Time Stamp Format

[linuxline]

Hi, which format are the time stamps shown? Are they UTC, GMT, etc? Just wanted to verify the date and time shown and if I need to convert to know the true date and time.

Thank you!

[StarGeek]

It all depends upon the setting of the camera that took the image.  If the time wasn't properly set, then it could be anything.

According to the specs, still images are supposed to be set to the local time of where the image was taken.  Videos are supposed to be set to UTC.  But in the case of cameras, people sometimes don't bother to set the time or don't make adjustments when they go on vacation to another time zone.  For videos, if the camera wasn't part of a phone, then the camera has no way of knowing the time zone unless there's an option to set it.  Those cameras would have to set the time stamp according to the only time they would know.

Then there are a few people who travel a lot who just set the camera to UTC so as not to have to bother with setting the camera to the local time.

And then, of course, there are programs like exiftool which can alter the time stamps to any time/date.

Exiftool just displays the time as it is set in the file.  There's no real way to guarantee what the "true" date and time is when the image/video was taken.

[linuxline]

Thank you!

So ExifTool does not standardize timestamps to any particular time zone...that is good to know.

[StarGeek]

That's correct, exiftool just lists the data that's in the file.

In the case of video files there is the -api QuicktimeUTC option that will convert the time stamps to local time (see -api QuickTimeUTC option).