Vorbis Is a free, lossy audio compression format officially released in the summer of 2002. In terms of functionality and quality, it is similar to such codecs as AAC, AC3 and VQF. The psychoacoustic model used in Vorbis is similar in principle to MP3 and the like, however, the mathematical processing and practical implementation of this model are significantly different, which allowed the authors to declare their format completely independent of all predecessors.

Container

The Ogg media container is most commonly used for storing Vorbis audio data, this file usually has the .ogg extension and is called the double name „Ogg / Vorbis" or „Ogg Vorbis". However, „Ogg Vorbis" is also called the codec itself without a container, as it is part of the Ogg project.

Application

In 2013, it is much less widespread than MP3. Used in computer games, for podcasts.

Vorbis is ideal for use as movie soundtracks, since it does not change their length at variable bit rates, which allows you to maintain synchronization with the video track, and is applicable for multi-channel audio (for example, 6-channel audio).

It is used for the audio track of files in WebM format together with the VP8 video codec (since VP9, __support for the new free Opus codec has been added to the format).

Metadata

The format was originally designed with streaming capabilities. This gives the format a rather useful side effect – several songs can be stored in one file with their own tags. When loading such a file into the player, all the songs should be displayed as if they were loaded from several different files.

The format has a flexible labeling system. The tag header is easily expandable to include lyrics of any length and complexity (such as song lyrics) interspersed with images (such as album cover photos). Text labels are stored in UTF-8, which allows you to write in multiple languages __at the same time and eliminates possible encoding problems.

Bitrate

Ogg Vorbis uses a variable bitrate by default, while the values __of the latter are not limited to any hard values, and it can vary even by 1 kbps. It should be noted that the maximum bitrate is not strictly limited by the format, and with the maximum encoding settings, it can vary from 500 to 1000 kbps. The sampling rate has the same flexibility – users are given any choice between 2 kHz and 192 kHz.

Purpose of development

Vorbis was developed by the Xiph.Org community to replace all paid proprietary audio formats. Despite being the youngest format of all MP3 competitors, Ogg Vorbis has full support on all popular platforms (Microsoft Windows, Linux, Apple Mac OS, Android, PocketPC, Palm, Symbian, DOS, FreeBSD, BeOS, etc.) as well as a large number of hardware implementations.

Ogg Project

Vorbis is part of the Ogg multimedia project, which also includes free encoders: Speex – for voice compression; FLAC – for lossless audio compression; Theora – for video compression.

Vorbis uses the Ogg container format to store sound.

Vorbis advantages


No patent restrictions.

Up to 255 channels.

Sample accurate – sound data will not have any displacements, extra or lost samples relative to each other.

„Streamable" – support for streaming playback.

Efficient variable bitrate algorithms.

Sampling rates up to 192 kHz.

Bit depth up to 32 bits.

Flexible Joint stereo.

Flexible psychoacoustic model.

Labels are stored in Unicode, not national encoding.

Higher compression ratio compared to MP3 at equal quality (smaller file size)


Implementation

Due to the open development and distribution model, there are several variants of Vorbis software encoders and decoders.

Official programs and libraries

Officially implemented by the developers of the Ogg and Vorbis standards, the Xiph.Org Foundation, is distributed under the BSD and GNU LGPL type licenses.

The official encoder program is the free oggdropXPd, which exists in different versions: libVorbis or aoTuVb libraries are used, and optimization for different processors. The latest version of libVorbis 1.3.7 was released on July 6, 2020.

aoTuV

Version from Japanese developer Aoyumi. Thanks to the improved psychoacoustic model, a significantly higher sound quality is achieved, while aoTuV does not violate compatibility with the official standard. Although Aoyumi is not an official developer of the Vorbis codec, his merits were so high that the code he developed (beta 2) was added to the official libraries of version 1.1.0 on September 22, 2004. The latest version is Beta 6.03 dated April 25, 2011. However, the aoTuV code was used in official and third-party implementations of subsequent versions of the encoder.

Lancer

Japanese developer Nyaochi is working on increasing the Vorbis encoding speed. Its version, called Lancer, is based on current versions of aoTuV. Thanks to optimizations of the code for modern processors, a significant increase in the speed of encoding and decoding is achieved (by tens of percent, in some conditions several times). At the same time, the quality suffers very slightly. Its latest development is dated November 10, 2006. The Nyaochi code has also been used in third-party implementations of subsequent versions of the encoder.

Tremor

A fixed point implementation of the Ogg Vorbis decoder designed for platforms that do not support floating point numbers.

The future of the codec

The developer of the Ogg project, the Xiph.Org Foundation, recommends using the new royalty-free Opus codec instead of Vorbis.