Ogg is a

free Free may refer to: Concept * Freedom, having the ability to act or change without constraint * Emancipate, to procure political rights, as for a disenfranchised group * Free will, control exercised by rational agents over their actions and decis ...

open Open or OPEN may refer to: Music * Open (band) Open is a band. Background Drummer Pete Neville has been involved in the Sydney/Australian music scene for a number of years. He has recently completed a Masters in screen music at the Australia ...

container format maintained by the Xiph.Org Foundation. The authors of the Ogg format state that it is unrestricted by

software patent A software patent is a patent on a piece of software, such as a computer program, Library (computing), libraries, user interface, or algorithm. Background A patent is a set of exclusionary rights granted by a State (polity), state to a patent h ...

s and is designed to provide for efficient

streaming Streaming media is multimedia Multimedia is a form of communication that combines different content forms such as text, audio, images, animations, or video into a single presentation, in contrast to traditional mass media, such as printed ...

and manipulation of high-quality

digital multimedia Multimedia is a form of communication that combines different content forms such as text Text may refer to: Written word * Text (literary theory) In literary theory, a text is any object that can ...

. Its name is derived from "ogging",

jargon Jargon is the specialized terminology associated with a particular field or area of activity. Jargon is normally employed in a particular Context (language use), communicative context and may not be well understood outside that context. The conte ...

from the computer game ''

Netrek ''Netrek'' is an Internet game An online game is a video game that is either partially or primarily played through the Internet or any other computer network available. Online games are ubiquitous on modern gaming platforms, including PC game, ...

''. The Ogg container format can

multiplex Multiplex may refer to: * Multiplex (automobile), a former American car make * Multiplex (comics), a DC comic book supervillain * Multiplex communication or multiplexing, combining many signals into a single transmission circuit or channel ** Multi ...

a number of independent

streams In computer networking A computer network is a set of computer A computer is a machine that can be programmed to carry out sequences of arithmetic or logical operations automatically. Modern computers can perform generic sets of opera ...

for

audio Audio most commonly refers to sound In physics Physics (from grc, φυσική (ἐπιστήμη), physikḗ (epistḗmē), knowledge of nature, from ''phýsis'' 'nature'), , is the natural science that studies matter, its Motion ( ...

audio

video Video is an electronic Electronic may refer to: *Electronics Electronics comprises the physics, engineering, technology and applications that deal with the emission, flow and control of electrons in vacuum and matter. It uses active d ...

video

, text (such as

subtitles Subtitles are text Text may refer to: Written word * Text (literary theory) Text may refer to: Written word * Text (literary theory), any object that can be read, including: **Religious text, a writing that a religious tradition considers ...

), and

metadata Metadata is "data Data (; ) are individual facts, statistics, or items of information, often numeric. In a more technical sense, data are a set of values of qualitative property, qualitative or quantity, quantitative variable (research), v ...

. In the Ogg multimedia framework,

Theora Theora is a free Free may refer to: Concept * Freedom, having the ability to act or change without constraint * Emancipate, to procure political rights, as for a disenfranchised group * Free will, control exercised by rational agents over ...

provides a

lossy In information technology, lossy compression or irreversible compression is the class of data compression, data encoding methods that uses inexact approximations and partial data discarding to represent the content. These techniques are used to r ...

video layer. The audio layer is most commonly provided by the music-oriented

Vorbis Vorbis is a free and open-source software Free and open-source software (FOSS) is software Software is a collection of instructions that tell a computer A computer is a machine that can be programmed to carry out sequences of ari ...

format or its successor Opus.

Lossless Lossless compression is a class of data compression In signal processing Signal processing is an electrical engineering subfield that focuses on analysing, modifying, and synthesizing signals such as audio signal processing, sound, image ...

audio compression formats include

FLAC FLAC (; Free Lossless Audio Codec) is an audio coding format for lossless compression of digital audio, developed by the Xiph.Org Foundation, and is also the name of the free software project producing the FLAC tools, the reference software p ...

, and

OggPCM Ogg is a free file format, free, open format, open container format (digital), container format maintained by the Xiph.Org Foundation. The authors of the Ogg format state that it is unrestricted by software patents and is designed to provide fo ...

. Before 2007, the .ogg

filename extension A filename extension, file extension or file type is an identifier specified as a suffix to the name A name is a term used for identification by an external observer. They can identify a class or category of things, or a single thing, either ...

was used for all files whose content used the Ogg container format. Since 2007, the Xiph.Org Foundation recommends that .ogg only be used for Ogg Vorbis audio files. The Xiph.Org Foundation decided to create a new set of file extensions and media types to describe different types of content such as .oga for audio only files, .ogv for video with or without sound (including Theora), and .ogx for multiplexed Ogg. As of November 7, 2017, the current version of the Xiph.Org Foundation's reference implementation is libogg 1.3.3. Another version, libogg2, has been in development, but is awaiting a rewrite as of 2018. Both

software libraries In computer science Computer science deals with the theoretical foundations of information, algorithms and the architectures of its computation as well as practical techniques for their application. Computer science is the study of ...

are

free software Free software (or libre software) is computer software distributed under terms that allow users to run the software for any purpose as well as to study, change, and distribute it and any adapted versions. Free software is a matter of liberty ...

, released under the

New BSD License BSD licenses are a family of permissive free software licenses, imposing minimal restrictions on the use and distribution of covered software. This is in contrast to copyleft licenses, which have share-alike requirements. The original BSD lice ...

. Ogg reference implementation was separated from Vorbis on September 2, 2000.Xiph.Org (2002-07-19
Ogg releases - libogg-1.0.tar.gz - CHANGES
Retrieved 2009-09-01. Because the format is free, and its reference implementation is not subject to restrictions associated with

copyright Copyright is a type of intellectual property Intellectual property (IP) is a category of property Property is a system of rights that gives people legal control of valuable things, and also refers to the valuable things themselves. ...

, Ogg's various

codec A codec is a device or computer program In imperative programming, a computer program is a sequence of instructions in a programming language that a computer can execute or interpret. In declarative programming, a ''computer program'' is a Set ...

s have been incorporated into a number of different free and

proprietary {{Short pages monitor one or more METADATA_BLOCK_PICTURE=… in a ''VorbisComment'' for thumbnails and cover art have

Base64 In programming, Base64 is a group of binary-to-text encoding A binary-to-text encoding is code, encoding of data (computing), data in plain text. More precisely, it is an encoding of binary data in a sequence of character (computing), printable ...

-encoded values of the corresponding

METADATA_BLOCK_PICTURE. In other words, FLAC stores thumbnails and cover art in binary blocks—outside of the FLAC tags in a

little-endian In computing Computing is any goal-oriented activity requiring, benefiting from, or creating computing machinery. It includes the study and experimentation of algorithmic processes and development of both computer hardware , hardware and sof ...

METADATA_BLOCK_VORBIS_COMMENT. Other existing and proposed mechanisms are: *

metadata blocks * Ogg Skeleton *

Continuous Media Markup Language Continuous Media Markup Language (CMML) is to audio or video what HTML The HyperText Markup Language, or HTML is the standard markup language #REDIRECT Markup language In computer text processing, a markup language is a system for annotat ...

(deprecated)

History

The Ogg project began with a simple audio compression package as part of a larger project in 1993. The software was originally named ''Squish'' but due to an existing trade mark it was renamed to '' OggSquish''. This name was later used for the whole Ogg project. In 1997, the Xiphophorus OggSquish was described as "an attempt both to create a flexible compressed audio format for modern audio applications as well as to provide the first audio format that is common on any and every modern computer platform". The OggSquish was in 2000 referred to as "a group of several related multimedia and signal processing projects". In 2000, two projects were in active development for planned release: Ogg Vorbis format and libvorbis—the reference implementation of Vorbis. Research also included work on future video and lossless audio coding. In 2001, OggSquish was renamed to ''Ogg'' and it was described as "the umbrella for a group of several related multimedia and signal processing projects". Ogg has come to stand for the

file format A file format is a standard Standard may refer to: Flags * Colours, standards and guidons * Standard (flag), a type of flag used for personal identification Norm, convention or requirement * Standard (metrology), an object that bears ...

, as part of the larger Xiph.org multimedia project. Squish became just the name of one of the Ogg codecs. In 2009, Ogg is described as "a multimedia container format, and the native file and stream format for the Xiph.org multimedia codecs". The Ogg reference implementation was separated from Vorbis on September 2, 2000. In May 2003, two Internet RFCs were published relating to the format. The Ogg bitstream was defined in (which is classified as 'informative') and its Internet content type (application/ogg) in (which is, , a proposed standard protocol). In September 2008, RFC 3534 was obsoleted by , which added content types video/ogg, audio/ogg and filename extensions .ogx, .ogv, .oga, .spx.

OGM

In 2002, the lack of formal video support in Ogg resulted in the development of the ''OGM'' file format, a hack on Ogg that allowed embedding of video from the Microsoft

DirectShow DirectShow (sometimes abbreviated as DS or DShow), codename Quartz, is a multimedia framework A multimedia framework is a software framework that handles Electronic media, media on a computer and through a network. A good multimedia framework off ...

framework into an Ogg-based wrapper. OGM was initially supported only by closed source Windows-only tools, but the codebase was subsequently opened. Later, video (and subtitle) support were formally specified for Ogg but in a manner incompatible with OGM. Independently, the

Matroska The Matroska Multimedia Container is a free and open container format, a file format A file format is a standard Standard may refer to: Flags * Colours, standards and guidons * Standard (flag), a type of flag used for personal ident ...

container format reached maturity and provided an alternative for people interested in combining Vorbis audio and arbitrary video codecs. As a result, OGM is no longer supported or developed and is formally discouraged by Xiph.org. Today, video in Ogg is found with the .ogv file extension, which is formally specified and officially supported. Software and codecs that support .ogm files are available without charge.

2006

Although Ogg had not reached anywhere near the ubiquity of the

MPEG The Moving Picture Experts Group (MPEG) is an alliance of working groups established jointly by International Organization for Standardization, ISO and International Electrotechnical Commission, IEC that sets standards for media coding, includ ...

MPEG

standards (e.g.,

MP3 MP3 (formally MPEG-1 Audio Layer III or MPEG-2 Audio Layer III) is a coding format for digital audio Digital audio is a representation of sound recorded in, or converted into, Digital signal (signal processing), digital form. In digital a ...

MP3

/ MP4), , it was commonly used to encode

free content Free content, libre content, or free information is any kind of functional work, work of art, or other creative Content (media and publishing), content that meets the definition of a Definition of Free Cultural Works, free cultural work. De ...

(such as free music, multimedia on

Wikimedia Foundation Wikimedia Foundation, Inc. (WMF, or simply Wikimedia) is an American foundation headquartered in San Francisco, California San Francisco (; Spanish language, Spanish for "Francis of Assisi, Saint Francis"), officially the City and ...

projects and

Creative Commons Creative Commons (CC) is an American non-profit organization A nonprofit organization (NPO), also known as a non-business entity, not-for-profit organization, or nonprofit institution, is a legal entity organized and operated for a colle ...

files) and had started to be supported by a significant minority of

digital audio player A portable media player (PMP) or digital audio player (DAP) is a portable consumer electronics Consumer electronics or home electronics are electronic Electronic may refer to: *Electronics Electronics comprises the physics, engineer ...

s. Also supporting the Ogg format were many popular video game engines, including ''

Doom 3 ''Doom 3'' (stylized as ''DOOM³'') is a 2004 survival horror first-person shooter video game developed by id Software and published by Activision. ''Doom 3'' was originally released for Microsoft Windows on August 3, 2004, adapted for Linux lat ...

'', ''

Unreal Tournament 2004 ''Unreal Tournament 2004'' is a first-person shooter, first-person arena shooter video game developed by Epic Games and Digital Extremes. Part of the Unreal (video game series), ''Unreal'' franchise, it is the third game in the ''Unreal Tournamen ...

'', '' Halo: Combat Evolved'', ''

Jets'n'Guns ''Jets'n'Guns'' is a 2004 2D computer graphics, 2D Scrolling shooter, horizontally scrolling shooter for Microsoft Windows by Czech studio Rake in Grass. In April 2006, a version for Mac OS X was released. In December 2006 an expansion, ''Jets'n' ...

'', '' Mafia: The City of Lost Heaven'', '' Myst IV: Revelation'', ''

StepMania ''StepMania'' is a cross-platform Rhythm game, rhythm video game and game engine, engine. It was originally developed as a clone of Konami's arcade game series ''Dance Dance Revolution'', and has since evolved into an extensible rhythm game engi ...

'', '' Serious Sam: The Second Encounter'', ''

Lineage 2 ''Lineage II'' is a massive multiplayer online role-playing game A massively multiplayer online role-playing game (MMORPG) is a video game that combines aspects of a role-playing video game and a massively multiplayer online game. As in role-p ...

'', ''

Vendetta Online ''Vendetta Online'' is a twitch-based, science fiction Science fiction (sometimes shortened to sci-fi or SF) is a genre of speculative fiction which typically deals with imagination, imaginative and futuristic concepts such as advanced sci ...

'', ''

Battlefield 2 ''Battlefield 2'' is a 2005 first-person shooter Military Simulation, military simulator video game, developed by EA DICE, Digital Illusions CE and published by Electronic Arts for Microsoft Windows as the third game in the Battlefield (video ga ...

'', and the ''

Grand Theft Auto ''Grand Theft Auto'' (''GTA'') is a series of action-adventure games created by David Jones and Mike Dailly (game designer), Mike Dailly. Later titles were developed under the oversight of brothers Dan Houser, Dan and Sam Houser, Leslie Benz ...

'' engines, as well as the audio files of the

Java Java ( id, Jawa, ; jv, ꦗꦮ; su, ) is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea to the north. With a population of 147.7 million people, Java is the world's List of ...

-based game, ''

Minecraft ''Minecraft'' is a sandbox video game A sandbox game is a video game A video game is an electronic game that involves interaction with a user interface or input device such as a joystick, game controller, controller, computer keyboard, ...

''. The more popular Vorbis codec had built-in support on many software players, and extensions were available for nearly all the rest.

2007

On May 16, 2007, the

Free Software Foundation The Free Software Foundation (FSF) is a 501(c)(3) A 501(c)(3) organization is a corporation, trust, unincorporated association, or other type of organization exempt from federal income tax under section 501(c)(3) of Title 26 of the United States ...

started a campaign to increase the use of Vorbis "as an ethically, legally and technically superior audio alternative to the proprietary MP3 format". People were also encouraged to support the campaign by adding a web button to their

website A website (also written as web site) is a collection of web page A web page (or webpage) is a hypertext Hypertext is text displayed on a or other with references () to other text that the reader can immediately access. Hyperte ...

website

blog A blog (a truncation In mathematics and computer science, truncation is limiting the number of numerical digit, digits right of the decimal point. Truncation and floor function Truncation of positive real numbers can be done using the f ...

. For those who did not want to download and use the FSF's suggested Ogg player ( VLC), the Xiph.Org Foundation had an official codec for

QuickTime QuickTime is an extensible multimedia framework A multimedia framework is a software framework that handles Electronic media, media on a computer and through a network. A good multimedia framework offers an intuitive Application programming ...

-based applications in

Windows Microsoft Windows, commonly referred to as Windows, is a group of several proprietary {{Short pages monitor