What is Vorbis?
Vorbis is an open, lossy, transform-based audio codec created by Xiph.Org. It is most commonly encountered as Vorbis audio inside an Ogg container.
Technical characteristics
| Property | Vorbis I |
|---|---|
| Compression | Lossy perceptual audio |
| Sample-rate intent | Designed to scale from low-rate speech/telephony through high-rate audio; the specification discusses roughly 8 kHz to 192 kHz use |
| Channels | From mono/stereo and surround layouts up to 255 discrete channels in the bitstream model |
| Bitrate behaviour | Native free-form VBR; bitrate header values can be hints rather than hard limits |
| Transform | MDCT-based transform coding |
Vorbis quality settings
Vorbis encoders are commonly driven by a quality scale instead of an exact bitrate target. The resulting average bitrate depends on the content and encoder. This is a good example of why “bitrate = quality” is too simple.
Vorbis does not require Ogg in theory
The Vorbis specification defines codec packets separately from transport. Ogg is the standard file pairing, while RTP and other transports can also carry Vorbis.
Where Vorbis fits today
Vorbis remains important in existing Ogg and WebM media and in software/game assets. Opus is often preferred for new general-purpose internet audio because it covers speech, music and low latency more efficiently, but Vorbis has a large installed base.