Resetting Date Time photo taken from EXIF data

[velani]

Hi All,

This is my first post. Please be gentle 

I have recently started using Picasa v3.9 to do face recognition in my thousands of photos. It is a neat feature and I thought it was great that I would be able to find all the photos of a particular person someday.  I allowed Picasa to write back name associated with face recognized back to the photo.

Well, that changed the date and time stamp of the photo from taken to current date and time. Now I have a huge mess on my hands and would like to go reset all the date and time photo taken to its camera capture date and time, which was all accurate.

Can I use the ExifTool to fix all current date and time back to the picture taken date and time from the EXIF information?

Has anyone had this issue and if so, how else did you fix the problem?

[StarGeek]

Try this:

ExifTool "-CreateDate<exif:DateTimeOriginal" <FILE/DIR>

Myself, while I love Picasa's facial recognition ability, I don't let it write anything to my files.  I don't know if it currently messes up metadata but when I first started using it, it would stomp all stuff like the MakerNotes.  And this would include automatically writing to the file XMP:Description if I didn't click in the box to put a name to a face just right.

Currently, I use Picasa to tag faces, but don't let it save the info to the file.  I then use AvPicFaceXmpTagger to write the face tags into the Microsoft XMP (XMP-MP) tags.  This is the structure created by Adobe and Microsoft and used by Windows Live Photo Gallery.  AvPicFaceXmpTagger uses ExifTool to copy the tags.

I then use ExifTool with a special config file to remove the unidentified and deleted faces and then copy/convert the Microsoft face tags to the Picasa face tags (XMP-mwg-rs).  See this thread for Phil's config file that will do that.  If you want to leave the unidentified faces in, see this thead for a config file to use to just copy the tags.

[velani]

Thanks a lot for your reply StarGeek and the tips. I will give this a try and am sure it will get me out of the mess I am in.  Thanks.