Computer Experience
Professional Experience:
2002-Present -- Joint Venture of Vectaport Consulting and Theseus Research Inc.
Development and marketing of an extensive intellectual property portfolio: 3d image filtering techniques; self-timed logic design; and a pipeline-oriented concurrent programming methodology. First product is a Mac OS X application for 2d and 3d image transformation using a patented non-aliasing technology (PixelCoaster).
2000-2002 -- Accom Inc, Menlo Park, California
Principal software engineer on leading stand-alone digital video effects device for live broadcasting (Dveous). Responsible for overall software environment, control panel user interface, multi-format timeline (interlaced, progressive, segmented), keyframe-based effects editing. Successful development and delivery of High-Definition version in Q4 2001. Ongoing support for video switcher protocols. Established working relationships with video switcher engineering teams at both Thomson, Sony, and GVG.1999-2000 -- IET Inc., Arlington, Virginia
Construction of heterogenous client-server systems for visualization and processing of geo-spatial data. Responsible for the organization and evolution of layered vertical application frameworks, both open-source and proprietary, and the time-critical delivery of prototype systems.
1992-1999 -- Vectaport Inc., Redwood City, California
President and lead programmer of Vectaport Inc., which specialized in the development of spatial data applications for Unix and X Windows written in C++. Worked on a variety of direct-manipulation editors/viewers/browsers built on top of John Vlissides' Unidraw: a scientific imaging workstation for NASA Ames, a hierarchical decision-tree editor for uncertainty reasoning, and a geo-spatial event simulation for miltary analysts. Integrated a networked command interpreter into the Unidraw architecture and applied it to artificial intelligence applications in image and terrain understanding.
1989-1992 -- Advanced Decision Systems, Mt. View, California
Developed user interface software for a variety of graphical/image oriented analytical workstations (radiology, research biology, military analysis). Organized a reusable library of InterViews 2.6 user interface objects. Instituted a project management software system built on top of cvs and rcs.
1985-1989 -- Triple Vision, Inc., Minneapolis, Minnesota
Developed software and evolved algorithms for imaging applications: video-based vehicle counting, address block location for zip-code OCR systems. Developed prototype command interpreter for real-time image understanding applications. Founder responsible for overall software technology. Created libraries of reusable imaging software and instituted a project software management system.
1984-1985 -- MIT Lincoln Laboratories, Hanscom AFB, Massachusetts
Worked on system for radar tracking of deep-space satellites. Developed distributed project software management system.
1979-1983 -- Honeywell Systems and Research Center, Minneapolis, Minnesota
Developed software for recognition of tactical targets in infrared and radar imagery. Constructed minicomputer based imaging systems accelerated by specialized image processing peripherals (IIS Model 70). Developed and promoted a reusable library of FORTRAN based image processing software.
Education:
Bachelor of Computer Science, University of Minnesota, Minneapolis, Minnesota, 1981
Publications:
"Command Language for Developing Real-Time Signal and Image Processing Applications", S. Johnston, R.C. Fitch, SPIE Proceedings on Automated Inspection and High Speed Vision Architectures II, vol. 1004, Nov. 1988.
"Progress Toward an Image Understanding Application Development Environment", T.S. Levitt, S. Johnston, S. Barclay, J.W. Dye, DARPA Image Understanding Workshop, Sept. 1990.
Bayesian inference for model-based segmentation of computed radiographs of the hand, Levitt TS, Hedgcock MW Jr, Dye JW, Johnston SE, Shadle VM, Vosky D., Artificial Intelligence in Medicine, Aug. 1993.