Hi, I would like to ask about the laws we have to obey when we film ourselves performing on the streets. If we want to use the footage on youtube, what should we tell them and have them agree to it so we have full rights of the footage? and if we want to use the footage for commercial use(for instance, feature it inside a magic dvd), we do we need to have them agree to? Thanks for the help.
p.s. I know the laws differ from country to country, but a general idea will be fine.

Tje laws really differ from country to country and in the USA from state to state. Where are you

Usually if you film in a public place you don't need permission, I would still ask people before recording them, just to be polite.

I'm currently filming in Melbourne, Australia. Does anyone know about the laws here? Or can anyone elaborate more on the laws of a particular country or state you are in, I know it can be different but I can still kind of get the idea. Thanks.

Ebackes88 is right as far as the state's go. As long as you are in public your pretty good

It can never hurt to have them sign a waiver release to be filmed. You can find video releases doing a simple search on Google. With this type of written, signed contract you are most definitely safe using your video. And yes. Always do ask before filming.

Definitely ask. Waivers are the safest bet. If you can, at least get them to say on camera that they're okay with the videotaping. You don't need to use that footage, but just have it in case you need it.

It also depends on what you will do with video...if you use it on youtube you might be ok,ask to spectators just to be polite...it's like an editorial.Instead if you use your video for selling a product,a dvd or also your image it's better to fill a model release,you can find ready to use form on internet, like the ones used for commercial photography and videography.
I'm a stock photographer,so I know what I'm talking about. If you use your video for commercial purposes you have ABSOLUTELY to fill a model release.Doesn't matter if you are in public or studio.Doesn't matter if they say ok, words have no legal value.You can use something like that: http://www.creativephotobook.co.uk/ModelReleaseForm.pdf. And also you need a property release if you are shooting in a private property.

Great info, fabio.
I usually only ask them to say on camera they consented for this footage to be release to the public.
But if its for commercial purpose its best to have a Waiver to safeguard yourself.