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Two-dimensional convolute integers for optical image data processing and surface fittingAn approach toward low-pass, high-pass and band-pass filtering is presented. Convolution coefficients possessing the filtering speed associated with a moving smoothing average without suffering a loss of resolution are discussed. Resolution was retained because the coefficients represented the equivalance of applying high order two-dimensional regression calculations to an image without considering the time-consuming summations associated with the usual normal equations. The smoothing (low-pass) and roughing (high-pass) aspects of the filters are a result of being derived from regression theory. The coefficients are universal integer valves completely described by filter size and surface order, and possess a number of symmetry properties. Double convolution lead to a single set of coefficients with an expanded mask which can yield band-pass filtering and the surface normal. For low order surfaces (0,1), the two-dimensional convolute integers were equivalent to a moving smoothing average.
Document ID
19750022769
Acquisition Source
Legacy CDMS
Document Type
Technical Memorandum (TM)
Authors
Edwards, T. R.
(NASA Marshall Space Flight Center Huntsville, AL, United States)
Knight, R. D.
(Calif. Univ. Berkeley, United States)
Date Acquired
September 3, 2013
Publication Date
May 28, 1975
Subject Category
Numerical Analysis
Report/Patent Number
NASA-TM-X-64949
Report Number: NASA-TM-X-64949
Accession Number
75N30842
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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