In reply to m0unt41n: Short answer... They are taking images (moving or still) openly, in the UK no permission is required in public, as there is no reasonable expectation of privacy in a public place. However, landowners may have their own rules if you are on private property.
If you feel uncomfortable with being recorded, you can speak up and ask that they stop or not record you. If they do not respect your wishes, also depending on the manner in which you are being photographed/recorded, it may then become harassment, which is an offence.
No permission is required to upload the captured footage, which is the property of the photographer. If the footage was taken under protest, or depending on how it's cut, then this upload could also constitute harassment.
All photographers I know would honour the wishes of anyone who speaks up and wishes to be excluded from being filmed/photographed, no questions asked.
I'm not sure if this differs if you are being filmed/photographed covertly (just google "Spy Camera"), but that it far more sinister and a lot more difficult to spot.