METS: A Status Report

1
METS A Status Report

• Jerome McDonough
• New York University
• jerome.mcdonough_at_nyu.edu

2
METS What is it?

• A XML document format for encoding digital
  library objects which can fulfill roles of SIP,
  AIP and DIP within the OAIS reference model
• Initial scope limited to objects comprised of
  text, image, audio video files
• Promote interoperability of descriptive,
  administrative and technical metadata while
  supporting flexibility in local practice

3
METS Why?

• If tools are to be developed that work with
  digitized archival objects across distributed
  repositories, these objects will require some
  form of standardization.
• The Making of America II Testbed Project A
  Digital Library Service ModelBernard J. Hurley,
  John Price-Wilkin, Merrilee Proffitt, Howard
  Besser

4
METS Whos to blame?

• Jerome McDonough (Editoral Board Chair), New York
  University
• Rick Beaubien, University of California
• Morgan Cundiff, Library of Congress
• Susan Dahl, University of Alberta
• Richard Gartner, Bodleian Library at Oxford
• Nancy Hoebelheirich, Stanford University
• Mark Kornbluh, Michigan State University
• Cecilia Preston, Preston Lynch
• Merrilee Proffitt, Research Libraries Group
• Richard Rinehart, BAM/PFA
• Mackenzie Smith, Massachusetts Institute of
  Technology
• Taylor Surface, OCLC
• Brian Tingle, California Digital Library
• Robin Wendler, Harvard University

5
METS Whos using it?

• CDL Content Mgmt./Digital Object Repository
• Cornell/UVA Fedora/Tibetan Himalayan Dig.
  Library
• Florida Center for Library Automation Union
  Catalog of Digital Materials, Digital Archive
• Göttingen Digitalisierungs-Zentrum
  Retrospective Digitization
• Harvard University Library -- biomedical image
  stacks, preservation audio, page-turned objects
• Library of Congress Audio-Visual Prototyping
  Project
• MIT DSPACE
• NYU Libraries Digital Repository, CRL Web
  Archiving

6
METS Whos using it?

• OCLC Digital Archive Implementation
• Oxford University Oxford Digital Library
• RLG Cultural Materials Service
• Stanford University Library/AIS Stanford
  Digital Repository
• University of Alberta Peels Prairie Provinces
  Project
• UC Berkeley Library Archival Collections,
  TOC/Indexes for off-site material, CS Tech Report
  (w/OAI Interface)
• Univ. of Chicago Library Digital Collections
• University of Graz, Austria Austrian Literature
  Online

7
METS Technical Components

• Primary XML Schema
• Extension Schema
• Controlled Vocabularies

8
METS XML Schema
METS Document
Header
Admin. MD
Link Struct.
Behaviors
Descript. MD
File List
Struct. Map
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Structural Map

• Object modeled as tree structure (e.g., book with
  chapters with subchapters.)
• Every node in tree can be associated with
  descriptive/administrative metadata and
• Individual/multiple files (or portions thereof)
  or
• Other METS documents

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Structural Map
ltdiv typebook labelHunting of the
Snarkgt ltdiv typechapter labelFit the
Firstgt ltfptrgtlt/fptrgt lt/divgt ltdiv
typechapter labelFit the Secondgt ltfptrgtlt/
fptrgt lt/divgt lt/divgt
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Link Structure

• Records all links between nodes in structural map
• Uses XLink/Xptr syntax
• Caveat Encoder make sure your structural map
  supports your link structure

12
Content Files Listing

• Records file specific technical metadata
  (checksum, file size, creation date/time) as well
  as providing access to file content
• Files are arranged into groups, which can be
  arranged hierarchically
• Files may be referenced (using Xlink) or
  contained within the METS document (in XML or as
  Base64 Binary)

13
Descriptive Metadata

• Non-prescriptive/Multiple instances
• Desc. metadata associated with entirety of METS
  object or subcomponents
• Desc. metadata may be internal (XML or binary) or
  external (referenced by XLink) to METS document

14
Administrative Metadata

• 4 Types Technical, Rights, Source Document,
  Digital Provenance
• Non-prescriptive/Multiple instances
• associated with entirety of METS object or
  subcomponents
• may be internal (XML/binary) or external (XLink)
  to METS document

15
METS Header

• Metadata regarding METS document
• Creation/Last Modification Date/Record Status
• Document Agents (Creator, Editor, Archivist,
  Preservation, Disseminator, Rights Owner,
  Custodian, etc.)
• Alternative Record ID values

16
Behaviors Section

• Multiple Behaviors allowed for any METS document
• Behaviors may operate on any part of METS
  document
• May provide information on API, service location,
  etc.

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METS Structure
18
METS Structure
Oral History
MARC21 Record
Introduction
Q1 Answer
AIFF Master
AES/EBU Tech. Metadata
Q2 Answer
TEI Tran-scription
Text Tech. Metadata
Time Code Link
IDREF Link
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METS Extension Schema

• Descriptive Metadata (DC, MARCXML, MODS)
• Administrative Metadata
• Technical
• image NISO Still Image (MIX)
• text NYU LOC A/V Prototyping
• audio AES/EBU (Real Soon Now) LOC A/V
  Prototyping
• video SMPTE (Not Real Soon) LOC A/V
  Prototyping
• IP Rights (XrML, ODRL, MPEG 21, Stanford)
• Digital Provenance (capture/migration) LOC A/V
  Prototyping OCLC/RLG Working Group (Soon than
  Id like)

20
METS Examples

• Afghanistan Digital Library
• Library of Congress Viewer
• NYU Multimedia Viewer
• METS Zooming Spaces

21
METS Example Time-Based Media
ltmfile ID"F01" MIMETYPE"image/gif"gt ltmfile
ID"F02" MIMETYPE"audio/wav"gt ltmfile ID"F03"
MIMETYPE"text/plain"gt
ltmdiv LABEL"slide 1"gtltmfptrgtltmpargt ltmarea
FILEID"F01"/gt ltmarea FILEID"F02"
BEGIN"000000.100" END"000003.500"
BETYPE"SMIL" EXTENT"2.5s" EXTTYPE"SMIL"/gt ltma
rea FILEID"F03" BEGIN"p01" END"p02"
BETYPE"IDREF"/gt lt/mpargtlt/mfptrgtlt/mdivgt
This, plus.
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METS Example Time-Based Media
ltbodygt ltp id"p01"gtRecovery from drug or alcohol
abuse can be a long lonely roadlt/pgt ltp
id"p02"gtHelp someone you lovelt/pgt ltp
id"p03"gtCall 1-800-444-6472lt/pgt ltp
id"p04"gtHelp Close the Health Gaplt/pgt ltp
id"p05"/gt lt/bodygt
this, along with an audio file and some XSLT,
gives you
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METS Example Time-Based Media
ltsmilgtltheadgtltlayoutgt ltroot-layout id"right"
width"320" height"404" background- color"green"
/gt ltregion id"visualarea" left"0"
top"0" width"100" height"240"/gt
ltregion id"textarea" left"0" top"242"
width"100" height"160"/gt lt/layoutgtlt/headgt ltbody
gtltpargt ltimg src"../image/gap01.gif"
region"visualarea dur"000031.000"
/gt ltaudio src"../audio/track01.wav" /gt lttext
src"track01.txt" region"textarea"
dur"000031.000"/gt lt/pargtlt/bodygtlt/smilgt
this, and
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METS Example Time-Based Media
QTtextfontGenevaplainsize12textColor
65535, 65535, 65535backColor 0, 0,
0justifycentertimeScale1000width320 hei
ght160timeStampsabsolutelanguage0textEnco
ding0 000000.000 Loading... 000000.100
Recovery from drug or alcohol abuse can be a long
lonely road 000004.500 Help someone you
love 000006.000 Call 1-800-444-6472 000008.
000 Help Close the Health Gap 000012.000
Closing... 000012.000
this.
25
METS Development Tools

• Harvard Java Toolkit http//hul.harvard.edu/mets/
• NYU XSLT for METS
• http//dlib.nyu.edu/metstools/
• More coming soon
• http//www.loc.gov/standards/mets/

26
METS Profiles
Learning Zen is a phenomenon of gold and dung.
Before you understand it, it's like gold after
you understand it, it's like dung.
27
METS Profiles
METS was designed to be flexible, so it could
adapt to your local practices, but that means

• different institutions can, and will, differ in
  how they define structural, administrative and
  descriptive metadata, even for the same work
• different institutions can, and will, differ in
  their use of content file formats
• different institutions can, and will differ in
  their use of rules of description, controlled
  vocabularies, etc., etc., etc.

So much for interoperability.
28
METS Profiles
METS profiles allow digital libraries to specify
constraints that they place on METS for ingest,
storage/processing or dissemination, including

• dictating use of particular extension schema,
  rules of description, and controlled vocabularies
• specifying arrangement and use of METS elements
  and attributes for particular classes of
  documents
• specifying the technical characteristics of data
  files within a METS object
• identifying tools for creating/processing METS
  documents compliant with a particular profile

29
METS Profiles

• An XML schema for METS profiles has been
  developed and distributed to the METS community
  for review.
• A registration process has been developed by the
  METS editorial board in cooperation with the Lib.
  of Congress Network Dev. MARC Stds Office.
• Registration is optional profiles are useful
  even without registration for defining local
  practice.

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METS Next Steps

• Better documentation
• Training sessions (all over the place)
• Tool development (particularly open source)
• Help spark extension schema development (video
  tech. metadata, IP rights, digital provenance)
• Work on controlled vocabularies for use in METS
• Establish registry of METS repositories

31
METS Further Info

• METS Web Site http//www.loc.gov/standards/mets
• METS Mailing List mets_at_loc.gov
• or contact me at jerome.mcdonough_at_nyu.edu