Ph.D. Thesis Available

Alex Sherstinsky shers at hing.lcs.mit.edu
Wed Jun 8 21:29:50 EST 1994


M-Lattice: A System For Signal Synthesis And Processing Based On

                            Reaction-Diffusion

				   OR:

  M-Lattice: From Spots and Stripes on Animals to Signal Processing

		              Sc.D. Thesis

			   Alex Sherstinsky

                         MIT EECS & Media Lab

                               Abstract

This research begins with reaction-diffusion, first proposed by Alan
Turing in 1952 to account for morphogenesis, such as the formation of
hydranth tentacles, leopard spots, and zebra stripes.
Reaction-diffusion systems have been researched primarily by
biologists working on theories of natural pattern formation and by
chemists modeling dynamics of oscillating reactions.  The past few
years have seen a new interest in reaction-diffusion spring up within
the computer graphics and image processing communities.  However,
reaction-diffusion systems are generally unbounded, making them
impractical for many applications.  In this thesis we introduce a
bounded and more flexible non-linear system, the ``M-lattice,'' which
preserves the natural pattern-formation properties of
reaction-diffusion.

On the theoretical front, we establish relationships between
reaction-diffusion systems and paradigms in linear systems theory and
certain types of artificial ``neurally-inspired'' systems.  The
M-lattice is closely related to the analog Hopfield network and the
cellular neural network, but has more flexibility in how its variables
interact.  The bounded M-lattice enables computer or analog VLSI
implementations to serve as simulation ``engines'' for a wide variety
of systems of partial and ordinary differential equations.

On the practical front, we have developed new applications of
reaction-diffusion (formulated as the new M-lattice).  These include the
synthesis of visual and sound textures, restoration and enhancement of
fingerprints, non-linear programming, and digital halftoning of images.
Halftones were synthesized in the creatively hand-drawn ``special-effects''
style of the Wall Street Journal portraits as well as in the
``faithful-rendition'' style of error-diffusion.

Thesis Supervisor:  Professor Rosalind W. Picard

To obtain: ftp whitechapel.media.mit.edu anonymous anonymous cd pub/shers
           get thesis.ps.Z

Enjoy!
-- 
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|Alexander Sherstinsky|shers at mit.edu|To become as refined a person as possible.|
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