2022.05.12 19:45 "Re: [Tiff] best tiff tag names for start and end datetimes?", by Bob Friesenhahn

Can you assume DateTime is UTC with your particular files and use cases?

Yes, this is a good fallback option.

I am not sure about established precedence, but this is much better than being a mere fallback option as long as the recipient knows it is UTC. This could be handled via documentation.

Dealing with time zones is hard, and it assumes that both the writer and the reader have knowledge of the current time zone, and access to the time zone database necessary to do conversions.

It may still be necessary for the writer and reader do to something special to produce and consume UTC timestamps.

Unix type systems (and those using NTP) have a system clock which is on UTC time.

Bob

Bob Friesenhahn
bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer, http://www.GraphicsMagick.org/
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