b8 is a spam filter implemented in PHP 5. It is intended to keep your weblog or guestbook spam-free. The filter can be used anywhere in your PHP code and tells you whether a text is spam or not, using statistical text analysis. See How does it work? for details about this.
To be able to do this, b8 first has to learn some spam and some ham example texts to decide what's good and what's not. If it makes mistakes classifying unknown texts, they can be corrected and b8 learns from the corrections, getting better with each learned text.
Basically, b8 is a statistical ("Bayesian") spam filter like Bogofilter or SpamBayes, but it is not intended to classify emails. On the other hand, I don't know a good spam filter (or any spam filter that isn't just example code how one could implement a Bayesian spam filter in PHP) that is intended to filter weblog or guestbook entries, and here we have the raison d'être for b8!
Caused by this fact, the way b8 works is slightly different from most of the Bayesian email spam filters out there. See What's different? if you're interested in the details.
The whole documentation lives inside the readme.
If you're interested in the performance of b8 and a discussion about the best settings for the filter, see the Statistical Discussion.
Meanwhile, several sites seem to use b8. If you also do or plan to do it, it would be really cool if you wrote me an email. Just because I'm curious where the filter does his work :-)
To all Windows users: perhaps, you don't know the file format ".tar.gz" … on UNIX systems, it is widely used. If you don't have a packing program that can handle it, I recommend 7-zip.
b8-0.5.2.tar.gz
48.4 KB, Last change: 2011-04-19
Older versions:
b8-0.5.1.tar.gz (48.4 KB)
b8-0.5-r1.tar.gz (43.8 KB)
b8-0.5.tar.gz (41.8 KB)
The PHP 4 compatible version of b8 is probably still in use and receives bugfixes and updates for this reason at first. The sources are located in branch_0.4.x (including version 0.3.3, the first version named "b8").
The first b8 releases named "bayes-php" initially are still availible in old_releases for historical reasons.