You might want to look into Image::Magick which is on CPAN under Perl-Magick. This assumes that you want to make a graphical image out of some text string that is sent in.

I would recommend png for the file format to best preserve the look of the text in the least proprietary way.

A graphic file of a sentance will be orders of magnitude larger to store than the sentance.

GD might also do this sort of thing.