Security is more important than privacy.
Security staff often do videography of passengers travelling in train. It helps them a lot in maintaining peace and security. 
Passengers cooperate and allow them to be videographed.
But suppose if a passenger refuses to be videographed? Suppose if a passenger asserts his right to privacy? 
In that case, as per my view videography cannot be enforced on a passenger. 
Videography violates individual's  right to privacy. This right can be taken away only if some law is passed. 
At present I do not see such law. But it is also good if passengers cooperate for security reasons. 
Haresh Raichura
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