|The New Zealand Digital Library MELody inDEX|
McNab, R. J., Smith, L. A., Bainbridge, D., Witten, I. H. (1997) D-Lib Magazine; May.
Trying to identify a melody from just a few bars? Some tune buzzing round your head, bugging you? If you ever want to discover a song’s name but can only remember a few notes, the New Zealand Digital Library’s Web-based melody index is the service for you! You can sing (or hum, or play) a few notes and search for the tune in a database of 9,400 folk songs. You get back the notes you sang in musical notation, along with a ranked list of matching tunes. You can listen to the melodies, view them in musical notation, and download them in a variety of popular formats. This paper describes the MELDEX system, designed to retrieve melodies from a database on the basis of a few notes sung into a microphone. It accepts acoustic input from the user, transcribes it into the ordinary music notation that we learn at school, then searches a database for tunes that contain the sung pattern, or patterns similar to it. Retrieval is ranked according to the closeness of the match. A variety of different mechanisms are provided to control the search, depending on the precision of the input. This article presents an analysis of the system’s performance using different search criteria involving melodic contour, musical intervals and rhythm. Tests were carried out using both exact and approximate string matching. Approximate matching uses a dynamic programming algorithm designed for comparing musical sequences.