there seem to be a reasonable selection of ITX boards that work fine as media directors..
the core however (from what I have seen) should be something more substantial

especially runnung multiple 720p streams!
also you will want to have quite a lot of storage at the core!
I see Brazil is quite strange about its TV standards as you say

maybe satellite capture may be easier ?
but anyway..
the cor..
make it as powerful and big as is reasonable

if you don't you (like me) will just end up building another core when you run out of slots / drive bays
