RenRot is a simple but very useful command-line tool. It renames photo files based on information in the EXIF tags within the photo file. By default, it will rename each photo to the year, month, day, hour, minute, and second that it was taken. It will also rotate images based on the orientation data in the EXIF tags, if present (this requires a camera with a mercury switch or other orientation-sensing mechanism).
You can use the -n option to specify a naming template using a syntax similar to that used by the date command -- so you could rename files to the format YYYY-MM-DD-c-Iiii.jpg, where YYYY is the year, MM is the month, DD is the day, cc is a sequence (counter) number, and iii is the ISO sensitivity, using this command:
$ renrot -n "%Y-%m-%d-%c-%I.jpg" *.jpg
RenRot offers a number of other features, including aggregation (grouping into directories by moving files or creating symlinks), which can be performed according to gaps between image groups, the date on which each photo was taken, or custom criteria. RenRot can also add (or change) EXIF tags to store information such as comments about the photos. The well-written manpage for the program (man renrot) has all of the details.
Installing from the command line: yum install renrot Installing using the graphical installer: Applications > Graphics > renrot Menu location after installation: (none) Command: /usr/bin/renrot Upstream website:http://freshmeat.net/projects/renrot/
Yes, jhead does. But jhead hasn't included some interesting features like renrot ones: virtual rotate (starting from ~0.24) or contact sheet generator framework (starting from 1.0).
And the main difference is in backends. ExifTool supports at most of cameras especially MakerNotes tags. Other libraries and programs are hardly made it.