Opus is now RFC6716, version 1.0.1 released! Options

[xiphmont]

"Mozilla and the Xiph.Org Foundation are pleased to announce the Internet Engineering Task Force (IETF) has standardized Opus as RFC 6716. Opus is the first state-of-the-art, fully Free and Open audio codec ratified by a major standards organization."

Full announcement at xiph.org/press/2012/rfc-6716

Yay!

This post has been edited by Frank Bicking: Sep 11 2012, 20:46

Reason for edit: Fixed URL.

[Anakunda]

Here is a new opus library version 1.1 alpha announced:

This is an alpha release for the upcoming 1.1 version. Compared to 1.0.2, it includes quality improvements, optimizations, bug fixes, as well as an experimental speech/music detector for mode decisions. All the fixes and improvements from 1.0.2 are also in this release. Quality improvements include unconstrained VBR, a bitrate boost for tonal frames, and improvements to tf estimation, transient detection and dynamic allocation.

Please give it a try

CODE

http://www54.zippyshare.com/v/27314730/file.html

The question is: what's unconstrained VBR. Is it a way closer to true VBR mode like on other encoders?

This post has been edited by Anakunda: Dec 23 2012, 01:55

[saratoga]

The question is: what's unconstrained VBR. Is it a way closer to true VBR mode like on other encoders?

Its another word for quality based VBR basically.

[Anakunda]

The question is: what's unconstrained VBR. Is it a way closer to true VBR mode like on other encoders?

Its another word for quality based VBR basically.

Yup then now to find a way to control the encoder in this mode. So far I've found only bitrate control since opus-tools 0.1.6 still doesnot support any quality-based parameters.

[Speckmade]

So far I've found only bitrate control since opus-tools 0.1.6 still doesnot support any quality-based parameters.

It does. For short: The bitrate control is quality-based - at least in this mode.
The encoder tries to keep quality constant and varies bitrate - even average bitrates even between files. So a target bitrate ideally corresponds to a fixed level of quality for a given encoder model.
Remember that the quality parameter of other codecs also (at least often?) translates to a target bitrate. The Opus encoder just saves you the hassle of having different control parameters for unconstrained, constrained VBR and CBR modes. It also hinders confusion from people comparing quality levels between different encoders and/or formats, like expecting Vorbis' q1 sounding competitive to Opus q1. Or, OTOH, it saves the work of trying to make it somehow fit in with the quality levels of other encoders and then having to extend the scale of quality levels far into the negative number range.