"Duclair," the fourth named release of the VP8 Codec SDK (libvpx), is now available. You can download the Duclair libvpx snapshot (version 1.0.0) from our Downloads page or clone it from our Git repository.

This release fixes a decoder crash bug introduced in Cayuga (v0.9.7), so we encourage all Cayuga users to upgrade.

Note that the VP8 format definition has not changed, only the SDK. Duclair is ABI incompatible with prior releases of libvpx, so the major version number has been increased to 1, and you must recompile your applications against the v1.0.0 libvpx headers. The API remains compatible, so code changes shouldn't be required in most applications.

New Features

This release introduces substantial new VP8 encoder features that are especially useful for real-time use cases such as live streaming and videoconferencing.

• Temporal scalability produces a video stream that can be decimated to different frame rates, with independent rate targeting for each substream.
• Multiframe postprocessing can make visual quality more consistent in the presence of frames that are of substantially different quality than the surrounding frames, as in the temporal scalability case and in some forced keyframe scenarios.
• Multiple-resolution encoding enables simultaneous encoding of the same content at different resolutions, resulting in much faster encoding than processing them separately.

Performance Improvements

In this release we focused on optimizing VP8 decoder speed and the real-time modes of the encoder.

• Decoder speed on x86 processors improved 10.5%. 
• Encoder improvements followed a curve where speed settings 1-3 improved 4.0%-1.5%, speeds 4-8 improved <1%, and speeds 9-16 improved 1.5% to 10.5%, respectively.

See the CHANGELOG for a complete description.

Thanks to everyone who worked on Duclair, and welcome to our four new contributors:

• Alpha Lam
• Deb Mukherjee
• Jeff Faust
• Rafaël Carré 

John Luther is Product Manager of the WebM Project.