Vorbis
File name extension	. A filename extension is a suffix to the name of a Computer file applied to indicate the encoding convention ( File format) of its contents ogg . oga [1]
Internet media type	audio/ogg
Developed by	Xiph.Org Foundation
Type of format	Audio codec
Contained by	Ogg

Vorbis is a free and open source, lossy audio codec project headed by the Xiph.Org Foundation and intended to serve as a replacement for MP3. An Internet media type, originally called a MIME type after MIME and sometimes a Content-type after the name of a header in several protocols whose value The XiphOrg Foundation is a 501(c(3 Non-profit organization dedicated to producing free Multimedia formats and tools An audio codec is a Hardware device or a Computer program that compresses/decompresses Digital audio data according to a given Audio file To learn how to create video or audio files for Wikipedia and its sister projects check WikipediaCreation and usage of media files. Free software or software libre is Software that can be used studied and modified without restriction and which can be copied and redistributed in modified or unmodified Open source software (OSS began as a marketing campaign for Free software. A lossy compression method is one where compressing data and then decompressing it retrieves data that may well be different from the original but is close enough to be useful A codec is a device or program capable of encoding and/or decoding a Digital Data stream or signal. The XiphOrg Foundation is a 501(c(3 Non-profit organization dedicated to producing free Multimedia formats and tools MPEG-1 Audio Layer 3, more commonly referred to as MP3, is a Digital audio encoding format using a form of Lossy data compression ^[2] It is most commonly used in conjunction with the Ogg container and is therefore called Ogg Vorbis. To learn how to create video or audio files for Wikipedia and its sister projects check WikipediaCreation and usage of media files. A container format is a computer file format that can contain various types of data compressed by means of standardized audio/video codecs.

Vorbis development began following a September 1998 letter from Fraunhofer Gesellschaft announcing plans to charge licensing fees for the MP3 audio format. The Fraunhofer Society (Fraunhofer-Gesellschaft is a German research organization with 58 institutes spread throughout Germany each focusing on different fields of applied Soon after, founder Christopher "Monty" Montgomery commenced work on the project and was assisted by a growing number of other developers. Christopher "Chris" Montgomery is the creator of the Ogg Free Software container format and Vorbis audio codec and others and the founder of The Xiph They continued refining the source code until a stable version 1. In Computer science, source code (commonly just source or code) is any sequence of statements or declarations written in some Human-readable 0 of the codec was released on July 19, 2002. Events 711 - Muslim forces under Tariq ibn Ziyad defeat the Visigoths led by their king Roderic. See also 2002 (disambiguation Year 2002 ( MMII) was a Common year starting on Tuesday of the Gregorian calendar.

The latest official version is 1. 2. 0 released on 2007-07-25, but there are some fine-tuned forks, most notably aoTuV, that offer better audio quality, particularly at low bitrates. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 285 - Diocletian appoints Maximian as Caesar, co-ruler In Software engineering, a project fork happens when developers take a copy of Source code from one software package and start independent development Work is in progress to merge back those improvements. Source code (called libvorbis) for the Xiph. Org Foundation release is available from the official download page. ^[3]

Name

"Vorbis" is named after a Discworld character, Exquisitor Vorbis in Small Gods, by Terry Pratchett. Discworld is a comedic Fantasy Book series by the British author Terry Pratchett, set on the Discworld, a flat This article contains brief biographies for characters from Terry Pratchett 's Discworld series Small Gods is the thirteenth of Terry Pratchett 's popular Discworld Novels, published in 1992 Terence David John Pratchett, OBE (born 28 April 1948 is an English fantasy, Science fiction, and children's author. Coincidentally, Nanny Ogg is another Discworld character, a witch who appears in several books including Witches Abroad, though the Ogg format was not named after her. Gytha Ogg (usually called Nanny Ogg) is a character from Terry Pratchett 's Discworld series Witches Abroad is the twelfth Discworld novel by Terry Pratchett, originally published in 1991 To learn how to create video or audio files for Wikipedia and its sister projects check WikipediaCreation and usage of media files. "Ogg" is in fact derived from ogging, jargon that arose in the computer game Netrek. Ogging is term for a tactic developed for the online multiplayer game Netrek. For Wikipedia jargon see WikipediaGlossary. For hacker slang see Jargon File. Netrek is an Internet game for up to 16 players It is free to download and play written almost entirely in Open source software, is Cross platform ^[4]

Usage

The Amarok software playing a Vorbis-encoded song. Amarok (ˈæməɹɒk is a Free software music player for Linux or other varieties of Unix. Also demonstrates Unicode support. In Computing, Unicode is an Industry standard allowing Computers to consistently represent and manipulate text expressed in most of the world's

The Vorbis format has proven popular among supporters of Free software. Free software or software libre is Software that can be used studied and modified without restriction and which can be copied and redistributed in modified or unmodified ^[5] They argue that its higher fidelity and completely free nature, unencumbered by patents, make it a well-suited replacement for patented and restricted formats like MP3. However, MP3 has been widely used since the late-1990s and as of 2008, continues to remain popular in the consumer electronics industry.

Vorbis has different uses for consumer products. Many video game titles such as 18 Wheels of Steel, Unreal Tournament, Mafia: The City of Lost Heaven and Grand Theft Auto: San Andreas store in-game audio as Vorbis. A video game is a Game that involves interaction with a User interface to generate visual feedback on a video device. 18 Wheels of Steel (sometimes abbreviated as 18 WoS) is a series of Trucking Simulators published by ValuSoft and developed by SCS Software Unreal Tournament is a First-person shooter Video game co-developed by Epic Games and Digital Extremes. Mafia The City of Lost Heaven is a sandbox-style Third-person shooter Video game initially made for PC and released in. Grand Theft Auto San Andreas is a sandbox-style action-adventure computer and Video game developed by Rockstar North Popular software players support Vorbis playback either natively or through an external plugin. A number of Web sites use it, such as Jamendo and Mindawn, as well as several national radio stations like CBC Radio, JazzRadio, and Virgin Radio. Jamendo is a music platform and community combining Creative Commons / Free Art License licensed music BitTorrent and Mindawn is an Online music store that unlike most major services of its type offers its songs in Lossless FLAC format without Copy protection CBC Radio is the Radio division of the Canadian Broadcasting Corporation. Virgin Radio is a brand owned by the Virgin Group used by a number of different radio stations worldwide under licence from Virgin

Codec comparisons

For many applications, Vorbis has clear advantages over other lossy audio codecs in that it is patent-free and has free and open-source implementations and therefore is free to use, implement, or modify as one sees fit, yet produces smaller files than most other codecs at equivalent or higher quality. The following is a list of Codecs Audio codecs See also Audio codec Non-compression formats Audio Interchange File Format Open source software (OSS began as a marketing campaign for Free software. ^[6][7]

Listening tests have attempted to find the best quality lossy audio codecs at certain bitrates. In Telecommunications and Computing, bitrate (sometimes written bit rate, data rate or as a Variable R or f b Some conclusions made by recent listening tests:

• Low bitrate (less than 64 kbit/s): the most recent public multiformat test at 48 kbit/s shows that aoTuV Vorbis has a better quality than WMA and LC-AAC, the same quality of WMA Professional, and a lower quality than HE-AAC. Windows Media Audio ( WMA) is an Audio data compression technology developed by Microsoft. Advanced Audio Coding ( AAC) is a standardized lossy compression and encoding scheme for Digital audio. Windows Media Audio ( WMA) is an Audio data compression technology developed by Microsoft. High Efficiency AAC ( HE-AAC) is a Lossy data compression scheme for Digital audio. ^[8]
• Mid to low bitrates (less than 128 kbit/s down to 64 kb/s): private tests at 80 kbit/s and 96 kbit/s shows that aoTuV Vorbis has a better quality than other lossy audio codecs (LC-AAC, HE-AAC, MP3, MPC, WMA). Advanced Audio Coding ( AAC) is a standardized lossy compression and encoding scheme for Digital audio. High Efficiency AAC ( HE-AAC) is a Lossy data compression scheme for Digital audio. MPEG-1 Audio Layer 3, more commonly referred to as MP3, is a Digital audio encoding format using a form of Lossy data compression Musepack or MPC is an Open source lossy audio codec, specifically optimized for transparent compression of stereo audio at bitrates of 160&ndash180 Windows Media Audio ( WMA) is an Audio data compression technology developed by Microsoft. ^{[9] [10]}
• Mid bitrate (128kb/s): most recent public multiformat test at 128 kbit/s shows a four-way tie between aoTuV Vorbis, LAME-encoded MP3, WMA Pro, and QuickTime AAC, with each codec essentially transparent (sounds identical to the original music file). LAME is an Open source application used to encode audio into the MP3 file format Windows Media Audio ( WMA) is an Audio data compression technology developed by Microsoft. QuickTime is a Multimedia framework developed by Apple Inc, capable of handling various formats of Digital video, Media clips sound text Advanced Audio Coding ( AAC) is a standardized lossy compression and encoding scheme for Digital audio. ^[11]
• High bitrates (more than 128 kb/s): most people do not hear significant differences. However, trained listeners can often hear significant differences between codecs at identical bitrates, and aoTuV Vorbis performs better than LC-AAC, MP3, and MPC. Advanced Audio Coding ( AAC) is a standardized lossy compression and encoding scheme for Digital audio. MPEG-1 Audio Layer 3, more commonly referred to as MP3, is a Digital audio encoding format using a form of Lossy data compression Musepack or MPC is an Open source lossy audio codec, specifically optimized for transparent compression of stereo audio at bitrates of 160&ndash180 ^[12]

Many of these results, however, are difficult to keep up to date due to the ever-evolving nature of the codecs.

Listening tests

See also: codec listening test#Results

Listening tests are normally carried out as ABX tests, i. A codec listening test is a Scientific study designed to compare two or more lossy audio Codecs usually with respect to perceived An ABX test is a method of comparing two kinds of sensory stimuli to identify detectable differences e. , the listener has to identify an unknown sample X as being A or B, with A (the original) and B (the encoded version) available for reference. The outcome of a test must be statistically significant. This setup ensures that the listener is not biased by his/her expectations, and that the outcome is very unlikely to be the result of chance. If sample X can be identified reliably, the listener can assign a score as a subjective judgement of the quality. Otherwise, the encoded version is considered to be transparent. Below are links to several listening test results.

• 2005-2006 Public group test of Lame MP3, Vorbis AoTuV, iTunes AAC, Nero AAC, and WMA Pro at ~135 kbit/s nominal. Results suggest that further group testing at this bitrate is unnecessary because all codecs are statistically tied near transparency. ^[11]
• 2005, July comparison - AAC vs MP3 vs Vorbis vs WMA at 80 kbit/s. States that aoTuV beta 4 is the best encoder for either classical or various music in this bitrate, and that its quality is comparable to the LAME ABR MP3 at 128 kbit/s. LAME is an Open source application used to encode audio into the MP3 file format Average bitrate refers to the average amount of data transferredper unit of time usually measured per second ^[9]
• 2005, August comparison - AAC vs MP3 vs Vorbis vs WMA at 96 kbit/s. States that aoTuV beta 4 and AAC are tied as the best encoders for classical music in this bitrate, while aoTuV beta 4 is the best encoder for pop music, even better than LAME at 128 kbit/s. ^[10]
• 2005, August comparison - MPC vs VORBIS vs MP3 vs AAC at 180 kbit/s. An audiophile listening test, which states that, for classical music, aoTuV beta 4 has 93% percent probability of being the best encoder, tied with MPC. An audiophile, from Latin audio "I hear" and Greek philos "loving" is an audio reproduction enthusiast who typically listens MPC is tied with both Vorbis, in the first place, and LAME in the second. ^[12]

Technical details

Given 44. 1 kHz (standard CD audio sampling frequency) stereo input, the encoder will produce output from roughly 45 to 500 kbit/s (32 to 500 kbit/s for aoTuV tunings) depending on the specified quality setting. The hertz (symbol Hz) is a measure of Frequency, informally defined as the number of events occurring per Second. A Compact Disc (also known as a CD) is an Optical disc used to store digital data, originally developed for storing digital audio Sampling theorem The Nyquist–Shannon sampling theorem states that perfect reconstruction Quality settings run from -1 to 10 (-2 to 10 for aoTuV tunings). Files encoded with a given quality setting should have the same quality of sound in all versions of the encoder, but newer versions should be able to achieve that quality with a lower bitrate. The bitrates mentioned above are only approximate; Vorbis is inherently variable-bitrate (VBR), so bitrate may vary considerably from sample to sample. Variable bitrate ( VBR) or less commonly variable bit rate, is a term used in Telecommunications and Computing that relates to the

Vorbis uses the modified discrete cosine transform (MDCT) for converting sound data from the time domain to the frequency domain. The modified discrete cosine transform (MDCT is a Fourier-related transform based on the type-IV Discrete cosine transform (DCT-IV with the additional property Time domain is a term used to describe the analysis of mathematical functions or physical signals with respect to Time. Frequency domain is a term used to describe the analysis of Mathematical functions or signals with respect to frequency 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. In Signal theory, the noise floor is the measure of the signal created from the sum of all the Noise sources and unwanted signals within a measurement system In Information theory an entropy encoding is a lossless Data compression scheme that is independent of the specific characteristics of the medium In Cryptography, a codebook is a document used for implementing a code. Vector quantization is a classical Quantization technique from Signal processing which allows the modeling of probability density functions by the distribution of 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), which many people find more pleasant than the metallic warbling in the MP3 format. The sound of the compression artifacts at low bitrates can be perhaps described as reverberations in an amphithreatre or a room.

Vorbis aims to be more efficient than MP3, with transparency being available at lower bitrates. In Data compression or Psychoacoustics, transparency is the ideal result of Lossy data compression.

Various tuned versions of the encoder (Garf, aoTuV or MegaMix) attempt to provide better sound at a specified quality setting, usually by dealing with certain problematic waveforms by temporarily increasing the bitrate. The most consistently cited problem with Vorbis is pre-echo, a faint copy of a sharp attack that occurs just before the actual sound (the sound of castanets is commonly cited as causing this effect). Pre-echo is an audio Compression artifact where a sound is heard before it occurs (hence the name Castanets are Percussion instrument ( Idiophone) much used in Moorish, Ottoman, Ancient Roman, Italian, Spanish Most of the tuned versions of Vorbis attempt to fix this problem and to increase the sound quality of lower quality settings (-q-2 through -q4). Some tuning suggestions created by the Vorbis user community (especially the aoTuV beta 2 tunings) have been incorporated into the 1. 1. 0 release. ^[13]

The Vorbis format supports bitrate peeling for reducing the bitrate of already encoded files, and an experimental implementation is available. Bitrate Peeling is a technique used in Ogg Vorbis audio encoded streams, wherein a stream can be encoded at one bitrate ^[14] However, encoding at the lower bitrate will result in better audio quality than this experimental bitrate peeler.

Vorbis streams can be encapsulated in other media container formats besides Ogg. A container format is a computer file format that can contain various types of data compressed by means of standardized audio/video codecs. ^[15] A commonly used alternative is Matroska. The Matroska Multimedia Container is an Open standard free Container format, a File format that can hold an unlimited number of video audio

Metadata

Vorbis metadata, called comments, support metadata 'tags' similar to those implemented in the ID3 standard for MP3. Metadata ( meta data, or sometimes metainformation) is "data about data" of any sort in any media A Vorbis comment is a Metadata container used in the Vorbis, FLAC, and Speex Audio file formats It allows information such as the ID3 is a Metadata container most often used in conjunction with the MP3 Audio file format. The metadata is stored in a vector of eight-bit-clean strings of arbitrary length and size. Eight-bit clean describes a Computer system that correctly handles 8-bit character sets, such as the ISO 8859 series and the UTF-8 The size of the vector and the size of each string in bytes is limited to 2³²-1 (about 4. 3 billion, or any integer that can be expressed in 32 bits). This vector is stored in the second header packet that begins a Vorbis bitstream. ^[16]

The strings are assumed to be encoded as UTF-8. UTF-8 (8- Bit UCS / Unicode Transformation Format) is a variable-length Character encoding for Unicode. Music tags are typically implemented as strings of the form "[TAG]=[VALUE]", for instance, "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 discnumber and Replay Gain information. Replay Gain is a proposed standard published in 2001 to normalize the perceived Loudness of computer audio formats such as MP3 and

Licensing

Knowledge of Vorbis's specifications is in the public domain. The public domain is a range of abstract materials &ndash commonly referred to as Intellectual property &ndash which are not owned or controlled by anyone 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. BSD licenses represent a family of Permissive free software licences. 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 GNU Lesser General Public License (formerly the GNU Library General Public License) or LGPL is a Free software license published by the Free Software Richard Matthew Stallman (born March 16 1953 often abbreviated " rms " is an American software freedom activist ^[17] The Xiph.Org Foundation states that Vorbis, like all its developments, is completely free from the licensing or patent issues raised by other proprietary formats such as MP3. The XiphOrg Foundation is a 501(c(3 Non-profit organization dedicated to producing free Multimedia formats and tools Software patent does not have a universally accepted definition Proprietary software is Computer software on which the producer has set restrictions on use private modification copying, or republishing. MPEG-1 Audio Layer 3, more commonly referred to as MP3, is a Digital audio encoding format using a form of Lossy data compression 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. ^[18]

The Xiph. Org Foundation maintains that it was privately issued a legal opinion subject to attorney-client privilege. Attorney-client privilege is a legal concept that protects communications between a client and his or her Attorney and keeps those communications confidential It 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 cannot be resolved outside of a court of law. Some Vorbis proponents have derided the uncertainty concerning the patent status as "FUD": misinformation spread by large companies with a vested interest. Fear uncertainty and doubt ( FUD) is a tactic of Rhetoric and Fallacy used in Sales, Marketing, Public relations and politics

Vorbis is supported by several large digital audio player manufacturers such as Samsung, Rio, Neuros Technology, Cowon, and iriver. A digital audio player, more commonly referred to as an MP3 player, is a Consumer electronics device that stores organizes and plays audio files Some The Samsung Group ( Korean:, Samsung Guerup) is South Korea 's largest company or Chaebol and the world's largest conglomerate Rio was the Brand name of a line of Digital audio players best known for producing the "Diamond Rio" model that was the impetus for a lawsuit Neuros Technology is a Chicago Illinois -based company that produces a number of audio and video devices with the brand name Neuros Cowon Systems Inc is a South Korean electronics company established in 1995 iriver (formerly iRiver) is a brand and division of ReignCom, manufacturer of Digital audio players and other portable Many feel that the growing support for the Vorbis codec within the industry supports their interpretation of its patent status, as multinational corporations are unlikely to distribute software with questionable legal status. The same could be said about its growing popularity in other commercial enterprises like mainstream computer games.

Hardware and software 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-style license). Tremor by the XiphOrg Foundation is a fixed-point version of the Vorbis decoder for those platforms without Floating point operations In Computing, a fixed-point number representation is a Real data type for a number that has a fixed number of digits after (and sometimes also before the In Computing, floating point describes a system for numerical representation in which a string of digits (or Bits represents a Real number. Events 44 BC - Pharaoh Cleopatra VII of Egypt declares her son co-ruler as Ptolemy XV Caesarion. See also 2002 (disambiguation Year 2002 ( MMII) was a Common year starting on Tuesday of the Gregorian calendar. BSD licenses represent a family of Permissive free software licences. ^[19] 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 an intention to produce Vorbis-compliant devices, and new Vorbis devices seem to be appearing at a steady rate, especially in South Korea, although availability may differ from country to country. South Korea, officially the Republic of Korea and often referred to as Korea ( Korean: 대한민국 tɛː

Many high-end digital audio players such as Cowon's popular D2 and iAudio X5 ship with full ogg support. Cowon Systems Inc is a South Korean electronics company established in 1995 Cowon Systems Inc is a South Korean electronics company established in 1995 iAUDIO is a brand of portable Digital audio player produced by Cowon. Although many digital audio players such as Apple's iPod do not natively support Vorbis, through the use of Rockbox, an open-source firmware project, many become capable of decoding Vorbis files. iPod is a popular brand of Portable media players designed and marketed by Apple Inc Rockbox is a Free software replacement for the Firmware held on various forms of Digital audio players (DAPs Support continues to grow; in May 2008 Sandisk added Vorbis capability to the 1.01.29 firmware for the Sansa Clip player. The Xiph. Org Foundation wiki has an up-to-date list of Vorbis-supporting hardware, such as portables, PDAs, and microchips. ^[20]

Software

Software supporting Vorbis exists for many platforms. Although Apple iTunes does not natively support Vorbis, the Xiph. Apple Inc, ( formerly Apple Computer Inc, is an American Multinational corporation with a focus on designing and manufacturing Consumer electronics iTunes is a proprietary digital media player application introduced by Apple Inc Org Foundation provides a QuickTime component^[21] which can be used in iTunes and QuickTime on both Microsoft Windows and Mac OS. Microsoft Windows is a series of Software Operating systems and Graphical user interfaces produced by Microsoft. Mac OS is the trademarked name for a series of Graphical user interface -based Operating systems developed by Apple Inc On Windows, DirectShow filters exist^[22] to decode Vorbis in multimedia players like Windows Media Player and others which support DirectShow. Windows Media Player ( WMP) is a digital media player and media library application developed by Microsoft that is used for playing DirectShow (sometimes abbreviated as DS or DShow) codename Quartz, is a Multimedia framework and API produced by Microsoft Vorbis is well-supported on the Linux platform in programs like XMMS, xine, and many more. Linux (commonly pronounced ˈlɪnəks The X Multimedia System ( XMMS) is a Free software audio player very similar to Winamp, that runs on many Unix-like Operating xine (officially ksin is a Multimedia playback engine for Unix-like Operating systems released under the GNU General Public License. More information about Vorbis-supporting software can be found at the Xiph. Org Foundation wiki. ^[23] Users can test these programs using the list of Vorbis audio streams available on the same wiki. ^[24] The ever-popular Winamp can also play ". Winamp is a proprietary media player written by Nullsoft, now a subsidiary of Time Warner. ogg" vorbis files.

Implementations

Because of Vorbis's free and open nature, developers are free to write compliant encoders and decoders.

Official

The Xiph. Org Foundation's reference implementation is free and open source, and licensed under the BSD License and the GNU Lesser General Public License.

aoTuV

Modified versions of the reference encoder are also available: aoTuV is a version that has received quality tweaks since the release of libVorbis 1. 0; previous changes from aoTuV (Beta2) have been merged back into the Xiph. Org Foundation's libVorbis 1. 1. Lancer is a modified version of aoTuV focusing on encoding speed. Current version: aoTuV Beta5. 5 (2008/03/31)

Tremor

Main article: Tremor (software)

Tremor is an implementation of a Vorbis decoder using fixed-point arithmetic. Tremor by the XiphOrg Foundation is a fixed-point version of the Vorbis decoder for those platforms without Floating point operations It is intended for environments when a floating-point arithmetic unit is unavailable. The Xiph. Org Foundation has expressed interest in modifying Tremor into a floating-point version, which would replace the current floating-point reference decoder. ^[25]

FFmpeg

Main article: FFmpeg

The libavcodec library contains an LGPL-licensed Vorbis decoder that is faster than the reference implementation. FFmpeg is a computer program that can record convert and stream digital audio and Video in numerous formats libavcodec is a Free software / Open source LGPL -licensed library of Codecs for encoding and decoding video and audio data it is written in the ^[26]

See also

• Comparison of audio codecs
• FreeCast, peer-to-peer Vorbis streaming
• Juce, cross-platform C++ toolkit with embedded Vorbis support
• Ogg bitstream format
• PocketOgg: a Vorbis player program for Windows CE for Pocket PC
• Sb0, a file format related to Vorbis, used in certain Ubisoft games
• Vorbis comment, metadata format used by Vorbis
• XSPF, playlist format
• Xiph QuickTime Components, official QuickTime implementation

References

External links

• The Xiph.Org Foundation
• Vorbis site - Xiph reference implementation
  • Listening test comparing Vorbis to MP3, RealAudio, WMA, etc.
  • Vorbis wiki — mostly developer information
  • List of video games using Vorbis
  • Vorbis FAQ
  • Vorbis documentation
  • Cross Reference and Data Structures
• Other encoder / decoder implementation:
  • List of decoders
  • List of encoders
  • Xiph reference implementation
  • aoTuV - aoTuV Vorbis tuned implementation
  • Vorbis acceleration project - Optimized versions of aoTuV Vorbis encoder and other SSE/MultiThread optimizations
  • Fixed-point version of the Vorbis decoder
• Software / hardware supporting Vorbis:
  • List of encoder frontends
  • RealPlayer Plug-In
  • Vorbis binaries at Rarewares
  • Vorbis DirectShow filter for Windows
  • QuickTime component for QuickTime and iTunes
• Other useful links:
  • Modified discrete cosine transform Description
  • Christopher "Monty" Montgomery (main developer) interview, slashdot.org
  • Vorbis at Hydrogenaudio wiki
  • jamendo.com : Largest archive of Creative Commons licensed Vorbis music
  • An Introduction to Compressed Audio with Vorbis