Vorbis files have the
Does Vorbis completely replace MP3, or is it just a
Ogg Vorbis has been designed to completely replace all
proprietary, patented audio formats. That means that you can
encode all your music or audio content in Vorbis and never look
When will Ogg Vorbis be done?
There are stable reference implementations available now,
and the file format has been finished for some time. A Vorbis
file created today will still be compatible with future decoders
for years to come. The format has been designed to be flexible,
so that the developers can continue to improve file size and
sound quality without "breaking" older encoders and players.
I'm an artist. Why should I be interested?
There are a couple of reasons:
Although not all artists realize it, MP3 is what is known as a "lossy"
format. Thus, much of the sound data is removed when MP3 files
are created. This results in a file with inferior sound quality
to a CD. Vorbis is also a "lossy" format, but uses superior
acoustic models to reduce the damage. Thus, music released in
Vorbis will sound better than a comparably sized MP3 file.
Also, artists should be concerned about licensing terms for
formats. If you decide to sell your music in MP3 format, you are
responsible for paying Fraunhofer a percentage of each sale
because you are using their patents. Vorbis is patent and
license-free, so you will never need to pay anyone in order to
sell, give away, or stream your own music.
I'm a music fan. Why should I be interested?
For one, Vorbis provides a high-quality format for you to listen
to your music. For a given file size, Vorbis sounds better than
MP3, and is getting better as development continues. Vorbis
already enjoys widespread player support and should be
compatible with several major hardware players soon. With Vorbis,
you can listen to your music with higher quality in less space.
Also, using Vorbis means your player and encoder choices aren't
bound by licensing terms. Right now, you can only choose from a
few encoders to create your MP3 files, because most companies
won't or can't pay the licensing terms for encoders. Using
Vorbis lets you choose from a wide variety of encoders.
I'm a developer. Why should I be interested?
If you develop hardware or software audio players, you cannot
distribute your work without being affected by proprietary audio
patent licensing terms. With Vorbis, you can create hardware or
software products to encode or decode music files without
restrictions, royalty payments, or limits on distribution.
Vorbis also provides a flexible, high-quality format that is of
great interest to all the audio geeks out there. For more
developer information, please refer to our developer site.
I run a music company. Why should I be interested?
Music companies should be very interested in the Ogg Vorbis
format. Other technologies require large financial investments
to get started, but Vorbis offers a unique platform that is
easily reachable for growing companies and a money saver for
established businesses. Because of its wide player support and
its open nature, your customers and clients will not be plagued
by incompatibilities and they will appreciate the higher sound
quality as well.
What licensing applies to the Ogg Vorbis format?
The Ogg Vorbis specification is in the public
domain. It is completely free for commercial or noncommercial
use. That means that commercial developers may independently
write Ogg Vorbis software which is compatible with the
specification for no charge and without restrictions of any
kind. However, developers that wish to use the open source
software we have written must adhere to certain rules.
What licensing applies to the included Ogg Vorbis software?
The bundled Ogg Vorbis utility software is released under the
terms of the GNU GPL, or GNU General Public License. The details
can be found at www.gnu.org.
The libraries and SDKs are released under the more
business-friendly BSD license. Please note that developers are
still free to use the specification to independently write
closed-source implementations of Ogg Vorbis which are not bound
by these licenses.
We make commercial, closed source software. Can I use Ogg
Vorbis at all? What licensing do I need to pay?
Again, there are no licensing fees for ANY use of the Ogg Vorbis
specification. As a commercial developer, you are free to create
and sell (or give away) open or closed source implementations of
Vorbis encoders, decoders, or other tools. However, if you use
our software rather than writing an independent implementation,
you must respect the terms of the license. Our libraries
(available under the BSD license) can be used whole or in part
by closed source applications.
Are there licensing fees for distributing, selling, or
streaming media in the Ogg Vorbis format like there are in other
formats, such as MP3?
I've heard that Vorbis is a "lossy" codec. What does this
There are two broad classes of compression algorithms:
lossless and lossy. Lossless compression algorithms produce
compressed data that can be decoded to output that is identical
to the original. Zip is a very common example of a lossless
compression format. FLAC is a lossless compression format that
is specifically designed for audio.
The other type of compression algorithm is called lossy. This
form of compression is very popular with multimedia data, like
pictures, movies, and sound. Since these types of information
are perceived by humans with imperfect senses, the original data
does not have to be reproduced exactly. Some of the information
in the original file can actually be discarded because we
wouldn't notice it even if it was there. Lossy codecs can
achieve much higher compression than lossless codecs by
intelligently discarding unneeded information. In most cases,
some loss of quality can be tolerated, so even more data can be
discarded, further increasing compression. MP3, RealAudio, and
Vorbis all use lossy audio compression. This means that a Vorbis
file, for example, will decode to a WAV file that is different
than the original. The differences may or may not be noticable,
depending upon the quality selected during compression.
Will Ogg Vorbis audio quality improve?
Yes. Vorbis has a flexible format which allows significant
tuning of sound quality and training of the algorithms even
after the file format is frozen. Vorbis sounds very good today,
and will continue to sound better every day.
Why is Ogg Vorbis better than the other "New MP3" codecs that
Vorbis sounds better. Vorbis is open, so you're free to use it
on your favorite platform. Vorbis doesn't have intellectual
property restrictions to get in the way. And Vorbis doesn't just
try to sound better, it tries to do things fundamentally better
in all the ways that it can.
Can I convert my MP3 collection to the Ogg Vorbis format?
You can convert any audio format to Ogg Vorbis. However,
converting from one lossy format, like MP3, to another lossy
format, like Vorbis, is generally a bad idea. Both MP3 and
Vorbis encoders achieve high compression ratios by throwing away
parts of the audio waveform that you probably won't hear.
However, the MP3 and Vorbis codecs are very different, so they
each will throw away different parts of the audio, although
there certainly is some overlap. Converting a MP3 to Vorbis
involves decoding the MP3 file back to an uncompressed format,
like WAV, and recompressing it using the Ogg Vorbis encoder. The
decoded MP3 will be missing the parts of the original audio that
the MP3 encoder chose to discard. The Ogg Vorbis encoder will
then discard other audio components when it compresses the data.
At best, the result will be an Ogg file that sounds the same as
your original MP3, but it is most likely that the resulting file
will sound worse than your original MP3. In no case will you get
a file that sounds better than the original MP3.
Since many music players can play both MP3 and Ogg files, there
is no reason that you should have to switch all of your files to
one format or the other. If you like Ogg Vorbis, then we would
encourage you to use it when you encode from original, lossless
audio sources (like CDs). When encoding from originals, you will
find that you can make Ogg files that are both smaller and
better quality than MP3.
(If you must absolutely must convert from MP3 to Ogg, there are
several conversion scripts available on Freshmeat.)
What does the "Quality" setting mean?
Beginning with libvorbis 1.0rc3, audio quality is no longer
measured in kilobits per second, but on an arbitrary scale of 0
to 10, called "quality." This change in terminology was brought
about by a tuning of the variable-bitrate algorithm that
produces better sound quality for a given average bitrate, but
which does not adhere as strictly to that average as a target.
This new scale of measurement is not tied to a quantifiable
characteristic of the stream, like bitrate, so it's a fairly
subjective metric, but provides a more stable basis of
comparison to other codecs and is relatively future-proof. As
Segher Boessenkool <email@example.com> explained, "if you upgrade
to a new vorbis encoder, and you keep the same quality setting,
you will get smaller files which sound the same. If you keep the
same nominal bitrate, you get about the same size files, which
sound somewhat better." The former behavior is the aim of the
quality metric, so encoding to a target bitrate is now
officially deprecated for all uses except streaming over
For now, quality 0 is roughly equivalent to 64kbps average, 5 is
roughly 160kbps, and 10 gives about 400kbps. Most people seeking
very-near-CD-quality audio encode at a quality of 5 or, for
lossless stereo coupling, 6. The default setting is quality 3,
which at approximately 110kbps gives a smaller filesize and
significantly better fidelity than .mp3 compression at 128kbps.
How does Vorbis fare for speech compression?
It works well, but is generally not the optimal solution.
Vorbis is designed for the compression of music and general
purpose audio. Special purpose codecs can achieve much greater
compression of speech than Vorbis. Vorbis also tends to have a
latency that is too high for telephony, a common use of speech
codecs. Read the Speech Coding and Compression FAQ for more
details. Those looking for an open-source, patent-free speech
codec should take a look at Speex.
How big are Ogg Vorbis files? How do they compare to MP3
files at similar bitrates?
Two files encoded at the same bitrate, will always be the
same size, if they are both encoded with CBR (Constant Bitrate).
The current Vorbis encoder can encode files in VBR (Variable
Bitrate) which can produce smaller files with better quality,
since it doesn't have to waste data for audio that is easy to
encode. Files produced by the Vorbis encoder at the default
quality will be similar in size to 110kbps MP3 files, but will
What is the maximum bitrate at which Vorbis can be encoded?
Theoretically, there isn't one. Vorbis is tuned for bitrates
of 16kbps to 128kbps PER CHANNEL. But there's nothing in the
spec that says you can't encode a file at 512kbps or 8kbps. The
current encoder supports the following bitrates: 64-500kbps
stereo and 32-256kbps mono (at 44.1kHz sampling rate). Lower
bitrates will be officially available in future versions.
Does Ogg Vorbis have the capability to show song titles and
artist information when the file is played or streamed?
Yes, Vorbis includes a flexible, complete comment field for song
and artist info, as well as other track data. The official
encoder, oggenc, allows you to enter comment info at
encode-time. Other 3rd-party encoding tools also let you enter
or edit track data.
How fast are the encoders/decoders?
Right now the encoder is about as fast as most commercial audio
encoders (and about twice as fast as beta 3), but not nearly as
fast as some others. Since we are using unoptimized beta code,
this is to be expected. As the vorbis tools mature they will
become faster. The decoding is roughly the same complexity as
MP3 decoding, and once the Vorbis decoding tools are optimized,
they should decode at similar speeds. Decoding speed has
increased 3-4x over the first beta already, after the first
stage of optimization.
If you're interested in our progress on a video codec, check out
Theora at http://www.theora.org. Theora's 1.0 release is
scheduled for Summer of 2003.
What about streaming in Ogg Vorbis format?
Streaming is an important component of Vorbis. The format has
been designed from the ground-up to be easily streamable. The
designers of Vorbis are working alongside the creators of
Icecast streaming media software to make Icecast Vorbis-compatible.
We are also working on player support for streaming Ogg files.
Streaming Ogg files from the web will be supported by the player
plugins at the 1.0 Vorbis release.
What software and hardware support Ogg Vorbis?
Ogg Vorbis encoding and/or playback is now native in a wide
variety of popular software. It's included in popular players
such as WinAmp, Sonique, FreeAmp for Windows, and Unsanity Echo
for MacOS. It's also supported in popular audio applications
such as CDex, Siren Jukebox, and GoldWave. For a more complete
list, refer to our software page. Ogg Vorbis is not supported by
any publicly-available hardware yet, but portable playback is
possible for Sharp Zaurus owners by purchasing tkcPlayer
software from TheKompany.
Can I bundle Vorbis and another media type (like text lyrics
or pictures) in the same file?
Yes. The Ogg container format was designed to allow different
media types to be multiplexed together. In the future, Ogg
movies will most likely consist of a Vorbis audio track and a
video track (using Tarkin, VP3 or some other video codec) inside
of a single Ogg file. Some preliminary work has been done to put
MNG and MIDI content into Ogg files as well. Experimental code
is available in the ogg-tools module in the Xiph.org CVS
repository. Programmers working on such extensions can discuss
issues and questions on the vorbis-dev mailing list.
What other unique features does Ogg Vorbis have?
Vorbis has a well defined comment header that is easy to use and
extensible and obviates the need for clunky hacks like ID3 tags.
Vorbis has bitrate scaling - a feature that lets you adjust the
bitrate of a Vorbis file or stream without reencoding; just chop
the packets up in the sizes you want them. Vorbis files can be
sliced and edited with sample granularity. Vorbis has support
for many channels, not just 1 or 2. Vorbis files can be
logically chained together.