VirtualDub is an open source video capture and linear processing tool for Microsoft Windows. It is written by Avery Lee , and is licensed under the GPL. It is hosted on SourceForge and is at version 1.5.10 (stable) and 1.6.5.23350 (experimental).

It features many advanced features as well as being able to use plugins to add different video processing techniques, and can process AVI files, regardless of the codec as long as the video and audio codecs are installed.

Early versions of VirtualDub supported importing of Microsoft's ASF file format but due to a software patent issue this was removed in version 1.3d onwards.

The story is that Microsoft seems to want to have control over the accessablitly of the content by forcing Free Software to not read ASF files directly, gaining Mircosoft complete control over the means of reading ASF files, despite having done a completely legal reverse-engineering of the file format.

VirtualDub cites US Patent 6,041,345 as one of possible guns behind the letter from Microsoft but there may be many more patents, nobody knows and it's impossible to know for sure. In future versions, Avery has promised "legal" ASF support through the use of DirectShow Filters.

A spin off project VirtualDubMod was started to include extra features not in Avery Lee's version - such as support for MPEG-2 and Ogg Theora.

See also

• List of video editing software
• Comparison of video editing software

External links

• Official Homepage
• Why Avery wrote VirtualDub
• SourceForge Project Page
• Forums
• Microsoft's ASF patent notice (detailed discussion linked from there too)