Medieval and Renaissance documents: Reformatting (Part 3)

Metadata is information recoded within the captured image that describes the image/document being reformatted. Metadata is used for cataloging the images and sharing them. It is common to distinguish between three basic kinds of metadata. The first is descriptive metadata, which helps users find objects, distinguish one object from another, and understand the subject or contents of objects. The minimum descriptive elements include:

--Identifier: Primary identifier should be unique to the digital resource (at both object and file levels). Secondary identifiers might include identifiers related to the original (such as Still Picture ID) or Record Group number (for accessioned records)
--Title/Caption: A descriptive name given to the original or the digital resource, or information that describes the content of the original or digital resource
--Creator (If available): Describes the person or organization responsible for the creation of the intellectual content of the resource
--Publisher Agency or agency acronym: Description of responsible agency or agent

The second type of metadata is administrative metadata, which helps collection managers keep track of objects for such purposes as file management, rights management, and preservation. Administrative metadata comprises both technical and preservation metadata, and is generally used for internal management of digital resources. It may include information about rights and reproduction or other access requirements, selection criteria or archiving policy for digital content, audit trails or logs created by a digital asset management system, persistent identifiers, methodology or documentation of the imaging process, or information about the source materials being scanned. Administrative metadata may also encompass repository-like information, such as billing information or contractual agreements for deposit of digitized resources into a repository.

The third type of metadata is structural metadata, which documents relationships among objects, such as the relationship between articles, issues, and volumes of serial publications, or the pages and chapters of a book. Structural metadata ties the various parts of a digital resource together in order to make a useable, understandable whole. Examples of structural metadata might include whether the resource is simple or complex (multi-page, multi-volume, has discrete parts, contains multiple views); what the major intellectual divisions of a resource are (table of contents, chapter, musical movement); identification of different views (double-page spread, cover, detail); the extent (in files, pages, or views) of a resource and the proper sequence of files, pages and views; as well as different technical (file formats, size), visual (pre- or post-conservation treatment), intellectual (part of a larger collection or work), and use (all instances of a resource in different formats--TIFF files for display, PDF files for printing, OCR file for full text searching) versions.

For digital reformatting of images, a fourth type of metadata is often used: technical metadata. Technical metadata is information that describes attributes of the digital image (not the analog source of the image) and helps to ensure that images will be rendered accurately. It supports content preservation by providing information needed by applications to use the file and to successfully control the transformation or migration of images across or between file formats. Technical metadata also describes the image capture process and technical environment, such as hardware and software used to scan images, as well as file format-specific information, image quality, and information about the source object being scanned, which may influence scanning decisions. Technical metadata helps to ensure consistency across a large number of files by enforcing standards for their creation. At a minimum, technical metadata should capture the information necessary to render, display, and use the resource. For digital images, the minimum required info is: MIMEType (ex. TIFF, JPEG), Byte Order, and Compression Scheme.

There are currently no universally accepted metadata standards. Some commonly used metadata standards include:

Dublin Core: A simple generic element set applicable to a variety of digital object types. At its most basic, the DC recommends a vocabulary of fifteen properties for use in resource description:
-contributor: the entity responsible for making contributions to the resource.
-coverage: topic of the resource
-creator: the entity primarily responsible for making the resource
-date: point or period of time associated with the resource
-description: an account of the resource
-format: the file format, physical medium, or dimensions of the resource
-identifier: an unambiguous reference to the resource within a given context
-language: language of the resource
-publisher: entity responsible for making the resource available
-relation: information about rights held in and over the resource
-source: resource from which the described resource is derived
-subject: topic of the resource
-title: name given to the resource
-type: nature or genre of the resource

Encoded Archival Description (EAD)-A set of rules for the representation of the intellectual and physical parts of archival finding aids. Often expressed in XML or SGML so that the information can be searched, retrieved, displayed, and exchanged.

Metadata Encoding and Transmission Standard (METS)-An XML schema for encoding structural metadata about compound objects, with placeholders for descriptive, administrative, and technical metadata.

MAchine-Readable Cataloging (MARC)--the standard library formatting method.

Hollas, Eric. (1997). Technical Standards and Medieval Manuscripts. In Proceedings of the Scholarly Communication and Technology Conference. University of California Press.

Liu, Yan Quan. (2004). Best Practices for Digitizing Library Materials. Online Information Review, 28(5), 338-345.