SPARQL-DJ: The MIDI Linked Data Mashup Mixer for Your Next Semantic Party

Many datasets describing musical resources are published today as Linked Data, mainly focusing on metadata, notation, and audio features. However, the availability of musical data as Linked Data is often not enough for musicians, who need additional layers of software and queries to accomplish their workflows. Mashups are compositions created by blending two or more pre-recorded songs, and it has been shown that they can be generated by using SPARQL on top of MIDI music represented as Linked Data. In this demonstration, we showcase SPARQL-DJ, a web-based application implementing those layers for the workflow of generating MIDI mashups using Linked Data and SPARQL. The demonstration focuses on three parts: (1) coverage of the mashup composition workflow; (2) scoping of input retrieval for beatmaching by broadening text search and leveraging track annotations; and (3) management of off-beat and dissonance.