VirtualDub

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 GNU General Public License. It is hosted on SourceForge.

=About VirtualDub=

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.

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.

==Filters==

VirtualDub comes with a number of filters. Examples include reducing the video size by half, converting the video to grayscale, and about a dozen more.

==Modifying a video==

In addition to filters, you can save the entire image sequence onto your hard disk as Windows bitmap or truevision TGA files. From there, you can modify the images and later add your modifications. Also you can extract the sound track of a video, and make modifications. You can then apply filters and make modifications to sound track and reapply them to the video. You can even replace an existing sound track or video or add a sound track or more frames to your own creations. Frame sequences and sound tracks must be editted in external software programs.

==Creating a video==

VirtualDub can also be used to create a video file from a series of bitmaps or targas. Individual frames are created in an external graphics program like Paintshop Pro, Photoshop, or the GIMP. The images must be in sequential order like 001.bmp, 002.bmp, 003.bmp and so on without any jumps. From those, you can adjust the frame rate, add a sound track and make other modifications.

=External links=

*[http://www.virtualdub.org/ Official Homepage] *[http://www.virtualdub.org/virtualdub_history Why Avery wrote VirtualDub] *[http://sourceforge.net/projects/virtualdub SourceForge Project Page] *[http://forums.virtualdub.org Forums] *[http://swpat.ffii.org/patents/effects/asf/ Microsoft s ASF patent notice] (detailed discussion linked from there too) *[http://www.advogato.org/article/101.html Microsoft patents ASF media file format, stops reverse engineering]