Efficient Melody Retrieval with Motif Contour Classes

This paper describes the use of motif contour classes for efficient retrieval of melodies from music collections. Instead of extracting incipits or themes, complete monophonic pieces are indexed for their motifs, using classes of motif contours. Similarity relations between these classes can be used for a very efficient search. This can serve as a first level search, which can be refined by using more computationally intensive comparisons on its results. The model introduced has been implemented and tested using the MUSITECH framework. We present empirical and analytical results on the retrieval quality, the complexity, and quality/efficiency trade-off.