I have many video codecs installed on my machine but Virtualdub only lets me choose from a very basic selection.
Do I have to manually point VirtualDub to the codecs somehow?
VirtualDub requires a Video for Windows (Vfw) compatible codec to decompress video.
DirectShow codecs such as those used by Windows Media Player, are not suitable.
This means that not all the codecs installed on your computer can be used by VirtualDub.
A very good codecs package that has VFW is ffdshow.
Just ensure you enable all your format decoders under VFW Configuration -> Decoder -> Codecs.
How do I manually add/remove/switch codecs?
In Windows NT/2000, these settings are stored in the Registry, with the VIDC.xxxx part as the key and the driver name as the value. Most codecs are stored in:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Drivers32
You may also find them in a subkey under:
HKEY_CURRENT_USER\Software\Microsoft\Multimedia
Usually, after a change you only need to restart applications that use codecs, rather than having to restart the entire system.
Source and more information regarding VirtualDub and codecs.
No, but you should use the 32-bit version of Virtualdub since most codecs out there aren't recompiled for the 64-bit version.