Transforming XML Into Music Notation Baron Schwartz, Computer Science Perry Roland, Digital Library Worthy Martin, Computer Science

Overview

• Project Motivation • MEI and Research Objectives • XML and XSLT • A Sample Transformation • Results and Conclusions

Motivation

• There is no good, universal way to encode musical data in a computer file – There are dozens of good ones for specific purposes – There are many uses: analysis, printing, and bibliography to name a few – Commercially important: $711 million/yr industry • There is a huge amount of material – UVA Library has 65,000+ scores and books – RISM project identified 1.5 million works – 50 years ago!

MEI and This Project

• MEI – the Music Encoding Initiative – An XML file format by Perry Roland – Designed to enable storing and retrieving musical information – Not an audio file format – “music” is an abstract concept • My job: prove the MEI concept – Transform MEI-encoded music into notation

Transformation

• I used XSLT to transform the files • Typesetting music is complicated, so I used Mup as an intermediate format

XSLT Script MEI File XSLT Processor Mup File Mup Notation

XML

XSLT

… do something …

… do something …

… do something …

XSLT

XSLT Processor

Sample File Fragments

MEI Mup 1: 4c; 4e; 2g; bar

Results and Conclusions

• MEI can represent notation • MEI is probably useful for other purposes • Future work – More transformations – Native file format

Are there any other formats?

• MIDI – Commonly used, but very limited • MusicXML – Commercially motivated – Explicitly designed for interchange – Some serious design mistakes

What about MIDI?

• MIDI encodes a single performance • MIDI can’t tell a D-flat from a C-sharp • MIDI can’t store complicated information, such as visual layout

What Are the Requirements?

• Comprehensive • Declarative • Explicit • Interpreted • Hierarchical • Formal • Flexible • Extensible

What Uses Exist?

• Notation (most important) • Interchange & Transmission • Analysis • Preservation • Historical Works • E-Texts for Digital Libraries • Searching and Cataloguing/Bibliographies • Automatic Performance

Other Work

• Changes to the MEI format – Representing information atomically • Suggestions to preserve MEI’s flexibility – A rendering model – A definition for auxiliary languages – A stylesheet namespace model