AUTOMATIC EXTRACTION OF INFORMATION FROM
MULTISPECTRAL SCANNER DATA *
Jon D. Erickson
Environmental Research Institute of Michigant
P.O. Box 613
Ann Arbor, Michigan
Abstract
The present status of automatic multispectral scanner data processing
and interpretation is evaluated with problem areas and suggested approaches
discussed. The rationale for automatic information extraction is given.
The basis of spectral discrimination is examined indicating sources
of systematic variability which tend to obscure the spectral attributes
of the classes of interest.
Automatic processing functions, techniques and methods, and equipment
are discussed with emphasis on preprocessing for feature enhancement
and invariance, which accounts for sources of systematic variability and
reveals the underlying class signature otherwise obscured. Techniques for
carrying out the major functions of preprocessing, signature extraction,
discrimination, display, and post-processing are examined in detail.
Procedures are reviewed for adaptive discrimination and for estimating
the proportions of classes within a single ground resolution element. A
special purpose multispectral parallel-channel processor system is
presented.
Applications and results are discussed briefly in terms of agricul-
tural and geological surveys to indicate the substantial success achieved
to date.
It is concluded that despite the potential demonstrated in the many
successful feasibility tests in various application disciplines that
operational uses of information derived from multispectral sensing of
earth resources and land use will await development of cost effective
processing systems.
*Supported in part by NASA Contract NAS9-9784.
tFormerly the Willow Run Laboratories of the Institute of Science and
Technology of The University of Michigan.
1