aDORe djatoka: An Open-Source Jpeg 2000 Image Server and Dissemination Service Framework

4th International Conference on Open RepositoriesThis presentation was part of the session : Conference PresentationsDate: 2009-05-19 03:00 PM – 04:30 PMThe JPEG 2000 image format has attracted considerable attention due to its rich feature set defined in a multi-part open ISO standard, and its potential use as a holy-grail preservation format providing both lossless compression and rich service format features. Until recently there was lack of an implementation agnostic (e.g., Kakadu, Aware, etc) API for JPEG 2000 compression and extraction, and an open-source service framework, upon which rich Web 2.0-style applications can be developed. Recently we engaged in the development of aDORe djatoka , an open-source JPEG 2000 image server and dissemination framework to help address some of these issues. The djatoka image server is geared towards Web 2.0 style reuse through URI-addressability of all image disseminations including regions, rotations, and format transformations. Djatoka also provides a JPEG 2000 compression / extraction API that serves as an abstraction layer from the underlying JPEG 2000 library (e.g., Kakadu, Aware, etc).  The initial release has attracted considerable interest and is already being used in production environments, such as at the Biodiversity Heritage Library , who uses djatoka to serve more than eleven million images. This presentation introduces the aDORe djatoka image server and describes various interoperability approaches with existing repository systems.  Djatoka was derived from a concrete need to introduce a solution to disseminate high-resolution images stored in an aDORe repository system.  Djatoka is able to disseminate images that reside either in a repository environment or that are Web-accessible at arbitrary URIs.  Since dynamic service requests pertaining to an identified resource (the entire JPEG 2000 image) are being made, the OpenURL Framework was selected to provide an extensible dissemination service framework. The OpenURL service layer simplifies development and provides exciting interoperability opportunities. The presentation will showcase the flexibility of this interface by introducing a mobile image collection viewer developed for the iPhone / iTouch platform

File-based storage of Digital Objects and constituent datastreams: XMLtapes and Internet Archive ARC files

This paper introduces the write-once/read-many XMLtape/ARC storage approach for Digital Objects and their constituent datastreams. The approach combines two interconnected file-based storage mechanisms that are made accessible in a protocol-based manner. First, XML-based representations of multiple Digital Objects are concatenated into a single file named an XMLtape. An XMLtape is a valid XML file; its format definition is independent of the choice of the XML-based complex object format by which Digital Objects are represented. The creation of indexes for both the identifier and the creation datetime of the XML-based representation of the Digital Objects facilitates OAI-PMH-based access to Digital Objects stored in an XMLtape. Second, ARC files, as introduced by the Internet Archive, are used to contain the constituent datastreams of the Digital Objects in a concatenated manner. An index for the identifier of the datastream facilitates OpenURL-based access to an ARC file. The interconnection between XMLtapes and ARC files is provided by conveying the identifiers of ARC files associated with an XMLtape as administrative information in the XMLtape, and by including OpenURL references to constituent datastreams of a Digital Object in the XML-based representation of that Digital Object.Comment: 12 pages, 1 figures (camera-ready copy for ECDL 2005

Evaluating the SiteStory Transactional Web Archive with the ApacheBench Tool

PDF of a powerpoint presentation from TPDL 2013: 17th International Conference on Theory and Practice of Digital Libraries, Valletta, Malta, September 22-26, 2013. Also available on Slideshare.https://digitalcommons.odu.edu/computerscience_presentations/1012/thumbnail.jp

Memento: Time Travel for the Web

PDF of a powerpoint presentation from the Web UNC Scholarly Communications Working Group Meeting, Chapel Hill, North Carolina, November 10, 2010. Also available on Slideshare.https://digitalcommons.odu.edu/computerscience_presentations/1020/thumbnail.jp

Scholarly Context Not Found: One in Five Articles Suffers from Reference Rot

The emergence of the web has fundamentally affected most aspects of information communication, including scholarly communication. The immediacy that characterizes publishing information to the web, as well as accessing it, allows for a dramatic increase in the speed of dissemination of scholarly knowledge. But, the transition from a paper-based to a web-based scholarly communication system also poses challenges. In this paper, we focus on reference rot, the combination of link rot and content drift to which references to web resources included in Science, Technology, and Medicine (STM) articles are subject. We investigate the extent to which reference rot impacts the ability to revisit the web context that surrounds STM articles some time after their publication. We do so on the basis of a vast collection of articles from three corpora that span publication years 1997 to 2012. For over one million references to web resources extracted from over 3.5 million articles, we determine whether the HTTP URI is still responsive on the live web and whether web archives contain an archived snapshot representative of the state the referenced resource had at the time it was referenced. We observe that the fraction of articles containing references to web resources is growing steadily over time. We find one out of five STM articles suffering from reference rot, meaning it is impossible to revisit the web context that surrounds them some time after their publication. When only considering STM articles that contain references to web resources, this fraction increases to seven out of ten. We suggest that, in order to safeguard the long-term integrity of the web-based scholarly record, robust solutions to combat the reference rot problem are required. In conclusion, we provide a brief insight into the directions that are explored with this regard in the context of the Hiberlink project