Authen::Captcha and GD::SecurityImage are two of the modules that do this. You may find code posted at Re: Authen::Captcha Segmentation Fault Under mod_perl useful. Related threads are Image Verification Program and Code to Block Scripts/Harwesters (GD based?)

cheers

tachyon

In reply to Re: How do you make on the fly images? by tachyon
in thread How do you make on the fly images? by Avitar

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