SLICE OF LIFE BE MADE DIGITAL?
For the past
decade, the Slice of Life project produced seven editions of a videodisc-based
visual encyclopedia of images related to medicine, nursing, and allied
health education. Descriptions for the 44,000 images were indexed in FileMaker
Pro databases for both the Macintosh and Windows platforms. Use of the
images involved a video monitor and a stand-alone videodisc player with
a hand controller or barcode reader. Many integrated the disc with computer-based
tutorials and test banks that controlled the playback of appropriate frames
from the videodisc.
image conversions (JPEGs) from analog videodisc originals
Many users have asked if the analog pictures from the videodisc can be
converted into digital image files (such as jpegs) for use on CD-ROMs,
DVD-ROMs or the World Wide Web. We have experimented with many methods.
However, the production task proved too daunting. Each of the 44,000 analog
frames from the videodisc would require individual hand-crafted image
enhancement in order for it to look decent in the higher resolution world
of computer digital imagery. We decided to forego this process and instead
encourage the use of other, new collections in which jpegs have been digitized
directly from very high quality source materials, such as original 35mm
transparencies or x-rays.
about a DVD-Videodisc?
This is a very popular question for our office. The answer is unfortunately,
"No." Here is the background information:
- A DVD-Videodisc
is optimized for motion video. The image compression codec used on DVD-Videodiscs
is MPEG2. It is specifically designed to analyze the differences and
similarities of image content in a motion video scene. Based on its
analysis, the MPEG2 encoder dismisses, compresses, and accommodates
specific image data.
- The original
Slice of Life 12-inch analog videodisc took advantage of what was called
the CAV or Frame Accurate Interactive mode possible on analog videodiscs.
That meant up to 54,000 still images could be recorded to a laser videodisc.
Each frame was randomly accessible when controlled by a hand controller,
a laserbarcode reader or through computer drivers.
- It is
possible to encode still images onto a DVD-Videodisc. Many special edition
versions of motion picture films include still images in filmographies,
bios and production notes. But have you noticed that the menu and scene
selection structure of a DVD-Videodisc is not very granular? The menus
interactively transport you to specific "chunks" of DVD material.
However, when a group of still frames are encoded on the DVD, you are
typically required to use the "step forward" button on your
remote control to browse those still images.
- With 54,000
still images on the Slice of Life videodisc, it would be impossible
to create a menu structure that would allow you to randomly and interactively
access any single frame on the DVD-Videodisc. Perhaps a menu could take
you to a section on cardiovascular images, but then you would be forced
to browse through the images manually using your DVD hand controller.With
so many images to choose from, this would be incredibly inefficient.
Additionally, on a standard DVD-Videodisc player, each still image does
NOT have its own frame address like it did on the 12-inch laser videodisc.
Our database indexes of image descriptions could not reference a particular
frame on the DVD for you to view.
there is a special DVD Player made by Pioneer (DVD-V7400,
US$700) that has barcode and individual frame address capability. It
allows you to access individual frames or scenes from a specially encoded
DVD-Videodisc by using barcoded indexes or by punching in a DVD frame
number on a hand controller. The barcodes for the player are not compatible
with the 54,000 barcodes we already created for the 12-inch laser videodisc.
The frames numbers also do not correspond to the indexed frame numbers
we created for the original 12-inch laser videodisc.
- The special
Pioneer DVD-V7400 also has a serial port which should allow it to be
controlled by computers. However, none of the older generation laser
videodisc drivers (Mac or PC) are compatible with this DVD-player. Our
investigations have shown that there is no active support for creating
these DVD drivers, with perhaps the exception of a multimedia authoring
package called HyperStudio (www.hyperstudio.com).
- As an
experiment, we wrote a DVD-Videodisc from the original 12-inch laser
videodisc. We eliminated the MPEG2 capability to analyze the differences
and similarities between frames by forcing each image to be a "keyframe"
or "I" frame. During the digitizing process, 4 images from
the videodisc were dropped and not digitized. We could never figure
out which 4 frames out of the 54,000 were missing. Thus, we could not
correlate the new DVD frame numbers with the old 12-inch laser videodisc
frame numbers. There was no consistency.
- In this
same experiment, we were not satifisfied with the image quality of each
frame encoded on the DVD-Videodisc. The MPEG2 codec simply is not designed
to maximize the quality of a single video frame. The frame may have
been "digital," but the "analog" original found
on the 12-inch laser videodisc looked better.
are several companies creating DVD-Videodisc controller software utilities
that work from within a web page and call up DVD-Videodisc sequences
from a computer's internal, installed DVD player. Although it is too
early to know if individual frame access is possible, this new interactivity
holds great promise for integrating full-frame, full-motion, high quality
video sequences into html pages. At the present time, there is no cross-platform
utility on the market. Here are two links you may wish to investigate
for Windows-based computer solutions:
1000 Neuroscience Images on the Web
of Utah Eccles Health Sciences Library Multimedia Catalog contains images,
illustrations, animations, videos and sounds related to the health sciences.
1000 neuroscience images contributed by Suzanne Stensaas and Eugene O.
Millhouse from the Slice of Life videodisc are part of this catalog of
for "stensaas" or "millhouse" or use other relevant
subject keywords. The multimedia items are designed to be re-purposed
for educational and non-profit use. The Catalog is accessed through the
Ameritech Horizon Integrated Library System, with each multimedia item
fully cataloged by a professional librarian. Medical Subject Headings
(MESH) are used to describe each record, as well as local subject headings
A Digital Brain Atlas on CD-ROM
Stensaas, Dr. Suzanne Stensaas, Derek Cowan and Jeremy Smith at the Eccles
Health Sciences Library, University of Utah, have been working on a wonderful
new project called the Digital Brain Atlas. Much of the interactivity
was programmed using Flash. The imagery and labeling techniques are top
notch. See an online demo of the CD-ROM at http://library.med.utah.edu/eccles/slice/brain.html.