Nice try, hope the frame didn't get hurt.
Sometimes people take up their cellphones when I ride. One time when I only had been riding trials for ½ year a bunch of kids came up to me and asked the 100 usual questions, no filming that time but they wanted to shake my hand if I some day would be big and famous like Danny Macaskill.
Most people is a bit afraid to film someone just like that and may not dare to ask if it's OK. I've seen a few kids that have taken up their phones to try to capture some jumps in secret.