The Digital Assets Repository (DAR) is a system developed at the Bibliotheca Alexandrina, the Library of Alexandria, to create and maintain library's digital collections. DAR acts as a repository for all types of digital material, thus preserving and archiving the digital media as well as, providing public access to digitized collections through a web-based search and browsing facilities.

    The goal of this project is building a digital resources repository by supporting the creation, use, and preservation of a variety of digital resources, as well as the development of management tools. These tools help the library to preserve, manage and share digital assets. The system is based on evolving standards for easy integration with web-based interoperable digital libraries.

    One of the main issues in designing digital libraries is the association of the digital content with its metadata, such that indexing, browsing, searching and retrieval can be done efficiently. The metadata attached to the objects is also used by the system to provide guided search for users by displaying related objects e.g. objects that have same creator or that fall under the same subject heading. This linkage between objects provides the user with a rich search experience and facilitates the exploration of the repository contents based on the user's interests. 

    Over 115,000 books are now available on DAR's website. For books that are out-of-copyright, their contents are fully available on the Internet. For books that are in copyright, Internet users can browse only 5% of the book, with a minimum of 10 pages. However, all the books are digitally available inside BA. Further more, for in copyright books, the publishing module allows simultaneous access to the number of books purchased by BA only to intranet users. That is, if BA has purchased two copies of a book, only two users can access the digital copy simultaneously. Only when one of them releases the book, another user can have access to it.

    Moreover, a digital Book Viewer has been developed for displaying the books based on the image-on-text technology. In addition, research was carried out in co-operation with Arabic OCR producers in order to achieve efficient, high quality recognition for mass OCR production for Arabic content, reaching an accuracy ranging from 90% to 97%. Although the accuracy is not high enough to allow users to read the output of the OCR, it is good enough for searching.

    Therefore, BA has concentrated its efforts into publishing books using the text layer behind the image, to allow for searching the text while exposing the image to the user. The content-based search is performed on the whole collection of available books, whether in copyright or out-of-copyright, while viewing the actual book is restricted for in copyright books on the Internet.

    DAR is also concerned with the digitization of material already available in the library or acquired from other research-related institutions. A digitization laboratory was built for this purpose at the Bibliotheca Alexandrina. The lab is equipped with the state- of- the- art technologies for digitizing different types of material, including slides in multi formats, negatives, books, manuscripts, pictures and maps, audio and video.

    The complete cycle of the workflow to produce digital objects has been automated and integrated with the BA Library Information System.

For more info :http://dar.bibalex.org/#HomePage