Shift and scale invariant preprocessor.

A preprocessor is designed to extract a set of features that enhance natural clustering by removing extraneous information. The design rerroves time shift and scale dependence by taking advantage of invariant properties of a Fourier transform followed by a Mellin transform. The preprocessor is realized using an FFT and a Mellin transform with a conventional error correction term. The error term proves to be indeterminate, but the error's bound is identified as the envelope for Mellin correction terms. Properties of the Mellin transform are employed to modify the signal so that the error correcting is no longer required. The resulting algorithms are tested with variously scaled inputs for which closed form solutions are known. With a verified modification in place, the preprocessor produces features that are invariant to shifting and scaling, while retaining enough information to classify canonic shapes, A method of improving performance is introduced.

Department dc:contributor.department

Electrical Engineering

Grantor dc:publisher

Monterey, California. Naval Postgraduate School

Year dc:date.issued

1981

Author dc:creator

• Huston, Norman E., Jr.

Advisors dc:contributor.advisor

• Wilson, L.A.
• Hamming, Richard W.

Statement dc:rights

• This publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.

Language dc:language.iso

en_US

Handle dc:identifier.uri

https://hdl.handle.net/10945/20667

OAI identifier oai:identifier

oai:calhoun.nps.edu:10945/20667