nuber of FBOs

Dear there!

I have a very big image ( about 80005000 ), in order to improve performance, I had it divided into small segments( like 512512, every piece is an object )when rendering.

Now,I want to do some PingPong smoothing to it. the question is:
can I allocate one FBO per segment? what is the limit of number of FBOs?
or, if I have all the segments share one static FBO, can I render the whole image correctly?