use for to iterate over that list and extract caption
use s/// to massage $Caption into an appropriate filename (no newlines, etc, etc, Regexp::English might help you compose a regex)
combine caption with original filename ( DSC03753.JPG becomes DSC03753-NudeNodeReaper.JPG)
DO NOT ATTEMPT RENAMING (How can I reliably rename a file?) until you're sure your caption is producing good filenames -- produce a rename script (of shell commands) first