4.2.2.3 Ease of Creation and Interaction for Multimedia
When project goals called for the inclusion of multimedia in the knowledge base,
unique "usability" issues emerged.
After an accessible database of text was constructed during the ESCAPE project,
the highest priority became making it more engaging by adding digitized sound,
color graphics, and short video clips about career-planning and engineering design.
After expensive equipment and software were acquired, the feasibility of storing
large amounts of high quality media hampered efforts. ESCAPE, which was distributed
over a network, included only a few short sound bites and color pictures.
While storage was one limitation, adding multimedia with the tools available
was also a highly inefficient and prohibitive process. The media required
translation and editing once they were digitized. Video capture was the most
inefficient to work with, and required editing before it could be effectively
incorporated in the HyperCard based courseware.
For Intermedia, which was designed to allow easy learner construction of multimedia,
the "usability" of hardware peripherals needed to be addressed before learner
construction could become practical. One of the more subtle issues was addressed
by the Norm Meyrowitz, who was the leader of the technical team that developed
Intermedia.
We have to start working with the developers of these technologies
to get them to recognize that these devices need to be intrinsic and integral
to our system, so that they work seamlessly. You can't create systems that
have all of the peripherals working as if they just met the CPU today.
They have to be intimate, so the scanner, the OCR, and the handwriting
recognition work well with the system. It's a matter of having hardware
developers and peripheral developers work closely with the hardware platform
developers and system software developers. So "peripheral" is a misnomer.
Input/output technologies must not be peripheral to the system, but rather
central to an integrated environment.
(Meyrowitz, 1991, p. 310)
While the frustrating lack of "usability" for hardware was a commonly
expressed frustration among developers of multimedia, there was another
less discussed hardware related problem that stood in the way of learner
construction of storage intensive multimedia. Many hail the cheap and
distributable CD-ROM storage as a boon that will help in the struggle
to bring computers to education across the curriculum. This celebration
does not take into account that unchangeable storage is antithetical to
the learner constructed mode of education which the computer is so uniquely
equipped to support. This weakness of the CD-ROM technology was also
addressed by Meyrowitz of Intermedia:
We need a removable storage medium of the 1990's.
We need cheap random access, exchangeable, ubiquitous storage-the
gigabyte floppy. We must not think that we have all the storage problems solved.
CD ROM and CD-I technology is a weak technology for interactive computing.
It's great technology for transmitting information because CD duplication
simply involves stamping out injection-molded plastic, which is much cheaper
and much faster to do than recording magnetic media. But we don't want to be
condemning all data to be read-only and non-malleable. We want individuals to
be able to annotate and manipulate the information. We need to start making sure
that we have a ubiquitous medium that is as dense as CD ROM but is also very
interactive. We need to have removable medium of the 1990's just like the 3 1/2"
disk of the 1980s. But it has to be a 1 gigabyte floppy disk that is cheap
and with which everyone can transmit information, store information,
and link information.
(Meyrowitz, 1991, p. 310)
The need for improved authoring interfaces for advanced distributed
computing environments was the main reason for the Visual Computing Group (VCG)
becaming the Center for Educational Computing Initiatives (CECI), and continuing
to develop the AthenaMuse authoring package.
After developing the multimedia workstation with its basic capacities
for handling text, graphics, video and audio, we realized the system was not easy
to use. Without any high level information processing tools, the only access to
the machine's potential was through UNIX, C, the X-Windows System, and the X Toolkit
programmer's support package. (Davis, 1990, p. 16-2)
The importance of the "usability" of tools for the creation and manipulation of
multimedia formats has been a high priority of the developers of Athena Muse.
They identified one of the major contributing factors to "usability" of a
package to be the data model, as demonstrated in the passage below:
The human interface begins with the data model. If the data
model does not fulfill the purposes of the systems as a whole, any efforts
on the more superficial aspects of the interface will be largely wasted.
(Hodges, Sasnett, & Ackerman, 1989, p. 42)
In the following passage, it is also clear that beyond the data model,
there are a other critical issues that pose challenges to those who wish
to work with multimedia, that have not been a problem with more traditional formats:
Motion video and audio data are fundamentally different from text
documents due to their temporal structure. Establishing cross-references th
at
incorporate such data in a hypermedia system poses a number of challenges.
It is possible to model video as a stream of individual frames, just as text
can be modeled as a stream of individual characters. When video stops,
a fixed image must be considered. Audio is different, however, for when
it stops there is only silence; its meaning inheres in its change over time.
(Hodges, Sasnett, & Ackerman, 1989, p. 38)
The differences in the nature of working with different forms of digital data
were recognized before the creation of the AthenaMuse, and drove the design of
their multimedia control package. In fact, the creation of the "dimensions"
as a critical component of their data model emerged because of the need to meet
the challenge of manipulating and controlling various different multimedia formats
within the same paradigm. In the passage below they summarize why their
multi-dimensional data model was most apt for manipulating audio, video and text:
This turned out to be a "spatial model" that describes the dimensions
of information space, and placement of items or documents within that framework.
Under this approach, a document is constructed around an abstract dimension of
time that can be displayed and manipulated as a time-line on screen.
Each piece of video and each text subtitle can be mapped into this framework
according to onset and offset times.
(Hodges, Sasnett, & Ackerman, 1989, p. 42)
Beyond their selection of a powerful data model to control multimedia,
the AthenaMuse team emphasized other attributes within AthenaMuse to make
it more powerful and usable for authoring in the future. One attribute was
the inclusion of "plastic editors"
(Davis, Sasnett, & Hodges, 1989).
This term refers to the ability to edit the editors themselves so they
can be customized and combined at need or used as part of the on-line documentation.
The second key theme the AthenaMuse team emphasized was the importance of
the ability to manipulate digitized video:
Using the digitized approach to video in the workstation offers
significant advantages over the analog approach used in earlier systems
because of the additional flexibility. Once the image has been digitized
it can be stored and retrieved from any digital storage device.
Single images can be taken from the video stream and displayed elsewhere
on the screen or stored for later use.
(Champine, 1991, p. 153)
Ben Davis, Manager of CECI, believes a relationship exists between their
efforts to make AthenaMuse easier to use, and the learner's educational experience.
Already, with the first materials, we can see a change.
In the past, teachers prepared materials and students reviewed them.
Now, students are asked to create. With a broad array of expressive media,
the ability to create complex visual image combined with text and numbers,
students will be allowed to articulate their own perceptions.
(Davis, Sasnett & Hodges, 1989, p. 35)