Introduction
The MEI (Music Encoding Initiative) is an encoding toolset meant for modeling
music information (Roland, 2006). This does not refer to audio, but to the
symbolic representation of Common Music notation (CMN), the “standard” form of
music notation used between 1700 and 1935 (see Fig. 1). MEI is an XML
application expressed in DTD form (for the present), with a TEI-like header
(Fig. 2), a
<music> element instead of <body>, and <front> and <back> to
accommodate text. The goals for MEI are to encode CMN “out of the box”, to limit
verbosity without compromising the self-documenting aspect of XML, to support
repertoires other than CMN, and to support creation of multi-lingual interfaces
by allowing generic identifier names to be changed, all to better enable
creation of scholarly editions. In this poster presentation we highlight the
recent developments made to improve and extend MEI with a special emphasis on
the impacts these developments can have on digital musicology and scholarship. 
Figure 1. Sample CMN rendition of "Quem queritis"
<?xml version="1.0" encoding="UTF-8"
standalone="no">
<!DOCTYPE mei SYSTEM
"http://www.lib.virginia.edu/digital/resndev/mei/mei17b/
mei17b.dtd">
<mei version="1.7b">
<meihead>
<meiid/>
<filedesc>
<titlestmt>
<title>"Quem queritis"</title>
</titlestmt>
<notesstmt>
<bibnote type="encoding-date">2003-03-15</
bibnote>
</notesstmt>
</filedesc>
<profiledesc>
<langusage>
<language id="la"/>
</langusage>
</profiledesc>
<revisiondesc>
<change>
<changedesc>
<p>Transcoded from MusicXML
version 1.0</p>
</changedesc>
<date>2006-09-26-04:00</date>
</change>
</revisiondesc>
</meihead>
Figure 2.Sample of the TEI-like MEI header for
"Quem queritis".
Recent Developments
MEI is extending its notation encoding capacity beyond CMN. While most
representations of notation have been limited to CMN, MEI has a TEI P4-like
extension/restriction mechanism which can be used to expand the universe of
sources to which it can be applied. Work is progressing in two particular areas:
“White mensural” notation and “Medieval neumatic” notation. Both of these
developments also better situate MEI as an encoding mechanism for serious
digital musicology (see Section 3).
Mensural notation is a musical notation system used from the later part of the
13th century until about 1600. The name “mensural” refers to the capacity of
this system to notate complex rhythms with great exactness and flexibility.
Mensural notation was the first system used for European music that
systematically used individual note shapes to denote temporal durations.
Measure-less music requires structural reorganization, or score-by-staff
encoding rather than score-by-measure-by-staff encoding: the staff must directly
allow features previously available only within
<measure>, such as for timed events. MEI is introducing
new concepts to enable such encoding: events -- ligature, mensuration and
proportion signs; orthographic vs. semantic accidentals; barlines, and new
attributes and attribute values. Neumes are the basic elements of Western and Eastern systems of musical notation
prior to the invention of five-line staff notation. Neumatic notation eventually
evolved into modern musical notation, but remains standard in modern editions of
plainchant. MEI is introducing new concepts to enable encoding of this system:
single and compound neumes, ligatures, mensuration and proportion indicators,
orthographic accidentals, custos, interpretative marks (episema, liquescent
neumes, quilisma) that can be treated as timed events, mora (an augmentation
dot) that may be handled the same as a modern augmentation dot, and new
attributes and attribute values.
MEI is now supporting data collection via MusicXML (Good, 2002), a translator
and interchange format for common Western musical notation from the 17th century
onwards. A new 2mei XSL style sheet facilitates transformation of MusicXML to
MEI, creating an input path from any software that supports export of MusicXML.
On average the resulting MEI files are only 51% as large as the original
MusicXML files.
Enhancing Support for Digital Musicology and Scholarly Editions
MEI has been gaining favorable reception among those engaged in digital music
scholarship. For example, the MeTAMuSe project has said, "In contrast to
MusicXML, which is the de facto industry standard, but which is rather limited
in the representation of musicological concepts such as multiple divergent
sources, MEI has definite advantages in the musicological context" (Byrd et al.,
2006). MEI has also been described as one of "two really serious contenders" in
this problem space (Kay, 2004).
Digital critical editions of music start with the encoding of the musical
sources, and then add layers for presentation and meaning. MEI's improved
capacity to encode multiple types of notation, provide support for
non-transcriptional text commentary/annotation, as well as improved methods of
data capture into the encoding format and data export will hopefully foster new
efforts to create scholarly critical editions using XML. Such content-based
encoding modeled on text encoding formats is not only best-suited to the
development of these digital editions, but can potentially best document the
intellectual process of the development of the corpus, making the critical work
better suited for verification and scholarly argument.
MEI is well-suited for the creation of scholarly editions that document the
creation and revision history of a single musical composition. In MEI, a single
file supports encoding of the data common to all sources only once, rather than
requiring redundant markup and encoding in multiple files. The
<source> element holds bibliographic and physical
description of a single source document and can be linked to specific data via
its data attribute, while data can be linked to the source via the source
attribute, a mechanism not unlike the “declarable/ declaring” attributes in TEI.
When the meiCrit parameter entity is enabled, parallel alternative encodings are
possible at the score, measure, and staff levels. This feature would be
particularly useful for the construction of such scholarly editions as the
“Online Chopin Variorum Edition” (http://www.ocve.org.uk/). In the case of manuscript music, the <handlist> element in the header and the “hand”
attribute (available on most music content elements) allow one to track the
scribes, copyists, etc. who notated the music. MEI now supports non-transcriptional text commentary/annotation. The
<annot> element provides a way to group
participating events, the notes that form a descending bass line, for example,
and provide a label for the group. An editorial or analytical observation,
encoded elsewhere, may be pointed to using the linking attributes.
Alternatively, the observation may be included directly within the <annot> element. Ongoing and Future Work
Work is progressing to support two modes of visualization and export. The first
is a conversion from MEI to MusicXML which will allow any software that reads
MusicXML to display/manipulate the data. This is analogous to the method, i.e.,
conversion to HTML which is used to display SGML/XML. This MEI-to-MusicXML
conversion, is, however, lossy. The second mode, direct conversions to other
internal representations, requires writing a filter for each existing data
format. This is a time-consuming task, but will greatly reduce data loss.
Also, additional elements necessary for manuscript encoding are planned:
<add> (for something added by another person
or at a later date), <del> (for something
marked out), <unclear> (for illegible
passages), <damage>(damage to the carrier),
<supplied> (for data supplied by the
editor), and <handshift> to indicate a change
in scribal hands. Appendix
<work>
<music>
<mdiv>
<score>
<scoredef>
<staffgrp>
<staffdef
n="1" id="P1" label.full="Voice" clef.line="2" clef.shape="G"
midi.div="2"/>
</staffgrp>
</scoredef>
<section>
<measure
n="1" id="d1e18" right="dbl">
<staff def="1">
<layer def="1">
<note id="d1e32" tstamp="0"
pname="g" oct="4" dur="4" dur.ges="2" stem.dir="up">
<verse n="1">
<syl>Quem</syl>
</verse>
</note>
<note id="d1e53" tstamp="2" pname="f"
oct="4" dur="4" dur.ges="2" stem.dir="up"/>
<note
id="d1e69" tstamp="4" pname="d" oct="4" dur="4" dur.ges="2"
stem.dir="up">
<verse n="1">
<syl
wordpos="i" con="d">que</syl>
</verse>
</note>
<note
id="d1e90" tstamp="6" pname="f" oct="4" dur="4" dur.ges="2"
stem.dir="up"/>
<note id="d1e104" tstamp="8" pname="e"
oct="4" dur="4" dur.ges="2" stem.dir="up"/>
<note
id="d1e120" tstamp="10" pname="f" oct="4" dur="4" dur.ges="2"
stem.dir="up">
<verse n="1">
<syl
wordpos="m" con="d">ri</syl>
</verse>
</note>
{CODE DELETED FOR
SPACE}
</measure>
</section>
</score>
</mdiv>
</music>
</work>
</mei>