53 
ischer Boden- 
Digital - 
sdaten vom 
on Forschern 
or fur 
worden. Als 
sowie Farb- 
gsund Boden- 
len Gebrauch 
en. Einige 
auf: 1) 
nung von 
statistische 
ritik der ent- 
des Systems 
were found to comprise numerous spectral signatures, as supporting ground data 
quickly confirmed. Spectral character was but a surrogate, if correctly iden 
tified, for a composite of characteristics such as housing age and quality. 
The map scale of 1:24,000, achieved in line-printer output, was also far larger 
and with accordingly more detail -- than the 1:1,000,000 (and any further low 
resolution enlargement) scale of the visual ERTS images. In a subsequent ex 
periment, Ellefsen, Swain and Wray (1973) encountered similar situations in a 
California urban area. Differences in results were but a product of the varying 
environments. In yet another locality, Brian Erb and others (1973) probed the 
prospect of urban land-use mapping in the Houston, Texas area. Dornbach and 
McKain (1973) followed with a comparison of visual ERTS images and digital 
tapes. Other centers in the' United States attempting the processing of scanner 
data by computer are: Environmental Research Institute of Michigan (ERIM); 
Pennsylvania State University; the University of California, Berkeley; the 
Center for Advanced Computation at the University of Illinois (Urbana-Cham- 
paign); the University of Kansas, Lawrence; the Georgia Institute of Technology; 
and the Mississippi Test Facility of NASA. Some commercial research labor 
atories have also been developing techniques. Earth Information Services 
(1974) of McDonnel-Douglas, for example, conducted a test of machine processing 
of ERTS digital data for the U.S. Army Corps of Engineers in mapping urban 
land use in Oklahoma. 
-1 and follow- 
been made to 
system. While 
aqes recon- 
in false color, 
used. These 
recoqnition 
-drawn" maps 
ion, land- 
th rural and 
ents. 
While not all of these laboratories addressed themselves specifically 
to urban land-use mapping, the results of those who did exposed a number of 
common problems. It has been the express purpose of our work to develop 
methodology which will consistently be able to solve these universal prob 
lems. Specifically, these are: (1) making a sharp distinction between rural 
and urban land uses; (2) achievement of the maximum possible number of cat 
egories of urban land uses at; (3) levels of accuracy high enough to make the 
product credible and useful to urban planners and; (4) to have the computer 
aggregate the data by jurisdictional and other statistical units. Earlier 
advances along these lines are presented in Ellefsen, Gaydos, and Wray (1974) 
and Ellefsen (1974). 
scover how 
n be employed 
els of corn- 
satellite's 
e highest 
ical number 
ds possible 
Solutions to all of the problems have been sought throughout work on 
each of the test sites -- Arizona, Missouri, and Indiana -- and gains have 
been made in each. Since the experience has been cumulative, the highest 
level has been reached in the recently completed Indianapolis work. For 
purposes of clarity, considering the complexity of the analysis procedure, 
a recitation of the methodological steps precedes a discussion of how 
features of the method were directed toward solution of each of the stated 
problems. 
the last 
h computer 
ner infor- 
hers at the 
versity 
, Wiscon- 
concep- 
as alike 
METHOD 
As a first step, ERTS computer compatible tapes from contrasting seasons 
covering the area of interest are selected and reformatted for interaction 
with the LARSYS package of pattern recognition programs. A quarter sampling 
is taken of the total data (every other line and column). This proves to be