exiv2

EXIF/IPTC metadata manipulation tool
Exiv2 can:
.
* print the Exif metadata of JPEG, TIFF and several RAW image formats as
summary info, interpreted values, or the plain data for each tag
* print the IPTC metadata of JPEG images
* print, set and delete the JPEG comment of JPEG images
* set, add and delete Exif and IPTC metadata of JPEG images
* adjust the Exif timestamp (that's how it all started...)
* rename Exif image files according to the Exif timestamp
* extract, insert and delete Exif metadata, IPTC metadata and JPEG comments
* extract, insert and delete the thumbnail image embedded in the Exif metadata
* fix the Exif ISO setting of picture taken with Nikon cameras