How to Duplicate IMAQ FPGA Pixel Bus

Hello:

I'm new to FPGA Vision, I was trying to compute IMAQ FPGA Centroid, at the same time I want to stream the data to DRAM, also, I want update host image at a lower rate.

I learned the process need to use 4 wire, and seems 4 wire will lock the whole speed of a data stream, I think I need to copy raw Pixel Bus to 2 or even 3 stream, but i didn't found out how to do it, can anyone give me a hint? Thanks a lot!