Operational Alexandria Digital Library
  Operational ADL
Introduction to ADL Metadata

This document will help you get started adding your collection to the Alexandria Digital Library (ADL). A collection in ADL consists of a geographically referenced set of items (maps, aerial photographs, satellite images, recordings, etc.), which has:

  1. Item level metadata - item-level information including an identifier that is unique within the collection
  2. Collection level metadata - a standardized description about the collection

Collection level metadata (CLM) is an integral part of the ADL webclient interface and middleware.  CLM can assist users in determining how applicable the contents of a collection are to a project by providing simple summary information such as title, scope, purpose, and responsible party, as well as aggregated information about the collection such as item counts by format and object type and histograms describing the spatial and temporal coverage.  The collection developer must always supply the simple summary information but the ADL software will generate the aggregated information automatically in the near future.  The summary information information can be collected/created even before you are ready to load your collection into ADL.  Review the ADL Metadata example to see the required and optional  information that you will need to provide in your CLM.

ADL collection level metadata is an XML document that has been rendered into HTML for readability.  The ADL Collection Metadata DTD (XML Document Type Definition) formally defines the semantics of the CLM.   You may view an example of CLM rendered in HTML as it appears in the ADL webclient. The spatial and temporal coverage histograms and item counts for the example are based on statistical scripts that are not automated at this point.

Once you have your CLM in XML and HTML files, place them in a web accessible directory (e.g. where your local collection data is/will be located).  For further detailed information on installing metadata files in ADL, please see: Instructions for installing local collections in the ADL Web Application

Thus, ADL has specified a content standard and XML encoding for CLM.  By contrast, collection developers are generally free to use any item level metadata, the only requirements are:
1. Item level metadata must be mapped to the ADL search buckets and standard metadata views (see example below)
OR you can submit your Item level Metadata in a table created according to the guidelines of the ADL Buckets - General Schema.

2. Each item must have an identifier that is unique within the collection.  Please see important notes about unique identifiers.

The ADL search bucket framework provides a uniform view of the library and provides the elemental items that are aggregated and collated into statistical summaries and histograms in the CLM for the benefit of clients and the collection discovery service.  Please review the example metadata, schemas and field definitions in the ADL Metadata example section.

Continue to ADL Collection Level Metadata example