libvpx-vp9 and the Alliance for Open Media

This article explores the historical and technological relationship between the libvpx-vp9 video codec library and the Alliance for Open Media (AOMedia). It outlines how Google’s development of the VP9 video format served as the direct foundation for AOMedia’s royalty-free AV1 codec, and how the two entities are linked through shared industry goals and technological lineage.

What is libvpx-vp9?

libvpx is a free software video codec library from the WebM Project, which is sponsored by Google. Specifically, libvpx-vp9 is the software encoder and decoder implementation for the VP9 video coding format. Released in 2013, VP9 was designed to succeed VP8 and compete directly with the proprietary H.264 and HEVC (H.265) standards, offering high-quality video compression suitable for HD and 4K streaming without licensing fees.

What is the Alliance for Open Media (AOMedia)?

The Alliance for Open Media (AOMedia) is a non-profit consortium founded in 2015 by a group of leading technology companies, including Google, Mozilla, Cisco, Microsoft, Netflix, Amazon, and Intel. The primary goal of AOMedia was to define and develop next-generation, open, royalty-free video codecs to replace expensive proprietary alternatives.

The Core Relationship: Lineage and Evolution

The relationship between libvpx-vp9 and AOMedia is one of direct evolutionary inheritance. VP9 is the technological parent of AV1, the flagship video codec developed by AOMedia.

1. From VP10 to AV1

Before the formation of AOMedia, Google was actively developing VP10 as the successor to VP9, and the work was being integrated into the libvpx codebase. When AOMedia was founded in 2015, Google contributed its VP10 technology to the alliance. AOMedia combined Google’s VP10 with Cisco’s Thor codec and Mozilla’s Daala codec to create a new, unified standard: AV1 (AOMedia Video 1).

2. Foundational Code and Architecture

Because AV1 evolved heavily from VP10 (which was the direct upgrade path from VP9), much of the underlying architecture of AV1 resembles VP9. The reference software library for AV1, known as libaom, was built using the libvpx codebase as its starting point. Developers familiar with the structure and optimization techniques of libvpx-vp9 will find a highly similar architectural layout in libaom.

3. Shift in Stewardship

The transition from VP9 to AOMedia’s AV1 represents a shift in industry stewardship. While VP9 and the libvpx library were primarily driven and controlled by Google under the WebM umbrella, AV1 is governed by the broader, multi-company consensus of AOMedia. This collaborative model helped AV1 gain wider and faster industry adoption across hardware manufacturers, browser developers, and content distributors than VP9 initially did.

In summary, libvpx-vp9 represents the pinnacle of Google’s independent royalty-free video efforts, which ultimately served as the primary technological and organizational catalyst for the creation of the Alliance for Open Media and its AV1 codec.