Hi, can someone explain the difference between these fields?
Which one are considered the time of the creation of the .mp4 file?
Why would quicktime Create Date differ from ie Track create date?
exiftool -time:all -a -G1 "1.mp4"
[System] File Modification Date/Time : 2021:01:27 13:25:12+01:00
[System] File Access Date/Time : 2023:05:08 16:13:00+02:00
[System] File Creation Date/Time : 2021:01:27 13:25:13+01:00
[QuickTime] Create Date : 2019:02:03 12:30:03
[QuickTime] Modify Date : 2021:01:27 12:25:03
[Track1] Track Create Date : 2021:01:27 12:23:24
[Track1] Track Modify Date : 2021:01:27 12:23:24
[Track1] Media Create Date : 2021:01:27 12:23:24
[Track1] Media Modify Date : 2021:01:27 12:23:24
[Track2] Track Create Date : 2021:01:27 12:23:24
[Track2] Track Modify Date : 2021:01:27 12:23:24
[Track2] Media Create Date : 2021:01:27 12:23:24
[Track2] Media Modify Date : 2021:01:27 12:23:24
[Microsoft] Encoding Time : 2019:02:03 13:30:03+01:00
The first three are the operating system time stamps for those files. They will be the times that the file was created/modified on that drive. I believe if you're copying directly from one drive to another, they would remain the same most of the time but they will be different if the file is from another source such as downloading from a website.
In theory, the Quicktime:CreateDate would be the time stamp for when the file was created. Quicktime:ModifyDate would be the time when the file was last edited. The Media/Track tags have to do with when the individual tracks where created/modified. For example, if you were creating a video from multiple sources at different times, then these would match the times those tracks were created/modified.
But, as I said, this is in theory. I don't believe there is a set standard for these time stamps, though I could be wrong. At least I haven't seen one. And a lot of programs don't even write these tags. Basically, you can't really rely on them much.
But in this case, because of the Microsoft tag, I would guess that it and the Quicktime:CreateDate are the correct times. The Quicktime:CreateDate is set to UTC, so it is technically 2019:02:03 12:30:03+00:00, which is the same as 2019:02:03 13:30:03+01:00
Thank you! That it very helpful.
What can cause the Quicktime:ModifyDate to differ from all the track modify dates?
And what does the Microsoft tag entail? I can't find any good sources on what this tag actually is.
To be honest, some of this is just guesses based upon how the tags are used in other standards. As for differences time stamps, think of it like this.
You go out and record a video. The track times will be the same. But you're making a music video, so you're only using the video track, not the audio. You record the audio somewhere else.
At this point, the create and modify time stamps are the same in each track, but differ between track. Now, you add some CGI/green screen to the video track, it's not a new track, but it's now modified. You take the audio track and run it through some filters to get better sounds, now that has a new modify date.
Of course, all this would depend upon the software actually changing the time stamps properly. I don't think most low price/free software is going to properly set details like this. And for most people, they won't even see the track time stamps or even care about them.