Modular Design of the Music Encoding Initiative MEI DTD

1
Modular Design of the Music Encoding Initiative
(MEI) DTD

• Perry Roland
• Digital Library Research Development Group
• Alderman Library
• University of Virginia
• pdr4h_at_virginia.edu
• http//www.people.virginia.edu/pdr4h/

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MEI DTD modules

• mei.dtd driver
• meiExtensions.ent
• meiGis.ent
• meiKey.ent
• meiChars.ent
• meiNotats.ent
• meiClas.ent

• meiExtensions.dtd
• tagsets
• base.dtd
• head.dtd
• bar.dtd
• MIDI.dtd
• text.dtd

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"driver" dtd

• declares document elements
• "includes" remaining modules
• To do declare elements common to remaining
  modules in order to eliminate dependencies among
  modules

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Element names

• declare location of file containing parameter
  entities
• lt!ENTITY meiElementNames SYSTEM
  'meiGis.ent'gt meiElementNames
• parameter entities declare the default names of
  elements
• lt!ENTITY n.score score" gt
• each element "knows" its canonical name via a
  meiform attribute which has a FIXED value
• meiform CDATA FIXED 'score'

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Name flexibility allows

• longer, descriptive names for new users and user
  interface design
• lt!ENTITY n.score putScoreHere" gt
• shorter, mnemonic ones for experienced users and
  reduction of storage requirements
• lt!ENTITY n.score "s" gt
• internationalization
• lt!ENTITY n.score "partitur" gt
• lt!ENTITY n.score ??" gt
• extension mechanism based on concept name
• lt!ELEMENT foo (PCDATA)gt
• lt!ATTLIST foo meiform CDATA FIXED "note"gt

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Keywords

• declare location of file containing parameter
  entities
• lt!ENTITY meiKeywords SYSTEM 'meiKey.ent'gt
• keyword parameter entities declare
• rules or constraints which cannot be fully
  expressed in attribute declarations
  data-types
• lt!ENTITY ISODATE 'CDATA'gt
• lt!-- ISO date format YYYYMMDD --gt
• attribute value lists
• lt!ENTITY PITCHNAME '(abcdefg)'gt
• do attribute value lists belong in meiClas.ent
  instead?

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Characters

• declare location of file containing character
  entity declarations
• lt!ENTITY meiCharacters SYSTEM 'meiChars.ent'gt
  meiCharacters
• useful for discrete, pre-defined Unicode
  characters
• lt!ENTITY aacute "x00E1"gt
  lt!-- LATIN SMALL LETTER A WITH ACUTE --gt
• may be used for user-defined characters, but
  rendering is processor-dependent
• How can character rendering be defined within the
  document itself?

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Notations

• declare location of file containing notation
  declarations
• lt!ENTITY meiNotations SYSTEM 'meiNotats.ent'gt
  meiNotations
• notation declarations state acceptable media
  types
• lt!NOTATION jpeg SYSTEM "jpg"gt
• lt!NOTATION wav SYSTEM "wav"gt
• notations allow validation
• ltpb entityref"page1.jpeg" /gt ?
• ltpb href"page1.jpeg" /gt ?

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Attribute element classes

• declare location of file containing shared
  attributes and content models
• lt!ENTITY meiClasses SYSTEM 'meiClas.ent'gt
  meiClasses
• classes modified via meiExtensions.ent, not by
  direct editing of meiClas.ent!
• Do attribute value list declarations belong here
  instead of in meiKey.ent?

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meiClas.ent excerpts

• lt!ENTITY a.common
• "id ID
  IMPLIED
• type CDATA
  IMPLIED"gt
• lt!ENTITY m.events.log
• "n.beamn.beatrptn.btre
  mn.chordn.ftrem
• n.noten.padn.restn.
  spacen.tuplet"gt
• lt!ENTITY a.log.note
• "acci
  ACCIDENTAL.EXPLICIT IMPLIED
• artic
  ARTICULATIONS IMPLIED
• beam BEAMS
  IMPLIED
• dots
  AUGMENTDOT IMPLIED
• lyricsyl CDATA
  IMPLIED
• oct OCTAVES
  PROPAGATED
• pname
  PITCHNAME PROPAGATED
• pnum
  PITCHNUMBER IMPLIED
• tabfret CDATA
  IMPLIED
• tie TIES
  IMPLIED"gt

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MEIextensions.ent

• default declaration contains an empty string in
  case the user has no modifications
• lt!ENTITY meiExtensions.ent '' gt
  meiExtensions.ent
• declare location of file containing local
  modifications to MEI parameter entities in
  internal DTD subset
• lt!ENTITY meiExtensions.ent 'Chinese.ent' gt
  meiExtensions.ent
• because meiExtensions.ent is read before
  meiClas.ent, parameter entities declared in the
  file it points to override the default
  declarations

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Chinese.ent overrides default declarations

• lt!-- rename score element--gt
• lt!ENTITY n.score "2713835676" gt
• lt!- octave and pname values--gt
• lt!ENTITY OCTAVES "(lingyiersansiwuLiuQib
  ajiu)"gt
• lt!ENTITY PITCHNAME "(hesuyishangchegongti
  liuwu)"gt
• lt!-- turn off default declaration for note
  element --gt
• lt!ENTITY note 'IGNORE'gt
• lt!- declare new attributes --gt
• lt!ENTITY a.log.note
• "oct OCTAVES
  REQUIRED
• pname PITCHNAME
  REQUIRED"gt

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MEIextensions.dtd

• default declaration contains an empty string in
  case the user has no modifications
• lt!ENTITY meiExtensions.dtd '' gt
  meiExtensions.dtd
• declare location of file containing local
  modifications to MEI elements
• lt!ENTITY meiExtensions.dtd 'Chinese.dtd' gt
  meiExtensions.dtd
• because meiExtensions.dtd is read before the
  other tagsets, elements declared in the file it
  points to override the default declarations
• however, default element declarations must still
  be explicitly "turned off"

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Chinese.dtd

• re-declaration of existing element content model
• lt!ELEMENT n.note (n.accidn.artic)gt
• lt!ELEMENT n.note(n.accidn.articn.pitch
  )gt
• and declaration for new element
• lt!ELEMENT n.pitch (PCDATA)gt
• lt!ATTLIST n.pitch
• meiform CDATA FIXED
  'pitch'
• a.common gt

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Modular Design of the Music Encoding Initiative
(MEI) DTD

• Perry Roland
• Digital Library Research Development Group
• Alderman Library
• University of Virginia
• pdr4h_at_virginia.edu
• http//www.people.virginia.edu/pdr4h/