Digitization Information, Standards:
Data Gathered by Robert Kraft for report at SBL/CARG session
24 November 1998, Orlando FL
 

Some Issues for Consideration:

Are there special needs in CARG areas of interest that call for 
  special standards? 
If so, how flexible will the standards need to be?

Examples:
  Manuscript studies (lexicography, paleography, textual criticism, etc.)
  Archaeological data (inscriptions, objects, architecture, plans, etc.)
  Photographs and Art (reproductions)
  Images in motion
  
Levels of desired standards:
  Imaging (creating the digitized materials)
  "Metadata" (descriptive records of processes used, etc.)


Some Convenient Links to Relevant Materials:

Jay Treat's resources page at CCAT (UPenn)
http://ccat.sas.upenn.edu/hot/mss.html 

The ABZU page for Papyri at Chicago
http://www-oi.uchicago.edu/OI/DEPT/RA/ABZU/ABZU_REGINDX_EGYPT_PAP.HTML

The Labyrinth page for MSS at Georgetown
http://www.georgetown.edu/labyrinth/subjects/mss.htm

Time & Bits: Managing Digital Continuity
Getty Conservation Institute - Getty Information Institute - 
  The Long Now Foundation
http://www.gii.getty.edu/timeandbits/links.html
[from a library and art history perspective, lots of information]

See also the Special Issue on the Use of Computers in the Study 
of Ancient Documents in Literary & Linguistic Computing  
[= L&LC]12.3 (1997) 



Some Relevant Projects (index to more detailed sections that follow):

01. APIS = Advanced Papyrological Information System Proposal (1994)
http://odyssey.lib.duke.edu/papyrus/texts/APISgrant.html
[standards for the major joint papyrological project]
[camera, 600 dpi, TIFF & JPEG storage; 150/72 dpi GIF displays]

02. Cairo Geniza Project at Cambridge ENG
http://www.lib.cam.ac.uk/Taylor-Schechter/GOLD/digital.html
[notes on procedures used for this pilot project on Hebrew MSS]
[camera, 300 dpi/24 bit, JPEG delivery & storage] 

03. CSAD = Centre for the Study of Ancient Documents (Alan Bowman, Oxford)
alan.bowman@christ-church.ox.ac.uk
http://www.csad.ox.ac.uk/CSAD/Images.html#images
[initial focus on inscriptional materials at 150/300 dpi]

04. The Perseus Project
http://www.perseus.tufts.edu/
gcrane@emerald.tufts.edu
[various types of digitization in interaction with ancient texts]

05. Thesaurus Musicarum Latinarum (TML)
http://www.music.indiana.edu/tml/tmlintro.htm
[a major project on Latin Music Theory, uses GIF format]

06. Bodleian Library, Oxford
Towards an Image Catalogue . . . 
http://www.rsl.ox.ac.uk/imacat.html
[images from slides of MSS; pilot project using JPEG & GIF]

07. Digital Scriptorium, University of California at Berkeley
http://sunsite.berkeley.edu/Imaging/
[proposed standards for digital libraries; outlines issues]

08. The Art Museum Image Consortium (AMICO)
http://www.amico.net/docs/dataspec.final3.shtml
[a major cooperative museum initiative]
[1024 x 768 pixels, 24 bit color; uncompressed TIFF format]

09. Relationship to the Text Encoding Initiative
http://lcweb.loc.gov/catdir/semdigdocs/hockey.html
[some notes on "metadata" treatment by Susan Hockey]

09.1 TEI and XML in Digital Libraries
http://www.hti.umich.edu/misc/ssp/workshops/teidlf/teigrp3.html 

10. SURVEY ON PHYSICAL PREPARATION OF MATERIALS TO BE DIGITIZED
http://www.rlg.org/preserv/joint/index.html
[a recent conference to discuss these matters; results forthcoming]


---
01. APIS = Advanced Papyrological Information System Proposal (1994)
http://odyssey.lib.duke.edu/papyrus/texts/APISgrant.html

See also Roger Bagnall, "Imaging of Papyri: A Strategic View," in 
L&LC 12 (1997) 153f.

(c) Images of the documents. The APIS partners have as part of 
their preparations for this application conducted a study of 
digital imaging technology, funded by the Commission on 
Preservation and Access, the report of which is included here as 
Appendix 8. The conclusions of this study are that true 600 dpi 
imaging through digital cameras (not flatbed scanners) is an 
appropriate minimum standard for images. For views of the 
entirety of large documents, 300 dpi images will be included, but 
600 dpi or higher images of portions of the original. 
Papyrologists using these images, with the advantage of modern 
computer tools for text reconstruction, have consistently found 
them much more valuable than traditional photographs, either in 
black and white or in color, and 600 dpi provides sufficient 
resolution and color accuracy for almost all purposes. Some 
papyri or parts of papyri with exceptionally dense information 
will be captured at higher resolution. In Appendix 8 we detail 
the standards for file format and other pertinent aspects of the 
imaging that we will adopt. These standards, which are in line 
with industry standards and projects like the Vatican Library 
Project, will make images fully interchangeable among the 
institutions involved and allow ready consultation over the 
Internet. 

In the case of relatively small papyri, our study concluded that 
600 dpi imaging was feasible with existing digital cameras, and 
that such cameras would produce imagery that would never need 
replacing. For larger papyri, however, it is not clear that 
future advances in imaging technology will not bring considerable 
advantages. For papyri over the size of 17 x 25 cm, therefore, we 
will also produce 4x5 color photographic transparencies. 
Experience in reproducing paintings and other fine arts has shown 
that these are sufficient to allow retaking of digital imagery as 
the capabilities of the latter improve. 

APIS will also eventually make use of multi-spectral imaging 
(MSI), a technology developed at the Jet Propulsion Laboratory 
(Pasadena) and applied to some Dead Sea Scrolls fragments with 
considerable success. MSI uses bandwidths in the extreme infrared 
to bring out writing by identifying what part of its spectral 
signature is unique to it and extracting that bandwidth. This 
technology also uses a digital camera, but with a special lens 
designed for sampling the spectrum at specified intervals of 
bandwidth. At present, MSI is still a rapidly developing 
technology, and the cameras that use it are not interchangeable 
with those supporting the standard color imaging already 
described. It is also useful only for that minority of papyri 
(and, importantly, ostraca, where contrast is often poor) where 
there are significant difficulties in bringing the writing out 
from the background. APIS plans to bring MSI into use in Phase 2, 
after the materials on which it will be used have been 
identified; at present it is impossible to estimate on what part 
of the collections it would be applicable.[7] 

All of the collections have existing bodies of photographic 
negatives made for various purposes in the past, and these will 
be scanned at an early stage. Michigan also has many photographs 
of texts once there but now returned to the Egyptian Museum in 
Cairo, and these photographs can also be digitized and included. 
Ultimately the vast resources of the International Photographic 
Archive of Papyri (centers in Brussels, Cologne, Oxford, and 
Urbana) can be drawn on as APIS grows beyond the original six 
collections. The project will need to resolve intellectual 
property issues connected with images when a wider range of 
repositories is included, particularly because it will not be 
possible to impose any standard policies about matters like 
publication permission on foreign institutions that adopt our 
standards. 

---
01.1 From John F. Oates' Progress Report 1998
http://odyssey.lib.duke.edu/papyrus/texts/report.html

B. IMAGES

Each text contains a field through which on-line images can be 
accessed, where they exist. Links to numerous published texts are 
in place (from P.Bad. II, IV, VI, P.Carlsberg, P.Koeln VIII, 
P.Tebt. I, II, III 1, P.Oxy. LIX. Some of these images also 
provide links to the Greek texts in the DDBDP. This is an obvious 
locale where a gateway page on an APIS Web site can be of great 
use in facilitating the use of image and text together. 

--- 
01.2 Imaging the Duke papyri
by Peter van Minnen 
http://odyssey.lib.duke.edu/papyrus/texts/imaging.html

In the course of the first year of the project it was decided to 
make digital images of the papyri instead of photographs or 
slides. The advantages of making digital images directly from the 
originals seemed obvious at the time. The imaging could be done 
in-house, the images would preserve the dimension of depth as no 
photograph would, they would allow manipulation afterwards, which 
could serve research as well as teaching, and they could be 
shared with other institutions over the internet. The imaging 
would de done in the second year of the project by the librarian 
hired for the purpose in addition to making catalogue records. It 
was expected that this would entail an extension of the project 
with a third year, but this seemed also indicated by the amount 
of time it would take the papyrologist to deal with the remaining 
number of papyri. 

For the imaging a flatbed color scanner was bought in September 
1993. Color was deemed superior to grayscale, especially since 
the images were supposed to provide the archival backup to the 
collection. Using color would of course increase the size of the 
files. The scanner bought was a UMAX 800, a 24-bit scanner that 
allowed scanning up to 800 dpi. A digital camera was considered 
too expensive at the time. It was not even clear whether reliable 
digital cameras were already available commercially. The 
financial advantages of a flatbad scanner over a digital camera 
were more important than the disadvantages: the lack of a light 
source behind the papyrus to light up holes and the clumsiness of 
scanning upside down. Since the Duke papyri would be scanned 
after they were framed, however, the last-mentioned disadvantage 
seemed trivial. 

Experience has shown that scanning through glass has another 
disadvantage. The effect of the glass on the registration of 
color by the scanner is quite noticeable. This also goes for 
using a digital camera on papyri framed in glass. During the 
first year of the scanning project the color spectrum of the 
scanner was not calibrated. The color of the scans was corrected 
manually and only approximates the colors of the originals. The 
second year, a special calibration tool was purchased that goes 
some way to correct for the glass, but it turned out to be 
unavoidable to manually correct the scan. Taking papyri out of 
the frame for scanning purposes would not be feasible for those 
papyri that consist of multiple fragments or are too fragile to 
handle upside down. Scanning unframed papyri seems impossible if 
it is done by an outside vendor. 

Originally it was not clear whether potsherds, wooden boards and 
lead tablets could be scanned at all, but these three-dimensional 
objects posed no problem. Their surfaces are after all rather 
smooth. It is the fibrous structure of the papyrus itself that 
turned out most difficult to capture electronically. The UMAX 800 
proved better at it than some other flatbed scanners, but it has 
been replaced in October 1995 with a Sharp JX-330, which scans 
much faster and records colour more accurately than the "old" 
UMAX 800. The angle of the light source used inside the scanner 
determines how the fibres will show up on the scan. The scanner 
reads the image in three times and corrects it as it goes along. 

The computer used for the scanning is a Macintosh Quadra 800 with 
1GB of memory, 32MB of RAM and a 24-bit color video card. An 
accelerator board (Storm) was also installed. The program used to 
generate the scans was Adobe PhotoShop version 2.5, later version 
3.0. This seemed quite adequate for both the production of the 
scans and the use of the images in research and teaching. As a 
backup digital tape(s) are used as well as an external hard drive 
(DataStor), acquired in February 1995. When the project is 
finished the tapes with the archival scans will be kept available 
at Duke through the computing center. The derivatives will be 
stored on a server and remain universally accessible in 
combination with the catalogue records and other supporting 
materials. 

Originally the color scans were made at 300 dpi, but after about 
one year of experimenting this was raised to 600 dpi. This would 
create much larger files, but the cost of storage media is 
dropping fast. The Advanced Papyrological Information System, an 
undertaking of several American universities holding substantial 
collections of papyri (Columbia University, Duke University, 
Princeton University, The University of California at Berkeley, 
The University of Michigan, and Yale University) has adopted 600 
dpi as the standard for digital images of papyri. The reason for 
using 600 dpi is simple: to read original papyri papyrologists 
currently use microscopes that enlarge 4x, 5x, 7x or 10x; 600 dpi 
images can be blown up 8x on a 72 lpi screen, the kind most 
commonly in use today. With a digital camera a consistent 600 dpi 
rate can be achieved by keeping the camera at a fixed height on 
its stand. 

It was decided early on to adjust the quality of the image 
through a minimum of manual operations. The color of the scans is 
off for reasons stated above and this needs to be corrected in 
the archival scans. To this end the histograms have been 
manipulated minimally through Adobe PhotoShop. To increase the 
contrast of the writing, the most important consideration for 
specialists, the target audience most likely to use the archival 
scans, the unsharp mask function has been applied consistently. 

The data are saved in different formats. The archival master set 
consists of 600 dpi scans stored in TIFF with LZW compression. 
Another set of 600 dpi scans are stored with JPEG compression. 
These scans will be used in research and teaching at Duke and at 
other institutions on request. Two derivatives are made of each 
600 dpi scan: a 150 dpi and a 72 dpi scan. Both are stored in GIF 
and made available over the internet. The relatively small file 
sizes should cause no problem. The 72 dpi scan will show up life-
size on a viewer such as Netscape using a 72 lpi screen. The 150 
dpi scan will show up twice enlarged or can be blown up to twice 
its size, which allows the more difficult scripts to be read with 
ease. But even the 150 dpi scans will not provide enough detail 
to deal with problem spots. This will, however, only be a problem 
for specialists interested in a particular papyrus, and they can 
always request a copy of the 600 dpi scan. It seemed more 
serviceable to all parties concerned (specialists and non-
specialists) to have images of all Duke papyri available for 
quick consultation all the time. 

A review of a book on the application of digital technology to 
ancient manuscripts such as the Dead Sea Scrolls appears in the 
Bryn Mawr Classical Review. 

A more technical description of digitizing papyri has been 
prepared by a team of Finnish scholars working on the carbonized 
papyri from Petra in Jordan. 
 http://www.cs.hut.fi/papyrus/

"Recording, Processing and Archiving Carbonized Papyri"
 Antti Nurminen, 34044T, andy@cs.hut.fi
TABLE OF CONTENTS 
   1.Abstract 
   2.Introduction 
        1.Papyrus 
        2.Digitizing Images 
        3.Image Processing 
        4.Hypermedia 
   3.Related Work 
   4.Recording Carbonized Papyri 
        1.Measurements 
        2.Experimental Setup 
        3.Photography and Photo Lab Work 
             1.Illumination 
        4.Scanning Photographs 
        5.Direct Digitizing 
   5.Miscellaneous Imaging Methods 
        1.Thermographic Imaging 
        2.X-ray Imaging 
        3.Stereographic Imaging 
        4.Live Video Recording 
   6.Image Processing 
        1.Image Analysis 
             1.Histograms 
             2.Profiles 
        2.Image Processing Tools 
             1.Image Thresholding 
             2.Histogram Modification 
             3.Edge Detection 
             4.Noise Reduction 
             5.Deviation Method 
             6.Papyrus Structure Elimination 
             7.FFT Filters 
             8.Miscellaneous Viewing 
        3.Combinations of Digital Filters 
   7.Digital Image Archiving with Hypermedia 
   8.Conclusions 
   9.Acknowledgements 
  10.References
See also D. Obbink, "Imaging the Carbonized Papyri from Herculaneum,"
L&LC 12 (1997) 159-62.

Another application of digital technology to the study of Demotic
papyri has been described in a congress paper by Janet H. Johnson.
http://www-oi.uchicago.edu/OI/PROJ/DEM/PUB94/CGP/CGP.html

COMPUTERS, GRAPHICS, AND PAPYROLOGY
By Janet H. Johnson, Professor
The Oriental Institute
The University of Chicago
(This article originally appeared in Proceedings of the 20th 
International Congress of Papyrologists Museum Tusculanum, 
Copenhagen 1994, pp. 618-620, and is made available 
electronically with the permission of the editor. 

01.3 APIS at University of Michigan
http://www.hti.umich.edu/a/apis/ (technical specs)

See also Trianos Gagos <traianos@umich.edu>
"Advanced Papyrological Information System (APIS): The Michigan
Experience," Literary and Linguistic Computing 12.3 (1997) 155-57.

2.  Specific guidelines for the full-size image

-- If there is any writing on the verso, make a full-size image 
of the entire surface in order to register the position of the 
writing on the surface (the 600 dpi image will capture only the 
close image). Make note of all verso files that are captured in 
the imaging process, but have not found their place in the 
publication. This can be done in the FileMaker Pro database 
field, called 'side section', e.g.  r/v (PMich has recto only). 

3.  Specific guidelines for the 600 dpi images:

-- one must assure sufficient overlap, otherwise (especially with 
curving and uneven lines) one might miss information. The minimum 
amount of overlap should be one line on the horizontal axis and 
two words on the vertical axis.  Ideally, cropping should be done 
along word-ends. 

-- cropping becomes a complicated issue with images 10x12" and 
larger which consist of 4+ tiles. One must make sure that the 
tiles are of equal size which can be done by keeping the previous 
image on the screen while cropping. ( Tiles of inv.  281 are left 
uneven).  Make sure that cropping is done along the same 
horizontal line and tiles can be matched up easily. 

-- when there are big gaps in the papyrus (half of left margin 
missing, e.g. 281 or gap in the middle) one should photograph the 
empty space as well, because it can be important for making 
conjectures. 

-- the technique for photographing a missing part of a left 
margin is as follows. Align a ruler along the existing part of 
the margin and put a yellow post-it mark along the line to help 
determine the width of the empty space that needs to be included. 
If a part of the post-it note gets into the image, it can be 
easily cropped out. 

-- in the case of several lines on the verso, photograph only the 
portion containing the text. The thumbnail version gives the 
position of the writing on the surface. 

-- do not include ruler in 600 dpi images

-- the order in which the 600 dpi images were taken should be 
recorded in the imaging database.  The arrangement follows 
several patterns which can be expressed with a grid attached to 
each individual file and the type of arrangement recorded in the 
database. 

Advanced Papyrological Information System

Michigan Papyri On-line Catalogue

List and Description of Fields

LIST

I. Background & Physical Properties
Inv. No.
Section/Side
Publ./Side
Library
Location
Connections
Material
Items
Size
Lines
Mounted
Negative
Negative in Copenhagen
Conservation Status
Notes on Preservation
Palaeographic Description
Publication status

II. Contents
Date
Origin
Provenance
Acquisition
Language
Genre
Author
Type of text/title of work
Content
Subject headings
Persons
Geographica
Translation

III. Information on Publications
1st Publication: Editor, Series, Year, Pg/Nr., Photo
        SB; Corrections
Republication: Editor, Series, Year, Pg/Nr., Photo
        SB; Corrections
Further republication: Editor, Series, Year, Pg/Nr., Photo
        SB; Corrections
Bibliography
Assignments, date; research status
Electronic editor, date; revision history

Notes

III. System & Image Metadata
Image source
Image arrangement
Extent of the image
Full size front
Full size back
600 dpi front
600 dpi back
Availability/System requirements
Scanning Medium
Time to scan
Scanner initials
Creation of image
Institution
Date scanned

IV. Information on Cataloging
Cataloger initials
Date Cataloged
Check

Transliteration rules for place and person names.

---
02. Cairo Geniza Project at Cambridge ENG
http://www.lib.cam.ac.uk/Taylor-Schechter/GOLD/digital.html

Producing images

The images are obtained directly from the manuscripts. The 
digital camera is a Kontran Progres 3012, which has an Adobe 
Photoshop plug-in, which includes a calibration set-up. Adobe 
Photoshop is used for image manipulation. Colour matching is by 
eye. Sharpening is applied. Balance, contrast and brightness are 
adjusted by eye. 

The images are digitized at 300 dpi at 24 bits. Pixel detail is 
2400x3200x24 bits or 3200x2400x24 bits. The originals are stored 
at 95% quality, and the delivery images are JPEG encoded at 80% 
quality. 

The delivery formats of the images are JPEG or PNG, depending on 
the browser. The storage format is JPEG. The images are archived 
in an automated tape archive and on cd-rom. 

---
03. CSAD = Centre for the Study of Ancient Documents (Alan Bowman, Oxford)
alan.bowman@christ-church.ox.ac.uk
http://www.csad.ox.ac.uk/CSAD/Images.html#images

See also C.V.Crowther, "Imaging Inscriptions," and Alan Bowman et al.,
"Imaging Incised Documents," in L&LC 12 (1997) 163-176.

Building an Image Bank of Inscriptions

Aims

The imaging project for inscriptions developed out of an 
initiative to reorganise and catalogue Oxford University's 
squeeze collection and make it accessible as a research resource 
to the widest possible audience. The project draws its 
inspiration from the work undertaken at Michigan and Duke 
universities within the framework of APIS to create a unified 
database of papyrological resources including texts and, above 
all, images. 

Methods

The requirements of an image database of inscriptions differ from 
those of a papyrological image bank in a basic respect - 
inscribed documents are in general much larger than written 
papyri. This makes it both possible, while retaining the 
advantages of the digital medium, and, indeed, necessary, in 
order to keep image sizes within manageable limits, to capture 
images at a lower resolution than the 600 dpi archival standard 
prescribed by APIS for papyri. 

During the initial experimental stage of the project images are 
being captured at resolutions of 150 dpi and 300 dpi. 150 dpi 
images are more than adequate for most purposes, but, in order to 
ensure that the images in the database remain useful for as long 
as possible, it has seemed better to set the higher resolution as 
the standard to be used in the second phase of the project, when 
representative corpora of images begin to be built up. Images are 
taken directly from squeezes using UMAX Powerlook Pro and Mirage 
flatbed scanners and PowerMacintosh 8100 and G3 computers. Images 
of inscriptions larger than the scanning area are stitched 
together from separate scans made using the same settings. Minor 
adjustments for contrast are made in Adobe Photoshop 3.0. 
Photoshop's Unsharp Mask filter has been applied to the 
derivative sample images available from this page, but not to the 
original scanned images. Experiments at photographing squeezes 
have also been carried out using the Centre's Leaf Lumina digital 
camera, but, although the results were satisfactory, the flatbed 
scanner remains the preferred method of capturing images of 
squeezes. 

The primary images acquired for the database will be taken from 
squeezes. Because these are a secondary medium, the basic images 
contained in the image bank will necessarily be at least two 
stages removed from the originals that they represent. A squeeze, 
moreover, can represent only the inscribed face of an 
inscription. In a field of study in which mistakes can follow 
from inattention to the physical context and character of a 
document, these are potentially serious limitations to the scope 
of the database. Wherever possible, therefore, images of squeezes 
will be supplemented by photographs of the original monument. For 
studying the inscribed text itself, however, images of squeezes 
have considerable advantages, because they can be captured in 
controlled conditions and at a uniform scale. It is for this 
reason that they form the primary focus of the Centre's imaging 
project. 

The quality of the image will depend naturally on the quality of 
the squeeze, which, in turn, will reflect the preservation of the 
inscribed surface. The sample images presented here are all taken 
from good squeezes, but in the case of OGIS 78, although the 
result is very useable, the difficulties of representing severely 
eroded surfaces are beginning to become obtrusive. It may be that 
image enhancement techniques will eventually have to be used to 
provide acceptable representations of particularly difficult 
texts. This is an issue that is at present under consideration. 

---
04. The Perseus Project
http://www.perseus.tufts.edu/
gcrane@emerald.tufts.edu

---
05. Thesaurus Musicarum Latinarum (TML)
http://www.music.indiana.edu/tml/tmlintro.htm

INTRODUCTION TO THE THESAURUS MUSICARUM LATINARUM AND ITS USE 
(September 1998)

The Thesaurus Musicarum Latinarum (TML) is an evolving database 
that will eventually contain the entire corpus of Latin music 
theory written during the Middle Ages and the Renaissance. It 
complements but does not duplicate the Thesaurus Linguae Graecae 
(TLG), Thesaurus Linguae Latinae (TLL), Lexicon musicum Latinum 
medii aevi (LmL), and similar projects such as the Center for 
Computer Analysis of Texts (CCAT). The TML, a project of a 
consortium of universities, is managed by a Project Committee, an 
Editorial Advisory Committee, and a Project Director. The Project 
Office is centered at Indiana University--Bloomington. Work on 
the TML has been partially supported by generous grants from The 
National Endowment for the Humanities, an independent federal 
agency. 

Graphics Files: 

The graphics files, by their nature, are somewhat more complex. 
The GIF format has been selected in preference to any other 
format for several reasons. First, GIF files are quite small, and 
thus they can be downloaded very quickly. Second, the format can 
be read on any of the major hardware configurations with simple 
conversion programs available as free- or shareware. Third, the 
graphics files can be displayed directly online by WWW clients. 

---
06. Bodleian Library, Oxford
Towards an Image Catalogue . . . 
http://www.rsl.ox.ac.uk/imacat.html

Below are small, "thumb-nail" versions of four digitized images 
taken from the Bodleian Library's slide collection of 
manuscripts. By clicking on the appropriate images, the larger, 
higher resolution versions can be brought to the client's 
computer. Three methods of viewing each image are provided in 
order to examine their relative merits. By using an "external 
viewer" the user can manipulate the image with the tools provided 
by the viewer used by the client software. (Although the GIF and 
JPEG files are approximately the same size, the JPEG files are 
potentially of greater quality, being more highly compressed and 
capable of handling 24-bit colour.) 

If the image is viewed as an in-line image in an HTML file, it 
can be presented more in the manner of traditional paper 
publications with accompanying annotation, but also with 
hypertext links to other documents, etc. However, modern browsers 
will usually view all forms in-line, rather than spawning an 
external viewer. In this case, if they wish to take advantage of 
the tools provided with an external viewer, they should download 
the image first. 

The four images are taken from a collection of approximately 
30,000 35mm slides of iconography from manuscripts held in the 
Bodleian Library, Oxford, United Kingdom. The GIF images were 
converted from JPEG images that had been processed, using Adobe 
Photoshop, from Photo-CD images produced from the original 35mm 
slides: they have been compressed approximately 10-fold from 
their original file sizes. 

---
07. Digital Scriptorium, University of California at Berkeley
http://sunsite.berkeley.edu/Imaging/

Articles & Papers

Digital Imaging for Photographic Collections: Foundations for
  Technical Standards
An article by Franziska Frey, Research Scientist, Image 
Permanence Institute in RLG DigiNews. 

Reproduction Quality Issues in a Digital Library System 
"Observations on the Reproduction of Various Library and Archival 
Material Formats for Access and Preservation" from the Library of 
Congress. 

Example Decisions on Digital Image Formats 
Practical decisions on image formats for preservation and network 
access by the UC Berkeley Library. 

Technical Recommendations for Digital Imaging Projects 
An excellent "best practices" document from Columbia University.

Toward On-line, Worldwide Access To Vatican Library Materials 
An article from the IBM Journal of Research and Development.

---
07.1 Proposed Standards
http://sunsite.berkeley.edu/Imaging/Databases/#standards
This page was compiled by Howard Besser and refined by Rachel 
Onuf, April 1996. Last edited 11/18/97 

Index to this set of links

     General Overviews of Digital Imaging
     Information about Metadata and Standards
     Ethical & Legal Issues
     Image Capture and Compression
     Image Quality & Conservation
     Technical Protection for Images
     Retrieval issues and search engines for WWW Databases
     Content-based Retrieval
     Costs of Digital Libraries 

     Image Databases on the Net
     Cultural Repositories' Collections
     Unique or Special Image Databases
     Three Dimensional Images
     Sources for Digital Images
     Large-Scale Projects and Initiatives
     Smaller-Scale Projects and Initiatives
     Sample implementations with Image Browsers
     Digital Library Initiatives 

     Additional Resources
     Multimedia Resources
     Research Papers
     Jobs
     Misc

---
07.2 Image Standards Needed
http://www-personal.si.umich.edu/~howardb/ImageDB/standards.html

Prepared for Napa CIMI Meeting
by Howard Besser, Consultant, Getty Art History Information Program
howard@info.berkeley.edu

Major Questions: 

1.Which information must be placed in the image header, and which 
can be placed in an accompanying text record? 

2.For each piece of information we must define: a controlled 
vocabulary (or lack of control) and an identified field to place 
it in 

3.For which of these can we use existing standards? Adapt 
existing standards to our needs? Work with other bodies to make 
sure the standards they adopt will incorporate our needs? Set the 
standards ourselves? 

Information needed to view the image 

   1.-type (bit-mapped, vector, video) 
   2.-format (TIFF, GIF, JFIF, PICT, PCD, Photoshop, EPS, CGM, TGA, ...) 
   3.-compression (JPEG, LZW, Quicktime, ...) 
   4.-dimensions and dynamic range 
   5.-CLUT 
   6.-Color metric (CMYK, RGB, ...) 

Information about the quality and veracity of the image 

   1.-source image digitized 
        1.-the source of that image (recursively) 
        2.-source type 
        3.-source ID 
   2.-institution responsible for creation of the digital image 
   3.-Information about the scanning process 
   4.-light source (full spectrum, infrared, ...) 
        1.-resolution 
        2.-dynamic range 
        3.-type of scanner (for color rebalance) 
        4.-date of scan 
        5.-scanning personnel (in house information) 
        6.-a journal/audit trail of what is done to each image 
          and when it was done (crop, color, adjust, ...) 
   5.-Digital signatures, authentication, ... 

Description of depiction/surrogate 

   1.-VRA terminology on perspective, position, orientation, aspect, ... 
   2.-linking between various views of the same original 

Description of original object 

   1.-AITF categories 
   2.-Systematics 
   3.-AACR2 
   4.-etc 

Rights and Reproduction Information 

   1.-copyright on original, digital copyright, surrogate copyright 
   2.-name of rightsholder 
   3.-use restrictions (viewing, printing, reproducing, ...) 

Location Information 

   1.-URNs, URLs, URCs 
   2.-different versions (browse, hi-res, medium res) derived 
     from the same scan 

The CIMI meeting has organized these in the following way (with 
the header information being a subset of the technical data 
fields): 

Image File with Header

   1.Information needed to view the image 
   2.Rights and Reproduction Information 

Image Technical Data Fields

   1.Information needed to view the image 
   2.Information about the quality and veracity of the image 

Content

   1.Description of depiction/surrogate, surrogate history 
   2.Description of original object 
   3.Rights and Reproduction Information 

Location

   1.Location Information

---
08. The Art Museum Image Consortium (AMICO)
http://www.amico.net/docs/dataspec.final3.shtml

The Art Museum Image Consortium (AMICO) is a not for profit 
association of institutions with collections of art, that have 
come together to enable educational use of the digital 
documentation of their collections. Together, AMICO Members are 
building a joint digital library documenting their collections; 
this Library will be available to University, Public Library and 
Kindergarten through grade 12 educational communities. 

AMICO MEMBERS: FALL 1998

 1. Albright-Knox Art Gallery, Buffalo, NY
 2. Art Gallery of Ontario, Toronto, Ontario
 3. Art Institute of Chicago, Chicago, IL
 4. Asia Society Gallery, New York, NY
 5. Center for Creative Photography, Tucson, AZ
 6. Cleveland Museum of Art, Cleveland, OH
 7. Davis Museum and Cultural Center, Wellesley, MA
 8. Fine Arts Museum of San Francisco, San Francisco, CA
 9. The Frick Collection (including the Frick Art Reference Library), NY
 10. George Eastman House, Rochester, NY
 11. J. Paul Getty Museum, Los Angeles, CA
 12. The Library of Congress, Washington, DC
 13. Los Angeles County Museum of Art, Los Angeles, CA
 14. Metropolitan Museum of Art, New York, NY
 15. Minneapolis Institute of Arts, Minneapolis, MN
 16. Museum of Contemporary Art, San Diego, CA
 17. Montreal Museum of Fine Arts, Montr=E9al, Quebec
 18. Mus=E9e d'art contemporain de Montr=E9al, Montr=E9al, Quebec
 19. Museum of Fine Arts, Boston, MA
 20. National Gallery of Canada, Ottawa, Ontario
 21. National Museum of American Art, Washington, DC
 22. Philadelphia Museum of Art, Philadelphia, PA
 23. San Francisco Museum of Modern Art, San Francisco, CA
 24. San Jose Museum of Art, San Jose, CA
 25. Walker Art Center, Minneapolis MN
 26. Whitney Museum of American Art

1. "MAIN IMAGE" CONTRIBUTED TO AMICO

Each work of art contributed to the AMICO Library must be 
documented by at least one image, showing a full view of the 
work. 

1.1 Resolution

Images contributed to AMICO should have a minimum resolution of 
1024 x 768 pixels. Members are encouraged to contribute larger 
files, to allow for user manipulation. 

[Existing images at resolutions below 1024 x 768 (such as those 
at 800 x 600 created by the National Gallery of Canada for its 
CD-ROM project) will be accepted as part of the university 
testbed library, with the understanding that they may have to be 
replaced in subsequent years. Those museums who intend to submit 
at a lower resolution, are requested to post notification to the 
AMICO Technical Operations Committee Hypernews Discussion. It is 
not recommended that images created for AMICO be at resolutions 
less 1024 x 768.] 

The University Testbed project will study what resolution is 
required for particular functions (e.g. project, lab study on a 
monitor) as an explicit part of its research agenda. These 
findings will be incorporated into the next round of submissions 
of image data to AMICO. 

1.2 Bit Depth:

All images will be 24 bit color.

1.3 File Format/Compression:

Images should be submitted to the AMICO Library as uncompressed 
files in the TIFF format. This will enable future compression by 
a distributor without loss of quality. Certain research uses also 
require uncompressed images. 

AMICO members will also be given the opportunity to produce their 
own compressed files to the specifications of any particular 
distributor. These files would be provided in addition to the 
uncompressed TIFF and on a schedule defined with the distributor. 

Distributors will be asked to declare their image 
sampling/compression processes, for AMICO review and approval. 
AMICO members will also be given an opportunity to review the 
results of distributor's compression routines. 

1.4 File Names 

All associated media files, text, image, multimedia, etc., will 
follow the same naming and linking conventions. 

Filenames will be entered in the appropriate linking field in the 
AMICO main catalog record: Related-Image-Identifier/link, Related 
-Document-Identifier/Link or Related-Multimedia-Identifier/link 

As there are many differing schemes in use in AMICO member 
institutions, file names will not be assumed to have any meaning. 
The characteristics of images will be recorded in their 
accompanying metadata records. ... 

2. METADATA for RELATED IMAGE AND MEDIA FILES:

Each image or other media file will be accompanied by a separate 
structured text metadata record, containing the minimum fields, 
as specified. 

Sample metadata records are posted on the AMICO Web site, along 
with sample image and media files. 

Delimiters and character set specifications are identical for 
metadata records and for the AMICO main catalog record. 

3. RELATED MULTI MEDIA FILES

Associated media files will be contributed to the AMICO Library 
in their native format. i.e. in QuickTime, WAV, RealAudio, etc. 

Files must be accompanied by a metadata record, and referenced by 
an entry in the Related-Multimedia group field of an AMICO 
Catalogue Record. 

Validation routines will test to ensure that all files cited are 
present and that all files contributed are referenced in a 
record. 

4. RELATED DOCUMENTS 

Related textual documents can be contributed in any common format: 

  page images can be in TIFF, GIF or JFIF file format
  text documents can be in ASCII, or Rich Text Format (RTF)
  marked up texts can be in Hypertext Mark-up Language (HTML) or
    Standard Generalized Markup Language(SGML)

Each related document file must be accompanied by a metadata 
record, and referenced by an entry in the Related-Documents group 
field of an AMICO Catalog record. 

Validation routines will test to ensure that all files cited are 
present and that all field contributed are referenced in a 
record. 

---
09. Relationship to the Text Encoding Initiative
http://lcweb.loc.gov/catdir/semdigdocs/hockey.html

5. The TEI and Digital Libraries

The TEI's application of SGML satisfies many requirements of the 
digital library. Its scope already covers the major text types 
and, because of the modular DTDs, it is easily extended to new 
text types. It can handle multiple views and interpretations of a 
text and, through the header, it provides mechanisms for 
documenting the text. Furthermore, the use of SGML is not 
restricted to text. It can be used to describe images and other 
non-textual material and thus provides the link between a digital 
image of a text and its transcription. The TEI has extended the 
cross-referencing systems within SGML to enable them to point to 
complete texts or sections of text stored elsewhere as images or 
transcriptions. 

---
09.1 TEI and XML in Digital Libraries
http://www.hti.umich.edu/misc/ssp/workshops/teidlf/teigrp3.html 

TEI and XML in Digital Libraries, June 30-July 1, 1998,
                          Washington DC.
     Working Group 3: Structural and Administrative
        Metadata in Page-Image Conversion Projects
         Discussion Summary and Recommendations 

Recommendations:

1.Decide on common elements for structural and administrative 
metadata. Determine whether a common syntax/vocabulary for 
elements is necessary, and if so, define. Examine possibilities 
for maintenance of the list. Must be completed before making 
recommendations for transfer mechanisms. 

2.Consult other stakeholders (e.g., preservation community, 
publishing community) when determining the list of common 
elements. The list should be communicated to the TEI leadership 
when complete. 

3.Flesh out the implications of choosing SGML as a common syntax. 
(Consider TEI, EAD, RDF, etc.) 

4.For those who want to use SGML, decide whether TEI should be 
the common DTD or whether we should allow a range of DTDs. 

5.Look into means for facilitating development of and access to 
tools we need for collecting and sharing/exchanging metadata. 
This may involve exploiting the commercial market, but we cannot 
rely on commercial interests to serve our needs. 

6.Raise level of consciousness among decision-makers in the 
library community about the realities of technical requirements, 
costs, etc. 

---
10. SURVEY ON PHYSICAL PREPARATION OF MATERIALS TO BE DIGITIZED
http://www.rlg.org/preserv/joint/index.html

  *** All responses welcome!  Please submit by 14 September ***

The Research Libraries Group (RLG) and the National Preservation
Office (NPO UK/Ireland) are jointly sponsoring a conference 28-30
September which has the overall theme, Guidelines for Digital
Imaging.

In order to gather information about the processes employed in the
preparation of materials for digital imaging, the Working Group on
Preparation has devised a public survey tool.  This survey is
web-based and is available through the conference site:
http://www.rlg.org/preserv/joint/preparation_survey.html or
http://www.thames.rlg.org/preserv/joint/preparation_survey.html
(from Europe)

The following brief description is taken from the introduction to
the survey:

  "The Working Group on Preparation is trying to assess current
  practice relating to preservation aspects, prior to, and
  during, digital image capture. It is hoped, eventually, to produce
  best practice guidelines which will reflect preservation
  needs/concerns during digital image processing."

he following topics will be covered:

 - Guidelines for the selection of collections;
 - Guidelines for the preparation of materials;
 - Guidelines for digital image capture;
 - Issues and approaches to preservation metadata;
 - Progress toward evolving best practices in digital archiving.

For each of the sections addressing "guidelines," working groups
have been formed by the speakers in order to gather information
in regard to the current state of each topic from an international
perspective.  It is through this information gathering and sharing
process that we may begin to identify areas in which consensus might
exist as well as areas where further research and development may be
needed.

For more information on the conference, visit the web site at:
http://www.thames.rlg.org/preserv/joint/index.html (from Europe)
http://www.rlg.org/preserv/joint/index.html (from North America).

---
10.1 Digital Master Quality
http://www.rlg.org/preserv/joint/imaging.html


Objectives: to produce good scans; and to ensure persistence

Questions

Are good scans and good images necessarily the same thing? 

What does "preservation quality" mean? Does the concept of 
"sustainable loss" apply to preservation imaging as it does to 
traditional photographic methods? More specifically, are 
comparisons to photographs, photocopies, or microfilm apt? 

What metric(s) do we use to judge the quality of digital masters? 

If subjective (e.g., going print-to-print), when it is acceptable 
to use uncalibrated devices? 

If objective, which targets and software now exist to make 
practice viable? 

Should we adopt the Quality Index as a method to define and 
describe image quality? 

When should targets be used? 

What are the optimal specifications (for any class of material or 
digital image) for pictorial reproduction? (Attributes include 
color, tone, and detail reproduction; dimensions, cropping, 
skew.) 

Other than pictorial reproduction, what other attributes of the 
digital master should be addressed in these guidelines? 
(Attributes include file format, compression, color encoding 
method, tone distribution, file header information.) 

Under what circumstances is less than best practice acceptable? 

In hybrid approaches where film is scanned ¾ including Photo CD 
projects ¾ is it acceptable to issue scanning guidelines without 
addressing/prescribing the preferred techniques for photography? 

Resources

---
10.2 Metadata issues
http://www.rlg.org/preserv/joint/supdocs.html

RLG working group deemed the following 16 metadata elements 
crucial to the continued viability of a digital image master: 

   1.Date 
   2.Transcriber 
   3.Producer 
   4.Capture Device 
   5.Capture Details 
   6.Change History 
   7.Validation Key 
   8.Encryption 
   9.Watermark 
  10.Resolution 
  11.Compression 
  12.Source 
  13.Color 
  14.Color Management 
  15.Color Bar/Gray Scale Bar 
  16.Control Targets

//end//