If you have a digital camera, you probably have a large number of photos. What's more, they probably have names like DSCF0024, which aren't very meaningful.
You can rename large collections of photos at once using a batch renaming program, which saves you the effort of renaming them individually.
Bulk Rename is a graphical interface for renaming any type of file. It is very powerful, intuitive, and easy to use, and allows you to insert, overwrite, remove, and number files. Unfortunately this program doesn't read the EXIF information embedded in the photos. Bulk Rename is part of Thunar File Manager.
To install Bulk Rename, press Applications -> Add/Remove... and then select Bulk Rename from the Accessories category.
Phatch is an user friendly, cross-platform Photo Batch Processor and Exif Renamer with a nice graphical user interface. Phatch handles all popular image formats and can duplicate (sub)folder hierarchies. Phatch can batch resize, rotate, apply shadows, perspective, rounded corners. See http://photobatch.wikidot.com/.
Phatch is found in Ubuntu's repositories.
This is an example how to rename in Phatch 0.1
Warning: Phatch 0.2 (Karmic) uses a different syntax: use <##index> instead of <##>.
jhead is a command-line utility that can be used to manipulate EXIF data. It is able to handle batch renaming and is very useful in cases when the date of the picture is required as part of the name.
Install the jhead package to use jhead.
To use jhead, press Applications -> Accessories -> Terminal and type a command such as the following:
jhead -n%y%m%d-%02i *.jpg
For help, type jhead -h or visit http://www.sentex.net/~mwandel/jhead/.