METS: A Status Report

1. METS: A Status Report Jerome McDonough New York University jerome.mcdonough@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: Who’s 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: Who’s 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: Who’s 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 – Peel’s 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

9. 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

10. Structural Map <div type=“book” label=“Hunting of the Snark”> <div type=“chapter” label=“Fit the First”> <fptr>…</fptr> </div> <div type=“chapter” label=“Fit the Second”> <fptr>…</fptr> </div> … </div>

11. 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.

17. 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

19. 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 I’d like)

20. METS Examples • Afghanistan Digital Library • Library of Congress Viewer • NYU Multimedia Viewer • METS + Zooming Spaces

21. METS Example: Time-Based Media <m:file ID="F01" MIMETYPE="image/gif"> <m:file ID="F02" MIMETYPE="audio/wav"> <m:file ID="F03" MIMETYPE="text/plain"> <m:div LABEL="slide 1"><m:fptr><m:par> <m:area FILEID="F01"/> <m:area FILEID="F02" BEGIN="00:00:00.100" END="00:00:03.500" BETYPE="SMIL" EXTENT="2.5s" EXTTYPE="SMIL"/> <m:area FILEID="F03" BEGIN="p01" END="p02" BETYPE="IDREF"/> </m:par></m:fptr></m:div> This, plus….

22. METS Example: Time-Based Media <body> <p id="p01">Recovery from drug or alcohol abuse can be a long lonely road</p> <p id="p02">Help someone you love</p> <p id="p03">Call 1-800-444-6472</p> <p id="p04">Help Close the Health Gap</p> <p id="p05"/> </body> …this, along with an audio file and some XSLT, gives you…

23. METS Example: Time-Based Media <smil><head><layout> <root-layout id="right" width="320" height="404" background- color="green"/> <region id="visualarea" left="0" top="0" width="100%" height="240"/> <region id="textarea" left="0" top="242" width="100%" height="160"/> </layout></head> <body><par> <img src="../image/gap01.gif" region="visualarea“ dur="00:00:31.000" /> <audio src="../audio/track01.wav" /> <text src="track01.txt" region="textarea" dur="00:00:31.000"/> </par></body></smil> …this, and…

24. METS Example: Time-Based Media {QTtext}{font:Geneva}{plain}{size:12}{textColor: 65535, 65535, 65535}{backColor: 0, 0, 0}{justify:center}{timeScale:1000}{width:320} {height:160}{timeStamps:absolute}{language:0}{textEncoding:0} [00:00:00.000] Loading... [00:00:00.100] Recovery from drug or alcohol abuse can be a long lonely road [00:00:04.500] Help someone you love [00:00:06.000] Call 1-800-444-6472 [00:00:08.000] Help Close the Health Gap [00:00:12.000] Closing... [00:00:12.000] …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.

30. 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@loc.gov • …or contact me at jerome.mcdonough@nyu.edu