pdf converter

[Nicolas Ferr�]

Dear all,
Does it exist a pdf to lyx converter (optionally pdf to latex) ? Actually, 
some pdf to text converters exist, like pstotext.
But I'm wondering if some programs could extract also formats or even tables 
from a pdf file. I must confess I'm not quite sure what type of information 
is stored in a pdf file ! So I hope my question is not too naive !
Nicolas