Musical scores are traditionally retrieved by title, composer or subject cl
assification. Just as multimedia computer systems increase the range of opp
ortunities available for presenting musical information, so they also offer
new ways of posing musically-oriented queries. This paper shows how scores
can be retrieved from a database on the basis of a few notes sung or humme
d into a microphone. The design of such a facility raises several interesti
ng issues pertaining to music retrieval. We first describe an interface tha
t transcribes acoustic input into standard music notation. We then analyze
string matching requirements for ranked retrieval of music and present the
results of an experiment which tests how accurately people sing well known
melodies. The performance of several string matching criteria are analyzed
using two folk song databases. Finally, we describe a prototype system whic
h has been developed for retrieval of tunes from acoustic input and evaluat
e its performance.