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Converting Interactive Laserdisc to Interactive Digital Video: A Demonstration Using the University of Washington Human Brain Animations Chiang S. Jao, Ph.D., Daniel B. Hier, M.D. and Steven U. Brint, M.D. Department of Neurology, University of Illinois, Chicago, IL 60612-7330 Microsoft Video-for-Windows (under the environment) to capture sections of the laserdisc animations as audio-video-interleave (AVI) files. Cinepak CODEC compression technology offers more favorable data rates on AVI files. We collected more than 100 AVI files from the laserdisc. We then interleaved narration in the form of recorded audio waveforms (WAV) with the AVI files since no narration was on the original laserdisc.
ABSTRACT
Interactive laserdisc is a powerful medium for the communication of subjects that involve 3D animation, rotations, or translations. This technology has been used to produce multimedia programs with fullmotion animated video and CD-quality stereo soundtracks. The primary advantage of laserdisc technology over conventional videotape is the ability to randomly access and display video sequences or still video frames quickly. Furthermore, unlike videotapes, laserdiscs do not need to be rewound. Although computer-driven interactive laserdisc is a powerful multimedia teaching tool, there are disadvantages to this technique. First, a device driver must be installed on the computer to drive the laserdisc. Installation of these device drivers may be difficult and complex. Second, in the absence of a device driver or a computer interface on the laserdisc player, random access to the desired video sequence may be difficult or cumbersome. Third, video output from the laserdisc player cannot be displayed on the computer monitor unless a specialized video overlay card is installed in the host computer. These video overlay cards add expense and require additional specialized drivers. Fourth, it may be prohibitively expensive to create more than one or two training stations that consist of a computer, a computer monitor, a video monitor, and a laserdisc player. Fifth, some laserdisc programs lack audio tracks. Mixing in narration to laserdiscs lacking audio may be cumbersome. Finally, laserdisc-based educational programs require users to handle delicate videodiscs and run the risk of inexperienced users damaging the discs.
Our driver program is implemented in KnowledgePro for Windows® (KPWIN), an expert system shell with hypermedia capabilities. KPWIN allows the system to communicate with external multimedia devices via MCI (Media Control Interface) commands. KPWIN calls external DLL (Dynamic Link Library) functions in Windows to issue these command strings. KPWIN implements a backward-chaining heuristic mechanism with IF-THEN statements. The hypermedia capability of the KPWIN allows the use of text, graphics, hypertext, and hypergraphics to link a functional execution. KPWIN supports a contextual indexing method to speed up data retrieval from external database files. We designed a topic-oriented host window with button-driven control to play audiovisual files. Each button is associated with a list of subtopics related to the selected major topic. Every subtopic invokes the play of an audiovisual file on the host computer. A control panel allows the user to fast forward ahead or to freeze any video frame for extended viewing. The play of interleaved stereo soundtrack offers a narration for the displayed brain animation. By converting laserdisc to digital video, the program offers the advantages of the laserdisc technology but avoids the need ofthe laserdisc player during the operation of the program. The expert system technology and data indexing methods provide a powerful interface to the brain animations. We have developed an interactive multimedia-based animation program to teach medical students about the key brain components. The Brain Animation project gives the user a convenient tool to access computer-generated brain animations without requiring the use of a laserdisc player or VCR.
To address some of these disadvantages, we decided to build an educational brain anatomy program by converting laserdisc to digital video. We purchased a series of computer-generated brain animations from the University of Washington on laserdisc. These are an excellent set of brain animations that reveal anatomic relationships between multiple brain structures including the ventricles, the basal ganglia, hippocampus, and thalamus. Laserdisc is an ideal medium for conversion of these animations to digital video. We used the Intel Indeo Video technology 0195-4210/94/$5.00 ( 1994 AMIA, Inc.
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