extracting a specific melody/beat/rhythm from a specific instument from a mixed wave (or other music format) file

Question

Is it possible to write a program that can extract a melody/beat/rhythm provided by a specific instument in a wave (or other music format) file made up of multiple instruments?

Which algorithms could be used for this and what programming language would be best suited to it?

Answer 1

This is a fascinating area. The basic mathematical tool here is the Fourier Transform. To get an idea of how it works, and how challenging it can be, take a look at the analysis of the opening chord to A Hard Day's Night.