Low Latency Interlaced Video

[Paul Barber]

Hi,

What is the best way to deal with a truly interlaced video source?

I have written a source plugin for the VRMagic USB frame grabber 
(VRMAVC-2), and for the lowest latency I can configure it to send me 
individual fields at 50 fps (each half-frame height). I would like to 
have a downstream element that will combine these fields (e.g. weave 
them) into a full frame, still at 50 fps. Does such an element or sink 
exist?

Alternatively, I can configure the source to send interlaced frames at 
25 fps, and use the "deinterlace" element to construct full frames at 50 
fps. This looks very nice, but I am hoping to reduce the latency by 
working with fields were possible.

Any ideas?
Cheers,
Paul.