Vorbis is a free and open-source software project headed by the Xiph.Org Foundation. The project produces an audio coding format and software reference encoder/decoder (codec) for lossy audio compression, libvorbis.
Version 1.0 of Vorbis was released in May 2000.
Name
Vorbis is named after the character Exquisitor Vorbis in the
Discworld novel
Small Gods by
Terry Pratchett. The
Ogg format is named after
ogging,
jargon from the computer game
Netrek.
Development
Vorbis is a continuation of audio compression development started in 1993 by
Chris Montgomery.
Intensive development began following a September 1998 letter from the Fraunhofer Society announcing plans to charge licensing fees for the MP3 audio format.
The Vorbis project started as part of the Xiphophorus company's Ogg project (also known as OggSquish multimedia project).
Chris Montgomery began work on the project and was assisted by a growing number of other developers. They continued refining the
source code until the Vorbis file format was frozen for 1.0 in May 2000.
Originally licensed as
LGPL, in 2001 the Vorbis license was changed to the
BSD license to encourage adoption, with the endorsement of
Richard Stallman.
[ February 2001 on xiph.org "With the Beta 4 release, the Ogg Vorbis libraries have moved to the BSD license. The change from LGPL to BSD was made to enable the use of Ogg Vorbis in all forms of software and hardware. Jack Moffitt says, "We are changing the license in response to feedback from many parties. It has become clear to us that adoption of Ogg Vorbis will be accelerated even further by the use of a less restrictive license that is friendlier toward proprietary software and hardware systems. We want everyone to be able to use Ogg Vorbis.""][ RMS on license change on lwn.net] A stable version (1.0) of the reference software was released on July 19, 2002.
Since February 2013,
Usage
Vorbis faces competition from other audio formats, such as MP3. Though Vorbis is technically superior (addressing many of the limitations inherent to the MP3 design), MP3 has a far higher public profile.
Because Vorbis does not have financial support from large organisations, support for the format is not as widespread, though programs such as Audacity can convert to more popular formats,
and support in games has gradually improved.
The Vorbis format has proven popular among supporters of free software.
Vorbis has different uses for consumer products. Many store in-game audio as Vorbis, including , , , Minecraft, and World of Warcraft, among others.[WikiProject Spoken Wikipedia, Retrieved 2009]
Technical details
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| + Vorbis nominal bitrate at quality levels for 44.1 kHz stereo input. The new libvorbis v1.2 usually compresses better than these values (effective bitrate may vary). |
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| -q-1 | 45 kbit/s | 48 kbit/s |
| -q0 | 64 kbit/s |
| -q1 | 80 kbit/s |
| -q2 | 96 kbit/s |
| -q3 | 112 kbit/s |
| -q4 | 128 kbit/s |
| -q5 | 160 kbit/s |
| -q6 | 192 kbit/s |
| -q7 | 224 kbit/s |
| -q8 | 256 kbit/s |
| -q9 | 320 kbit/s |
| -q10 | 500 kbit/s |
Outline of coder algorithm
Vorbis I is a forward-adaptive monolithic transform codec based on the modified discrete cosine transform (MDCT).
Vorbis uses the modified discrete cosine transform for converting sound data from the
time domain to the
frequency domain. The resulting frequency-domain data is broken into
noise floor and residue components, and then quantized and
entropy coded using a
codebook-based vector quantization algorithm. The decompression algorithm reverses these stages. The noise-floor approach gives Vorbis its characteristic analog noise-like failure mode when the bitrate is too low to encode the audio without perceptible loss. The sound of compression artifacts at low bitrates is similar to
Reverberation in a large space.
Container formats
Vorbis streams can be encapsulated in other media container formats besides Ogg.
A commonly used alternative is
Matroska. It is also used in
WebM, a container format based on a subset of Matroska.
Vorbis streams can also be encapsulated in an RTP payload format.
Metadata
Vorbis
metadata, called
, supports metadata tags similar to those implemented in the ID3 standard for MP3. The metadata is stored in a vector of byte strings of arbitrary length and size. The size of the vector and the size of each string in bytes is limited to 2
32 − 1 (about 4.3 billion, or any positive integer that can be expressed in 32 bits). This vector is stored in the second header packet that begins a Vorbis bitstream.
The strings are assumed to be encoded as UTF-8. Music tags are typically implemented as strings of the form "TAG=VALUE", for instance, "ARTIST=The John Smith Band". The tag names are case-insensitive, thus typing "ARTIST=The John Smith Band" would be the same as "artist=The John Smith Band". Like the current version of ID3, users and encoding software are free to use whichever tags are appropriate for the content. For example, an encoder could use localized tag labels, live music tracks might contain a "Venue=" tag or files could have multiple genre definitions. Most applications also support common de facto standards such as disc number and ReplayGain information.
Variants
is a notable fork which adds support for encoding at lower bitrates.
aoTuV's changes were intended to be merged into the reference encoder periodically, but that only happened once in libvorbis 1.1,
due to future merges being a "task that requires uninterrupted time, something I
Licensing
Knowledge of Vorbis' specifications is in the
public domain.
Concerning the specification itself, the Xiph.Org Foundation reserves the right to set the Vorbis specification and certify compliance. Its libraries are released under the revised 3-clause
BSD License and its tools are released under the GNU General Public License. The libraries were originally released under the GNU Lesser General Public Licence, but a BSD license was later chosen with the endorsement of
Richard Stallman.
The Xiph.Org Foundation states that Vorbis, like all its developments, is completely free from the licensing or
Software patent issues raised by proprietary formats. Although the Xiph.Org Foundation states it has conducted a patent search that supports its claims, outside parties (notably engineers working on rival formats) have expressed doubt that Vorbis is free of patented technology.
The Xiph.Org Foundation has not released an official statement on the patent status of Vorbis, pointing out that such a statement is technically impossible due to the number and scope of patents in existence and the questionable validity of many of them. Such issues can only be resolved by a court of law.
Vorbis is supported by several large digital audio player manufacturers such as Samsung, SanDisk, Rio, Neuros Technology, Cowon, and iriver.
Support
Hardware
Tremor, a version of the Vorbis decoder which uses fixed-point arithmetic (rather than
floating point), was made available to the public on September 2, 2002 (also under a
BSD License).
Tremor, or platform-specific versions based on it, is more suited to implementation on the limited facilities available in commercial portable players. A number of versions that make adjustments for specific platforms and include customized optimizations for given embedded microprocessors have been produced. Several hardware manufacturers have expressed intentions to produce Vorbis-compliant devices and new Vorbis devices seem to be appearing at a steady rate.
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Sailfish OS devices
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Tizen devices
-
Openmoko Neo 1973 and Neo Freerunner
-
Devices based on Google's Android platform support Ogg Vorbis media files.
-
Digital audio players such as Cowon's D2 and iAudio X5 ship with Ogg Vorbis support.
-
Samsung YP series of digital audio players
-
The majority of iriver devices provide Ogg Vorbis support up to Q10 bitrates.
-
Cowon C2 (Ogg and FLAC support)
-
Some SanDisk portable media players including the Fuze and Clip
-
Meizu's M6 and M3 Digital Audio Players
-
S1 MP3 Players also supports Ogg Vorbis since at least 2006, though this is not typically listed on the player's packaging.
-
GamePark Holding's Linux based portable gaming consoles (GP32, GP2X F100-F200, GP2X Wiz) officially support Ogg Vorbis.
-
RIM BlackBerry 9800 "Torch" and 9670 "Style"
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HP TouchPad was given support for Ogg Vorbis with the webOS 3.0.4 update
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Denon SC5000 Prime media player
-
Ultra HD Blu-ray players support decoding of 4K resolution VP8/VP9 video with Ogg Vorbis audio.
Apple's iPod does not natively support Vorbis but through the use of Rockbox, an open-source firmware project, is capable of decoding Vorbis files on certain models. Similar statements apply to other devices capable of running Rockbox, as well. The Xiph.Org Foundation wiki has an up-to-date list of Vorbis-supporting hardware, such as portables, PDAs, and microchips.
Application software
Software supporting Vorbis exists for many platforms. The multi-platform open-source VLC media player and
MPlayer can play Ogg Vorbis files, as can
Winamp and foobar2000. Windows Media Player does not natively support Vorbis; however,
DirectShow filters exist to decode Vorbis in Windows Media Player and other Windows multimedia players that support DirectShow.
Vorbis is also supported in the multi-platform audio editing software Audacity, in the multi-platform multimedia frameworks
FFmpeg,
GStreamer and Helix DNA. Vorbis is well-supported on the
Linux platform in programs like
XMMS,
xine, Amarok. A list of Vorbis-supporting software can be found at the Xiph.Org Foundation wiki and Vorbis.com website.
Users can test these programs using the list of Vorbis audio streams available on the same wiki.
For more information about support in software media players there is a comparison of media players available.
Some newer [[Ubisoft]] games use Vorbis files renamed with the filename extension . It can therefore be played using a compatible player, although sometimes one must force a different [[sampling rate]] to hear it correctly. A number of tools are available for extracting sound from [[archived files|file archiver]] such as the .m4b of ''[[Myst IV: Revelation]]''.
As originally recommended by HTML 5, these natively support Vorbis audio (without a plug-in) using the ogginfo element: Mozilla Firefox 3.5 (and later versions),
The game design software RPG Maker MV, released in October 2015, is the first version of that program to drop MP3 support in favor of Ogg Vorbis.
In October 2017, Microsoft released support for Ogg media container, and Theora and Vorbis media formats as an optional add-on to Windows 10 and Xbox One, available for free in the Microsoft Store.
| + Vorbis support by different operating systems |
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See also
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Comparison of audio coding formats
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Icecast, streaming media server which currently supports Ogg (Vorbis and Theora), Opus and WebM streams.
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JUCE, cross-platform C++ toolkit with embedded Vorbis support
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Ogg bitstream container
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Opus, audio format by Xiph that is biased towards latency
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Vorbis comment, metadata format used by Vorbis
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XML Shareable Playlist Format, playlist format
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Xiph QuickTime Components, official QuickTime implementation
Notes
External links
