NIMA, a new agency formed by combining the Defense Mapping Agency and the Central Imagery Office, provided $150K of funding support for research into metadata issues. This research will focus mainly on three problems: (1) catalog access and image access in terms of the Standards Profile for Imagery Access, involving use of various API's; (2) generation of metadata from metadata, and issues of information inferable from metadata; (3) evaluation of various items, such as the VPF successor to DCW, in relation to the Alexandria atlas subproject.
In August 1996 the Implementation Team contracted with the National Imagery and Mapping Agency (NIMA) to prototype distributed image access services based on the Common Object Request Broker Architecture (CORBA). Specifically, we are using our existing catalog database to test NIMA's Image Access Service (IAS) specification, as specified in CORBA's Interface Definition Language (IDL). We will report to NIMA on implementability and functionality of IAS specification.
At the same time the collaboration will expose ADL to the issue of distributed catalog services, particularly as implemented in a CORBA environment. After evaluating several popular CORBA development packages (Xerox ILU; Digital ObjectBroker; Visigenic VisiBroker; Iona Orbix), we installed Digital ObjectBroker in December 1996. Our CORBA development is now progressing on two fronts:
We also devote a significant effort to tracking the evolution of the IAS specification and coordinating our activities with NIMA. We expect to complete the initial IAS prototype in April 1997.