Music representation of score, sound, MIDI, structure and metadata all integrated in a single multilayer environment based on XML

In this chapter, we will analyze the heterogeneous contents involved in a comprehensive description of music, organizing them according to a multilayer structure. Each layer we can identify corresponds to a different degree of abstraction in music information. In particular, our approach arranges music contents in six layers: General, Music Logic, Structural, Notational, Performance, and Audio. In order to reflect such organization, we will introduce a new XML-based format, called MX, which is currently undergoing the IEEE standardization process (IEEE SA PAR1599). In an MX file, music symbols, printed scores, audio tracks, computer-driven performances, catalogue metadata, and graphic contents related to a single music piece can be linked and mutually synchronized within the same encoding. The aforementioned multilayer structure allows us to gather and organize heterogeneous contents, leaving them encoded in well-known and commonly used formats aimed at music description.