What is "opencodecs"

OpenCodecs is a software package for enabling HTML5 video on Microsoft Windows, particularly using the Theora and WebM codecs in Internet Explorer. It consists of:

• dshow, Xiph's DirectShow filters for their suite of Ogg formats, including Theora and Vorbis
• webmdshow, the DirectShow filter for WebM maintained by the WebM project
• An ActiveX plugin adding HTML5 video capability to Internet Explorer older than version 9

The DirectShow filters support all DirectShow applications (like Windows Media Player), not just Internet Explorer.