Rome Wasn't Digitized in a Day - Council on Library and Information ...

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manuscript pages and the transcriptions of the text are available for download onl<strong>in</strong>e. 50 Scholars are
work<strong>in</strong>g with digital images rather than the manuscript itself, and scholars from diverse discipl<strong>in</strong>es,
<strong>in</strong>clud<strong>in</strong>g palaeography, the history of mathematics and science, and Byzant<strong>in</strong>e liturgy, have done
extensive work with this palimpsest. Much of the image-process<strong>in</strong>g work with the palimpsest has
focused on develop<strong>in</strong>g algorithms to extract the text of Archimedes <strong>in</strong> particular from page images.
Salerno et al. (2007) used pr<strong>in</strong>cipal component analysis (PCA) and <strong>in</strong>dependent component analysis
(ICA) techniques to extract “clean maps of the primary Archimedes text, the overwritten text, and the
mold pattern present <strong>in</strong> the pages” from 14 hyperspectral images of the Archimedes. Their goals were
to provide better access to the text and to develop techniques that could be used <strong>in</strong> other palimpsestdigitization
projects. The authors also report that:
A further aspect of the problem is to partly automate the read<strong>in</strong>g and transcription tasks. This
cannot be <strong>in</strong>tended as a substitution of the human experts <strong>in</strong> a task where they perform better
than any presently conceivable numerical strategy, but as an acceleration of the human work
(Salerno et al. 2007).
The importance of not replac<strong>in</strong>g expert scholars with systems but rather of develop<strong>in</strong>g tools that assist
them <strong>in</strong> their traditional tasks is a theme seen throughout the literature.
Other significant work <strong>in</strong> the area of provid<strong>in</strong>g access to fragile manuscripts has been conduced by the
EDUCE (Enhanced Digital Unwrapp<strong>in</strong>g for Conservation and Education) Project. 51 Investigators on
this National Science Foundation–funded project have been work<strong>in</strong>g to develop systems that support
the “virtual unwrapp<strong>in</strong>g and visualization of ancient texts.” Accord<strong>in</strong>g to their website:
The overall purpose is to capture <strong>in</strong> digital form fragile 3D texts, such as ancient papyrus and
scrolls of other materials us<strong>in</strong>g a custom built, portable, multi-power CT scann<strong>in</strong>g device and
then to virtually “unroll” the scroll us<strong>in</strong>g image algorithms, render<strong>in</strong>g a digital facsimile that
exposes and makes legible <strong>in</strong>scriptions and other mark<strong>in</strong>gs on the artifact, all <strong>in</strong> a non-<strong>in</strong>vasive
process.
Some of the EDUCE Project’s image-process<strong>in</strong>g techniques have been used by the Homer Multitext 52
Project as described by Baumann and Seales (2009), who presented an application of imageregistration
techniques, or the “process of mapp<strong>in</strong>g a sensed image <strong>in</strong>to the coord<strong>in</strong>ate system of a
reference image,” to the Venetus A manuscript of the Iliad used <strong>in</strong> this project. The Homer Multitext
Project <strong>in</strong>cluded 3-D scann<strong>in</strong>g as part of its digitization strategy, but as the 3-D scann<strong>in</strong>g system
acquired un-textured 3-D models a “procedure to register the 2D photography to the 3D scans was
performed periodically.” Dur<strong>in</strong>g one photography session it was discovered that technical issues had
produced a number of images of poor quality. While these images were reshot, time constra<strong>in</strong>ts
prevented perform<strong>in</strong>g the 3-D geometry capture for these pages aga<strong>in</strong>. The result was a number of
folios that had two sets of data—a “dirty” image that had registered 3-D geometry and a “clean” image
with no associated geometry—to which the project wished to apply digital flatten<strong>in</strong>g algorithms. The
ma<strong>in</strong> computational problem was thus to determ<strong>in</strong>e a means of obta<strong>in</strong><strong>in</strong>g a “high-quality deformation
of the ‘clean image’ such that the text was <strong>in</strong> the same position as the ‘dirty image’” that would then
allow them to “apply digital flatten<strong>in</strong>g us<strong>in</strong>g the acquired correspond<strong>in</strong>g 3D geometry.”
50 http://archimedespalimpsest.net/
51 http://www.stoa.org/educe/
52 http://chs.harvard.edu/wa/pageRtn=ArticleWrapper&bdc=12&mn=1169