403 
raster-to-vector processing. The 'IBIS' technique experiences con 
siderably more histogram and spatial change, but its product contains no 
diagonal connections. Use of the Modified Davis ard Peet technique 
followed by application of the 'IBIS' technique produces a product with 
less histogram and spatial pixel change than the 'IBIS' technique alone. 
Obviously some histogram and pixel conversion is necessary if simplifi 
cation is to occur and a ten acre minimum polygon size is to be ob 
tained, but acceptability of the change can only be evaluated on a case- 
by-case basis. Use of the 'IBIS' approach produces the best 'visual' 
raster or vector product. 
ACKNOWLEDGEMENTS 
Several people have worked on various phases of this research. Dr. Alan 
H. Strahler and Janet Franklin were involved in nearly all facets. 
Boris Gokhman coded the raster-to-vector algorithm into VICAR with some 
modification and improvements. U.S. Forest Service input was obtained 
through discussions with Jack Levitan and Harry Bowlin of the Region 
Five Office in San Francisco. The final Manuscript was typed by 
Gail Linehan at JPL. 
REFERENCES 
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2. Castleman, K.R., 1979. Digital Image Processing. Prentice-Hall, 
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3. Davis, W.A., and F.G. Peet, 1976. The Identification and Reclas 
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4. Goldberg, M., and D.G. Goodenough, 1978. "Analysis of a Spatial 
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7. Russell, R.M., D.A. Sharpnack, and E.L. Amidon, 1975. WRIS: A 
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8. Strahler, A.H., J. Franklin, C.E. Woodcock, and T. Logan, 1981. 
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