Directshow - video input card

Hi

i would like to do a project where friend of mine and me will work on the same visual, but how to connect two video outputs from two pc from two different software ?

I was thinking about HW videomix but its NO way expensive, then i have try to send video over network (thanks ft for vlc plugin) but problem is we want to use two projectors 2x 1024 and full hd screen capture over network took lot of performance.
So now i am thinking about HW device (video input) which can be used as an DirectShow video input from other pc

Do you have any experience with video cards for an video input stream? we are using vga so card can be analog.

do you have any recommendation?

thanks

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