is this illegal?

Is it illegal to take videos of pictures of someone in public and post it on Facebook? This guy I know posted a video of a girl in a drive through at McDonalds and then trashed her for not responding the way he wanted. He was attempting to scare her by pulling up to the drive thru in a mask and it pissed her off. Doesn't even know her, she doesn't even know she's on the internet being trashed. It reallly pisses me off.