I have some recent iPhone photos with timestamps in the wrong timezone. In Windows PowerShell, exiftool -s -a -G1 *.heic | select-string 'date|heic' | select-string -notmatch file produces this for one of the files:

[IFD0]          ModifyDate                      : 2022:10:20 15:44:34
[ExifIFD]       DateTimeOriginal                : 2022:10:20 15:44:34
[ExifIFD]       CreateDate                      : 2022:10:20 15:44:34
[XMP-xmp]       CreateDate                      : 2022:10:20 15:44:34
[XMP-xmp]       ModifyDate                      : 2022:10:20 15:44:34
[XMP-photoshop] DateCreated                     : 2022:10:20 15:44:34
[Composite]     SubSecCreateDate                : 2022:10:20 15:44:34.263-03:00
[Composite]     SubSecDateTimeOriginal          : 2022:10:20 15:44:34.263-03:00
[Composite]     SubSecModifyDate                : 2022:10:20 15:44:34-03:00

The picture was taken at sea near a time zone boundary, and the iPhone got it wrong. The image was taken at 16:44:34-02:00, not 15:44:34-03:00.

I tried to fix this as follows,

exiftool '-datetimeoriginal+=1' '-offsettimeoriginal=-2:00' *.heic

but exiftool complains, "Error: Not a valid HEIC (looks more like a JPEG)". The files in question were downloaded from Google Photos, where they are stored in "storage saver" mode (i.e., lossily compressed).

How can I adjust the "when taken" timestamp(s) on these files?

  • \$\begingroup\$ Exiftool is telling you that the image is a jpeg, not a HEIC. In order to avoid corruption, it isn't editing the file because of this. Double check to make sure that it is jpeg or HEIC. If it is a jpeg, rename it to reflect that and then exiftool will allow you to make the edits in your command. \$\endgroup\$
    – StarGeek
    Nov 6, 2022 at 16:04
  • \$\begingroup\$ Despite the .HEIC extensions on the files, ImageMagick backs up ExifTool that they are actually JPEGs. The issue seems to be that when you download multiple files from the Google Photos web site and those files were originally uploaded from an iOS device in HEIC format, Google converts the files to JPEGs, but it retains the .HEIC extensions. Strangely, it does not do this when you download only a single file; then it changes the file extension to JPG. \$\endgroup\$ Nov 8, 2022 at 17:04


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Browse other questions tagged or ask your own question.