OSBF-Lua (Orthogonal Sparse Bigrams with confidence Factor) is a C module for text classification written for Lua.

It is a port of the OSBF classifier implemented in CRM114: osbf-lua: http://crm114.sf.net.

The OSBF-Lua lib and spamfilter.lua were designed and implemented by Fidelis Assis, who holds the copyright.