USB frame grabber

hi to all!!!!!!!!! can you please suggest me some video processors that i want to include in my design of USB frame grabber.let me be more clear.i am under process of designing of one frame grabber board which will receive input from USB cameras via USB 1.1 port and wil pass the frames to the PC via another USB port.so for this purpose do i need any video processor in my design or as i am receiving the data from USB camera, i just need to send this data to USB port of PC ,no need of any video processor? please suggest me. with regards