I'm not sure what it contains, but while you would be the copyright holder and have the rights to this footage, you need to be concerned that by commercializing the image or likeness of someone else may expose you to claims that you violated the subject(s) rights of privacy and publicity. These are state law claims and the statutes vary regards to whom may have a cause of action (only celebs, any live person, even dead people up to 10 years, etc.).
Merely posting the video in social media platforms does not concern me, but monetizing and commercializing it may be an issue. I suggest that you reach out to a lawyer in private for a proper opinion before you jump in and do that.
DISCLAIMER: this is not intended to be specific legal advice and should not be relied upon as such. No attorney-client relationship is formed with the law firm of Natoli-Lapin, LLC on the basis of this posting.
Wrong question. Sure you can, but your question is, "is it legal" and "what's my risk". We seldom go to links Askers give - too many scams exist for than - but I assume there are people other than you in the video. You may need permission if the people are other than just incidental in the background. By being in a street festival, people implicitly must expect to be smartphone videoed in the background. Heck, they are probably in a dozen security camera videos, too. Most people just monetize and address any complaints when, and if, they arise. If someone really objects, they will most likely just send YouTube a DMCA takedown notice and your video will get yanked unless you do a counternotice.
I am not your lawyer and you are not my client. Free advice here is without recourse and any reliance thereupon is at your sole risk. This is done without compensation as a free public service. I am licensed in IL, MO, TX and I am a Reg. Pat. Atty. so advice in any other jurisdiction is strictly general advice and should be confirmed with an attorney licensed in that jurisdiction.
This depends on what is in the video. If there is music in the video, you cannot legally post it without a synchronization license from owners of the copyright in the composition and master recording (if a recording is used from a record). If there are performers, dancers, musicians or models in the video, you probably need their permission before posting the video on You Tube because otherwise you are violating their rights of publicity and potentially their copyrights in their performances. If your film caught someone in an embarrassing situation of some kind, your video could violate rights of privacy. It is possible that you would have a defense to allegations of infringement based on application of the "fair use" doctrine---if your film was posted for purposes of journalism of social, political or academic commentary, you might be protected by the fair use doctrine (which incorporates First Amendment protections into IP law). But if your main purpose for posting the film is commercial, the fair use doctrine probably won't help.
While you own the copyright in the film itself, others may own copyrights in elements of the film, such as music or trademarks (brand names) that may appear in it. You certainly could face DMCA takedown notices, which You Tube would honor until you objected to the take-down. Your bigger problem is that if the video proves successful or goes viral, enterprising lawyers will smell money and may decide to pursue copyright claims against you on a contingency fee basis. Even if the claim relates only to music that appears in the video, you could face exposure of up to $150,000 for each musical composition at issue because your infringement would almost certainly be deemed willful.
The bottom line is this---you should retain and consult with legal counsel concerning this video before doing anything further with it. And if you are exposed to claims for copyright infringement or other IP law violations, you would be wise to voluntarily take down the video. If you want to "monetize" the video, then retain counsel to get the licenses that you need for the music, performers, brand names and other elements that appear in it that may be protected by IP law. You may be able to profit from this but you will have to share the wealth with the owners of IP rights that you use in the video.