6. Capturing with VirtualDub or VirtualVCR

6.1 Capturing with VfW or WDM drivers

"I see that there are a lot of capturing programs (like: VirtualVCR, iuVCR, Virtualdub, VirtualdubMod, AVIO, FLYDS and more), which one should I use?"

In principle you could try all of them, but there are some catches. There exists two device driver models: VfW (Video for Windows) and WDM (Windows Driver Model). The capture programs VirtualVCR, iuVCR and FLYDS support WDM, and Virtualdub, VirtualdubMod and AVIO support VfW. But a capture driver is based on one of those device driver models. In principle you should stick to the following:

If your capture driver supports VfW, use a VfW capture program like: Virtualdub, VirtualdubMod or AVIO.
If your capture driver supports WDM, use a WDM capture program like: VirtualVCR and iuVCR.

In this guide it will be shown how to capture with two capture programs: Virtualdub (which supports VfW) and VirtualVCR (which supports WDM). Below is some more information about VfW and WDM. If this is to technical for you, just proceed with the next subsection.

Some general information about VfW and WDM:

VfW is old (and not being developed any more) and because of its limitations, Microsoft has come up with a new device driver model: WDM (supported natively starting from Windows 2000).
Most video capture drivers are now being developed using WDM.
There is a VfWWDM wrapper which enables you to capture in Virtualdub (or other VfW based capture programs) using WDM drivers. But you need a fast processor when using this wrapper, since it produces a high CPU load.
VfW will continue to be supported in Windows 98, Windows 2000, Windows NT and Windows XP, but most of the times the card driver is the problem. Newer cards simply don't have VfW drivers, and only Hauppauge has VfW drivers for W2K and XP.
VfW has no TvTuner support, while WDM has.
If you installed DirectX 9.0b (and have PAL and W2K/XP), make sure you also install the patch! The problem is that your TV input stops working, have a look at this thread.
You can face different kind of problems: can't capture with WDM based capture programs keeping video and audio sync., can't capture at full size using the VfWWDM wrapper, etc. If you have similar problems, don't hesitate to ask for help in the Capturing video forum at doom9!

Some bt8x8 driver information:

WDM drivers for bt8x8 chips: btwincap (you could have some troubles with installation and usage, sound appears to be mono; btwincap is fully compatible with the wrapper, so you can use btwincap-VirtualDub combo) or iulab tweaked wdm driver (cannot be used with VirtualDub, because it's not compatible with the wrapper).

Some Hauppauge driver information:

WDM and VfW drivers which are supposed to work under Windows 98, Windows 2000, Windows NT and Windows XP (but they don't let you capture at full size though).

References:
WDM Video Capture Overview: General VfW and WDM information, states also the advantages of WDM.
Capture using Video for Windows: The timeline of VfW and WDM.
Video Capture: More general info about VfW and WDM.
VfWWDM wrapper: The download link can be found in question 14.
DirectX 9.0b patch: Non-NTSC TV Tuner Hotfix for DirectX 9.0b
An interesting Doom9 thread about the history of vfw and wdm.

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Last edited on: 06/13/2004 | First release: n/a | Author: Version4Team | Content by Doom9.org