Vorras Antibot is an image generation program that prevents automatic form submission by robots. If your web site is being overwhelmed with spam, automatic registrations, automatic forum or classified ad submissions etc., Vorras Antibot can solve this problem by introducing a picture in your HTML forms that only a human can recognize.
How does it work?
Vorras Antibot generates a random sequence of alphanumeric characters and a picture in PNG format that shows this sequence. It returns the filename of the picture and the sequence in encrypted (hashed) format. The filename and encrypted sequence can then be stored in your HTML form. The user who attempts to fill out the form has to look at the picture and type in the sequence he sees. When the form is submitted the sequence the user typed in is encrypted as well (hashed) and compared to the original sequence. If the sequences match the user passes the test, else it is necessary to re-try. See the Demo on our website to get an idea of how this works.
Vorras Antibot uses pre-existing PNG files to form the character sequence in PNG format. These files are graphic files of alphanumeric characters in PNG format, and are provided when you download Vorras Antibot. If you want to change the existing PNG files you can replace with your own as follows:
Use any graphics package to create png files for all letters and numbers and name them as a.png, b.png,..., 0.png, 1.png, ...
Upload them on your server and place them in the data subdirectory inside the Vorras Antibot directory.
Run the parseidat.py script. This will generate the intermediate format files a.dat, b.dat etc. necessary to run Vorras Antibot.
After you complete the steps above you can re-run Vorras Antibot with your new graphic files. For more information please also see the README file which accompanies the Antibot software.
# COPYRIGHT NOTICE:
# Copyright 2002 Vorras Corporation. All Rights Reserved.
# This program is being distributed as shareware. It may be used and
# modified free of charge for personal, academic, government or non-profit
# use, so long as this copyright notice and the header above remain intact.
# Any commercial use should be registered. Please also send me an email,
# and let me know where you are using this script. By using this program
# you agree to indemnify Vorras Corporation from any liability.
# Selling the code for this program without prior written consent is
# expressly forbidden. Obtain written permission before redistributing this
# program over the Internet or in any other medium. In all cases
# copyright and header must remain intact.