You are allowed to take photographs / video shooting everywhere, except tourist attractions where a nominal charge is levied eg. USD 1-3. In these places, they also have professional photographers who would take group or solo photographs for a nominal fee. Photography is strictly prohibited in the Underground Metros for security purposes, and there are local police at every metro station. It is at their discretion, where they can either give you a warning first or simply confiscate your camera or cell phone. If you wish to take photographs of the local people, it is normally advised to request them beforehand.