A technical approach and distributed model for validation of digital objects

D-Lib Magazine

Volumn 12, Issue 5, 2006, Pages 37-46

  Littman, Justin ^a  

^a LIBRARY OF CONGRESS   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 33646743434     PISSN: 10829873     EISSN: 10829873     Source Type: Journal    
DOI: 10.1045/may2006-littman     Document Type: Conference Paper

References (26)

1. The Library of Congress / Ameritech National Digital Library Competition (1996-1999), 〈http://memory. loc.gov/ammem/award/index.html〉.
2. Global Gateway: Collaborative Digital Libraries (Library of Congress, 〈http://international.loc.gov/intldl/ find/digital_collaborations. html〉.
3. National Digital Newspaper Program, 〈http://www.loc.gov/ndnp〉
4. For the purposes of simplification, discussion of reel objects will be omitted. Reel objects reflect the fact that most of the newspapers are being digitized from microform by representing the physical arrangement of frames on the reel.
5. At least for the first phase, the page-oriented approach to newspaper will be taken instead of the articleoriented approach. The NDNP team determined that a page-oriented approach provides the base level of access required by users, while still offering obvious production cost efficiencies.
6. Metadata Encoding & Transmission Standard (METS), 〈http://www.loc.gov/standards/mets〉.
7. MARC 21 XML Schema, 〈http://www.loc.gov/standards/marcxmal〉
8. Metadata Object Description Schema (MODS), 〈http://www.loc.gov/ standards/mods〉.
9. The newspaper title bibliographic and holding records are derived from the USNP-created Newspaper Union List currently maintained by OCLC Online Computer Library Center.
10. METS / ALTO XML Object Model, 〈http://www.ccs-gmbh.com/alto. The ALTO schema supports encoding OCR-recognized text and the position of that text on the source image at the word level.
11. Metadata for Images in XML Standard (MIX), 〈http://www.loc.gov/ standards/mix〉.
12. Data Dictionary - Technical Metadata for Digital Still Images, 〈http://www.niso.org/committees/ committe_au.html〉.
13. PREMIS: Preservation Metadata Maintenance Activity, 〈http://www. loc.gov/standards/premis〉.
14. METS Profiles, lang;http://www.loc.gov/standards/mets/mets-profiles. html〉.
15. For example, for the issue template see 〈http://www.loc.gov/ndnp/ xml/issue Template.xml〉.
16. See NDNP Technical Specifications, http://www.loc.gov/ndnp/techspecs. html〉.
17. Because of the Library's limited experience with JPEG2000 and the relative complexity of the specification, LC contracted with Robert Buckley, Xerox Research Fellow, to assist in the development of the JPEG2000 profile. For the JPEG2000 profile, see http://www.loc.gov/ndnp/pdf/JPEG2kSpecs.pdf〉.
18. JHOVE JSTOR/Harvard Object Validation Environment, 〈http://hul. harvard.edu/jhove.〉
19. After removing some "final" statements and changing some "private" methods to "public," extending JHOVE modules was relatively straight-forward.
20. In at least one case, the NDNP profiles required relaxing JHOVE's validation - the NDNP TIFF profile does not require values to be word offset. It is the NDNP team's experience that many TIFF generators and most TIFF renderers ignore the word offset rule, which is ambiguous in the TIFF specification.
21. http://www.schematron.com. Schematron has been submitted to the International Organization for Standardization.
22. The test was performed using a sample of two issues, each composed of four pages, on a desktop with an Intel Pentium 4 2.4 GHz CPU and 1 gigabyte of RAM. This is a significant improvement over earlier versions of the NDNP Validation Library, which performed the same test in 26 seconds per page.
23. In many cases awardees will use vendors to create all or part of the digital objects. The distributed validation strategy also allows awardees to ensure that their vendors provide valid digital objects.
24. For an excellent introduction to digital signatures, see 〈http://www.dlib.org/dlib/june05/bekaert/06bekaert. html.〉.
25. W3C XML-Signature Syntax and Processing 〈http://www.w3.org/TR/ xmldsig-core/〉.
26. The test was performed using the same sample and machine as described previously for the informal validation test.