Here is the page you can download WebM video audio codec
WEBM – a better video format based on HTML5 developed by Google.
Download WebM codec (name: opencodecs_0.85.17777.exe | size: 2.53MB | version: 0.85.17777.0)
What is the WebM video format?
The goal of Google is to build an open, royalty-free video file format. The video file format should be able to provide high-quality video compression used with HTML 5. WebM project is an open source project uses the BSD license, which uses VP8 video codec developed On2 Technologies and Vorbis audio codec developed Xiph.Org Foundation (an open source and patent-free audio compression limit format), which uses the package format places Matroska (MKV) format based on open source.
Relative to the current VC-1, H.264 and other video compression formats, WebM VP8 has obvious technical upgrading of technology through continuous optimization of Google, which added more than 40 innovative technologies, decoding speed, compression efficiency and performance are significantly enhanced, making WebM VP8 bitstream decoding requires only minimal processing cycles, thus with less data able to provide higher-quality video, users do not have high-end PC or mobile device can also enjoy WebM VP8 video quality.
Currently, Google Chrome, Microsoft IE9, Mozilla Firefox, Opera, Apple Safari and other major high-profile mainstream browsers support the HTML 5 standard, and WebM VP8 as an important component of the project HTML 5 standards is also actively supported by other forty WebM publishers and computer hardware and software suppliers (including AMD, NVIDIA, etc.)