How to add 1 day to DateTimeOriginal

[drfranks]

What am I missing here?  It runs but does not update the files.  I had my year set to 2024 instead of 2025 so correcting it.

$  exiftool  -datetimeoriginal *.mp4
======== 20240216_075819_canonpowershotsx620hs.mp4
Date/Time Original              : 2024:02:16 07:58:19
======== 20240219_161503_canonpowershotsx620hs.mp4
Date/Time Original              : 2024:02:19 16:15:03
======== 20240219_161528_canonpowershotsx620hs.mp4
Date/Time Original              : 2024:02:19 16:15:28
    3 image files read

$ exiftool "-datetimeoriginal+=1:0:0 0:0:0" *.mp4
    0 image files updated
    3 image files unchanged

[Phil Harvey]

DateTimeOriginal in MP4 files is non-standard.  If this is a MP4 from a Canon camera, it is stored inside the ThumbnailImage.  ExifTool can't be used to write this directly, but it is possible to extract the thumbnail, update the tag, then write the thumbnail back again.

Add -G5 to your first command for details about exactly where this information is stored.

- Phil