Ogg

Ogg is the umbrella for a group of several related multimedia and signal processing projects that are open source and royalty free. Development of these projects is controlled by Xiph.org.

Ogg Vorbis

Ogg Vorbis a fairly new audio Compression format brought together by Xiph.org, the creator of the Ogg Container.

It is similar to MP3, VQF, AAC, and other digital audio formats but with many advantages. It is an open source, free and unpatented format meaning anyone can use it, and the format promises better quality sound in smaller file sizes.

OGG audio is often found accompanying XviD etc. video content in an OGM container, and is abundant on the Internet for decent quality audio recordings, usually from CDs. Vorbis is a lossy compression, meaning that audio data is physically removed from the stream and cannot be recovered afterwards, the same type of compression used by MP3.

Ogg Tarkin

Ogg Tarkin is a video codec currently under development by Xiph.org Foundation and it is part of the Ogg umbrella group of multimedia products. Tarkin is about to be released in summer 2003 or nearby. Other products in Ogg family include audio codec Ogg Vorbis and Ogg Theora.

Ogg Media

Ogg Media (OGM) is a video, audio and subtitle stream Container format. It was developed by Tobias Waldvogel and has features that common AVI formats cannot do. These features in particular include

Chapter Support
Multiple subtitle tracks
Multiple audio tracks of various formats including MP3, AC3, AAC, Vorbis and LPCM)
Vorbis audio support as there is no correct way for AVI to support Vorbis

OGM support for Windows comes by way of the creator's own OggDS or Direct Show Filter, Haali Media Splitter, VLC or RadLight's Ogg Media filter. Most of these filters plug-in to Windows Media Player and allow for changing subtitle preferences (possibly between Japanese and American subtitles are one example), changing audio preferences (changing between the native language of an audio stream to an embeded dubbed language) or even simply fast forwarding to a particular part of the video stream much as you would a DVD player. On Unix based machines, OGM support is available through MPlayer, xine and VLC.

Originally, the OGM format was developed as a hack to the Ogg container and some say will only be a temporary solution to replacing Ogg as more mature and feature rich formats are taking preference amongst downloaders. Formats such as Matroska are getting the nod towards wider range of support. The one major drawback of OGM initially was that it was not a free software, even though it was based on the open-source project for Ogg framework. Later, the creator joined the Ogg development team and donated all his code to the Xiph.org people.

Typically and most often, OGM contained files carry video encoded in the MPEG-4 ASP format and audio in Vorbis or AC-3.

Relevant Guides

How to play OGG files- This guide shows methods to play OGG audio files (with a .ogg extension) in a variety of media players, including adding support to Windows Media Player (WMP) and other DirectShow-based players. It also shows how to add support for informative tags embedded in some OGG container files.

How to play OGM files- An OGM file is an OGG media file. OGM is a container format that can store video streams, audio streams and subtitles. This article shows how to play OGM files and use some of its advantages over the AVI container.