Like many of these higher level tasks there are a number perspectives on how to solve this problem (and what exactly this problem is). Here are a couple examples to start:

• MPEG-7 Audio Classification/Indexing scheme This was largely a work of MichaelCasey.
• BenFields Master's Thesis explores a method of top down classification that builds upon MPEG-7 audio classifiers.
• others to come...

-- BenFields - 29 Jan 2007