- This article is about the video codec DivX. For the pay-per-view DVD system, see DIVX.
DivX® is a video codec created at DivXNetworks Inc., known for its ability to compress lengthy video segments into small sizes and has been the center of controversy because of its
use in the replication and distribution of copyrighted DVDs. Many newer DVD players are able
to play DivX movies.
DivX is not to be confused with DIVX, an unrelated attempt at a new DVD rental system employed by the US retailer Circuit City. Early versions of the DivX codec were named "DivX ;-)", where
the winking emoticon was a tongue-in-cheek reference to the failed DIVX system.
A typical feature-length movie on DVD is around 5–6 gigabytes in size;
with DivX this can be compressed to around 700 megabytes which fits on a CD-ROM with minimal loss in quality. Various programs are available which can produce a DivX
file from a normal video DVD (this process is known as "ripping"). The resulting file
can then be stored on hard disk, burned on optical media, or be shared on peer-to-peer
networks.
DivX ;-) 3.11 and earlier versions generally refer to a hacked version of the
Microsoft MPEG-4 Part 2 video codec,
extracted around 1999 by French hacker Jerome Rota (also known as Gej). The
Microsoft codec, originally created for the compression of *.asf files, was altered to allow
compression to *.avi files. From 1998 through 2002, independent enthusiasts within the
DVD-ripping community created software tools that dramatically enhanced the quality of video files that the DivX ;-) 3.11
codec can produce. One notable tool is Nandub, a modification of the open-source VirtualDub, which features two-pass encoding (termed "Smart Bitrate Control or SBC) as well several codec hacks.
Rota's company DivXNetworks, Inc. eventually produced a clean
room version of the codec, thus avoiding potential copyright problems with
Microsoft. This codec was named DivX 4, dropping the smiley. DivXNetworks has applied for a patent for their new codec, which is
fully MPEG-4-Advanced Simple Profile compliant.
Current Situation
The current version of the DivX codec (version 5.2.1) is available through their web site for Windows, Linux, and Macintosh operating systems. It is neither Free Software nor Open Source, but an open source version
of the codec—called OpenDivX®—was released by DivXNetworks in early 2001, and this version served as the basis for
the open source XviD codec, the specification of which is maintained by an independent
group. The codec's main competitors in the for-license video compression software market are Microsoft's Windows Media Video
series, Apple Computer's Quicktime, and the RealNetworks RealVideo series.
External links
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