Not all timestamps being corrected in MP4 file

[ahmadka]

Hi everyone. I have an MP4 video (shot using a Panasonic camera) in which I was to remove 5 seconds from all timestamps. I've used the command ...

exiftool "-time:all-=00:00:05" v.MP4

.. and that substracts 5 seconds from most timestamps but not all. Can someone let me know how to have this work for all timestamps, including the one not currently being updated (highlighted in the picture below)? :



Thanks in advance!

[StarGeek]

The first two tags are part of the EXIF group and the third one is a MakerNotes, which is also embedded in the EXIF block.  EXIF data in a video is non-standard.  There isn't a spec to detail how it should appear in the file.  As a result, every camera company writes the data in a different way, sometimes differing between different models from the same company.j

As a result, it is extremely hard for any program to edit this data without possibly losing data or corrupting the video.  Exiftool can edit the EXIF data in some videos, but not all of them.  You won't find any program that does.  At least, none that I'm aware of.

The Composite tags don't exist in the file.  Exiftool generates them on the fly.  They're meant help make some data easier to read for humans or make it easier to copy the data.  In this case, these Composite tags are generated by combining the data/time tag, DateTimeOriginal for example, and the associated subseconds (SubSecTimeOriginal) and time zone (OffsetTimeOriginal) tags.  See the Composite tags page for more details.