High latency with USB video capture devices

[Donuts]

Host: Xubuntu 9.10 x86. Guest: Windows XP SP3

Hi,

I've been trying to use several USB video capture devices in a Windows XP SP3 guest, e.g. a Pinnacle PCTV USB2 which uses an Empia EM28xx chip.

When used natively in both Linux and Windows, there is very little latency between the input video and what is shown on screen (using e.g. tvtime in Linux or DScaler in Windows). So for example, video games are still very playable.

When used in a VirtualBox guest however, latency is much higher. At least 1-2 seconds, making interactive use with a game console unusable. Is that a defect which could be fixed, or a problem intrinsic to how VirtualBox captures USB devices?

Some other capture devices (e.g. one based on Trident TV Master chip) don't show video at all in the Windows guest; I just got a black window and crackling audio with that. Maybe that's due to the XP driver not working with the increased USB latency?

[aeichner]

Please reopen if still relevant with a recent VirtualBox release.