Digital archiving of cultural heritage has heretofore focused on capturing accurate color information via spectral imaging. We review a means of capturing topographical information entitled reflection transformation imaging. This paper discusses an experiment that attempts to merge these two techniques. Several paintings were imaged and color accurate, interactive texture maps were generated. Experimental deficiencies are identified and suggestions are made for remediation. A new dual-imaging technique with improved capability is discussed. Our conclusion is that the simultaneous capture of high-accuracy spectral and textural information is entirely feasible.

The PDF/A specification for long-term preservation of electronic documents became an international standard in 2005. This standard seeks to guarantee the long-term visual appearance of an electronic document. For collections to be archived as PDF files, it makes sense to select the PDF/A file format, because this particular type of PDF file makes it easier to migrate to future file formats. However, in the years before the PDF/A specification became a standard, many organizations began creating archives of collections in PDF, but in formats not necessarily compatible with PDF/A. Because of its value to preservation that PDF/A offers, there is an advantage to migrating collections to PDF/A. Commercial software tools are becoming available, both for creating PDF/A files and for evaluating their compatibility with the PDF/A standard. One such tool was used to study PDF files culled from the Internet as well as from an in-house collection to determine the chances of success for migrating an archived collection of PDF documents to PDF/A. This study explores the types of problems posed by such a migration, and determines the circumstances in which a migration would be successful.

This paper begins with the transition from analog to digital photography, and the expanding role of the now digital museum photographer. The problems of color accurate digital image capture of art and artifacts are discussed, and a simple method using readily available tools to calibrate monitors, profile cameras, and adjust the profiles to obtain color accurate RGB files is presented.

The development of digital collections has benefited from both the technology and price-volume advantages of the wider digital imaging markets. With the advent of web-based delivery, standard file formats, and metadata, however, have come a host of technology related choices and concerns about variability and compatibility. We suggest ten simple principles that can be used to increase utility and reduce variation of the digital image content for most collection projects.

In the future, appropriate analog materials are or will not be available for reformatting historical photographs, and digitization will become a common approach for all preservation reformatting. This paper will provide an overview of a range of technical issues and imaging approaches that should be considered when planning to use digitization for preservation reformatting.This paper is the result of work done by experts who first met in April of 2005 to begin an effort to draft guidelines for preservation reformatting of photographs using digitization. The aim of the meeting was to convene a high-level set of practitioners, with a best practices document and possible tools for implementation as potential eventual outcomes. One priority was to address gaps in specific technical areas and work towards developing consensus within the broader community on appropriate approaches for digitizing photographs, including capture device performance, tone and color reproduction, spatial and signal resolution, etc. Discussions centered around characteristics and properties of originals, what essential characteristics need to be maintained for preservation purposes, big-picture tradeoffs between technical quality, longevity, affordability, functionality, sustainability, commitment to maintain resources, etc., and the differences between “practical” approaches (done today with existing equipment) and “ideal” approaches (highest information capture possible and the scientifically best methods of imaging).The outcome of the meeting is a draft framework defining five information capture levels (Current Practices - basic, intermediate, advanced, and Emerging Practices – basic and new approaches) for preservation digitization of photographs. Each level represents a significant increase in the amount of information captured, an increase in the accuracy of the information, and a shift to alternate image states and new technical approaches. Specific technical parameters are addressed for each level, including source assessment, capture device performance, image state (output or input referred), imaging environment, color mode and encoding, signal and spatial resolution, rendered tone reproduction, rendered density range, colorimetry, quality control, compression, and image processing. This paper will provide an overview of the concepts and specifics developed as a result of these activities.

Two topics that have been prominent at recent IS&T Archiving Conferences have been OAIS and JPEG2000. OAIS stands for Open Archival Information System; JPEG2000 is a wavelet-based image compression standard from the JPEG committee. While use of JPEG2000 is growing in image archiving systems, its use is seldom described in the context of the OAIS model. This paper will describe the use of JPEG2000 in the context of the OAIS Information Packages and their requirements. It will report on the practical use of JPEG2000 data and files in an OAIS-based image archiving system, with a special focus on the choices made for JPEG2000 content in the Archival Information Package (AIP), and how they affect downstream performance when content is disseminated to the consumer in the OAIS model in the form of a Dissemination Information Package (DIP). The encoding parameters can affect both the ability of the AIP to meet the requirements of the archival system and the efficiency of the transformations between AIPs and DIPs, especially when the DIPs are not precomputed but derived on demand to meet consumer requests.

The current and projected costs of storage are a critical issue as organizations face an explosive growth in data. While the cost of purchasing storage hardware is readily available from vendors, there is little published literature that describes the total cost of providing storage from an operational perspective. This paper describes current estimates of both disk and tape storage based on operational experience at the San Diego Supercomputer Center which operates a large-scale storage infrastructure. These costs include not only the storage hardware costs, but also the costs of supporting servers and related infrastructure, hardware maintenance, software licenses, floor space, utilities and labor costs. A brief discussion of projected cost trends in both disk and tape is provided, as well as a comparison to current web-based commercial storage services.

Rapid technology advancement and obsolescence present a constant challenge for preserving digital objects in a digital repository system. To ensure the long-term preservation of archival content, DAITSS, a digital repository system developed for the Florida Digital Archive, implements a scheme to automatically identify, validate, characterize and transform the format of digital objects in its repository. This scheme purposes to fulfill the unique requirements of the Florida Digital Archive.

The quality, fitness for purpose, and cost of digitized microfilm images and their accompanying metadata (or indeed any outsourced analog or digital product) are typically specified by contractual arrangements with vendors, who are then free to produce conforming deliverables in any manner they see fit. Given this degree of freedom accorded vendors with respect to digital image and metadata production, it becomes essential that the vendor and its library, archive, or museum clients be able to demonstrate that conformance to contracted specifications is (a.) achievable given the technology available to the vendor or in the technology marketplace, and (b.) that it has been achieved with the deliverables at hand.To support a process control and quality improvement process that results in a mission-critical degree of assurance among libraries, archives, museums, and the vendors who provide microfilm digitization services, and to provide a model that interested parties in the Cultural Heritage community can study and improve upon, a series of statistical studies of the microfilm digitization process is being undertaken. The studies begin by modeling the entire microfilm digitization process as a series of coordinated steps – with newspaper issues and reels of microfilm as inputs and outputs – that result in the production of digital images of specified quality. The inputs or outputs of selected steps in the microfilm digitization process are then chosen for their importance to the process as well as their being amenable to qualitative or quantitative measurement.The final result of the processing steps – a digital image – is intended to serve purposes that will be dependent on characteristics of the digital image. Casual or close reading, examination of newspaper typeface characteristics and paper textures or color, and the location of textual passages using full-text indexing can be found to require images of differing spatial and tonal resolution. In order to predict during the production process the fitness of a digital image of a microfilm frame for the purposes intended by a Cultural Heritage institution, it will be necessary to determine whether there exists a predictable relationship between the measured or judged quality of the original materials, its microfilmed images, the digital image and the outputs of selected production steps that lead to the creation of the digitized image.With improved predictability of digital imaging outcomes, opportunities therefore exist for identifying and eliminating undesirable digitization process variation – and for introducing corrective process steps for managing printed materials that are determined to be (via a human judgment or a mechanical measurement step) damaged or otherwise reduced in quality. Before this level of understanding and control of a digital imaging process can be achieved, characterization of all critical steps in the processing chain must occur, so that their effects on the quality of the resulting digitized images can be appreciated.This first study involves gaining an initial indication of the imaging capabilities and range of normal variation of commonly used microfilm digitization devices and their associated imaging practices independently of the physical characteristics of any microfilm reel that will be digitized. With the capabilities and range of variation of the imaging devices known, the characteristics and range of variation of the microfilm materials themselves can then be determined. With this knowledge, three possibilities present themselves: the ability of a quality monitoring regime to detect genuine variation in the digitization process can be estimated; the benefits of improving specific aspects in the digitization process – notably improvements in imaging devices and imaging practices – can be determined; and the upper limi ts of quality-related and quality-limited deliverable characteristics such as OCR accuracy and judged/printed newspaper image quality can then be established.This first study reports on the collection and analysis of quantitative measures of image quality made using standardized testing materials supplied to vendors who provide microfilm digitization services to the Cultural Heritage community.The results of the first study indicate that additional training may be needed to establish a proper understanding (among management and production staff alike), acceptance, and execution of quality control procedures such as device characterization, the use of targets during actual production, corrective and preventive action, automatic and/or manual recordkeeping, and the like. Also indicated is the need for digitization technology manufacturers and the vendors who use their products to participate in the quality control process by collecting and providing device characterization data as well as by designing in product features that simplify the collection of quality control data.

The Future Digital System (FDsys) is a digital archive being developed by the U.S. Government Printing Office and Harris Corporation. It will provide permanent public electronic access to authentic government publications via a web interface. The FDsys is being designed based on the Open Archival Information Systems (OAIS) reference model. The OAIS model incorporates many archiving best practices and increases the chance for developing a successful archive that will protect and preserve content over the long term. Applying the OAIS reference model requires making many engineering decisions about how to apply the model to a particular archive's mission and operations. This paper describes the specifics of how the information packaging concepts of the OAIS model are being applied to FDsys to address the archiving problems of storing complex (compound) digital objects, managing multiple renditions of the same publication, preserving publications over time, managing access rights to publications, and maintaining a record of the history of a publication within the archive. How information is packaged within a digital archive is critical to the success of the archive. This paper provides a look at the design of a large digital archive and a concrete example of how some important aspects of OAIS are being applied.