I am not sure of the legalities but I think they operate on an opt out principle, the signs around SYD seem to indicate that is the situation with border security, I cannot imagine all those people caught by customs are "opting in" so to speak to have their faces shown on TV after being caught! I would have thought we would see more shots with smokey obscured faces otherwise.
Good point. I wouldn't be surprised if they did sign something for being the 'focus' though as they do use names, and background stories (like the people going to CBR to see the "DAY GAR" exhibition ).
I do recall the signs around MEL Int terminal about border security being filmed several times whilst passing through there. I never actually saw them filming though.
Now you've got my interest i'd like to know if the announcement is blanket enough