is a video codec
created by Happy Machines (3ivx.com
It has been created to allow MPEG-4 compression on .mov file types. Previously MPEG-4 compression was only possible on .asf files through Microsoft's codec and for .avi files through the DivX codec.
A notable feature of 3ivx is that it allows for streaming of 3ivx files over the Internet, a feature not possible through the .avi filetype.