15 
localized image detail can cause an undesired 
count. The improvement would be greater, except 
that only information in the central part of the 
scan is used for correlation, resulting in a signifi 
cant time loss. The larger area provides the 
operator enough of a picture to be useful, while 
correlation is limited to a smaller area to obtain 
a more meaningful measurement of the altitude 
for the central point. 
Because the effectiveness of the UAMCE oper 
ational cycle remains to be verified, it is not too 
useful to speculate on how much shorter the time 
can become. If the equipment were improved to 
a point where operator attention was not required, 
the scan could be confined to the area used for 
correlation. This might permit a factor of two 
improvement. Faster scanning would require a 
higher bandwidth and, consequently, brighter 
scanners; some gain might be obtained in this 
way, but it would be at the cost of poorer resolu 
tion and perhaps less life from the scanner tubes. 
It is anticipated that significant improvements 
in the UAMCE will result from programming 
modifications that will permit the density of the 
measurements to adapt to the terrain. To obtain 
altitude information in conformance with usual 
map standards, it will be necessary to have at 
least two measurements per contour interval. In 
flat areas the measurement interval can be large, 
allowing such areas to be covered quickly; in 
areas of high relief, the density of measurement 
must be very high (unless it is not important to 
maintain the accuracy). It has been estimated 
that the UAMCE will compile 9- by 18-inch, 
100% lap diapositives in about 3 hours using (at 
nominal scale) 250-micron (0.01-inch) spacing 
along the profile, and 500-micron (0.02-inch) 
spacing between profiles. For very flat areas this 
could be changed to, say, 1000 microns between 
profiles and, with modification of the computer 
programs, an equal spacing along the profile; this 
would permit a 9- by 18-inch, 100% lap pair to be 
compiled in less than half an hour. The program 
should be made to adapt to the terrain to minimize 
the time required for each model, while maintain 
ing the required accuracy. 
The UAMCE will be improved gradually as 
other new computer programs are written. These 
will permit manual measurement of spot heights 
with hard-copy printout, so that the data can be 
added to the map. It will probably be desirable to 
write a program to allow the operator to contour 
manually in selected areas (as in a forest, where 
the operator can use judgment to extend whatever 
stereo coverage of the ground is available); the 
program would print out the altitude chart on the 
basis of the manually made measurements, but 
print out the orthophoto on the basis of machine- 
made measurements, preserving the dominant 
imagery on the orthophoto. Undoubtedly, still 
more programs will be found desirable to opti 
mize the operation and minimize the demands on 
the operator. 
Of course, it would be desirable to print out 
contour lines, rather than the present rotary 
sequence of three gray tones. However, until 
annotated contour lines (not requiring manual 
touchup) can be automatically drawn, the product 
would not be as useful as the present output. The 
three-tone sequence is very easy to follow and 
easily smoothed to obtain the final product. 
The UAMCE should print orthophotos at up to 
40-line/mm resolution without any noticeable 
joint between the individual small areas making 
up the composite output. The high resolution per 
mits outputs at reduced scale, so that high quality 
mosaics from contiguous stereo pairs can be made. 
While orthophotos may be adequate and desirable 
for large scale maps, they are not useful for small 
scale maps. Continued efforts will be required to 
automatically abstract the desired planimetric 
detail from the orthophotos. 
Many groups are working on the problem of 
recognizing important details in photographs. The 
compilation problem demands attention to a new 
class of recognition problems (such as, in an 
area under examination, can the structure of the 
area be discerned from the resulting electrical 
signals?). The stereo signals should make recog 
nition easier (assuming the scale of the photog 
raphy is such as to reveal height variation in the 
features to be identified). It may be useful to be 
able to place upper and lower limits for the alti 
tude variations within an area rather than being 
constrained to use the weighted average altitude 
where the weighting favors the high information 
content signals. 
In the series of equipment developed thus far, 
no attempt has been made to store any significant 
amount of the altitude data, except through the 
altitude chart. It should be realized that the com 
pilation process requires that the measured height 
of each elementary area be available in digital 
form at some time. It would be a trivial task to 
store these data on magnetic tape, making them 
available for later use for many applications. For 
example, the data might be used for cutting relief 
models, for calculations required for cut-and-fill 
operations, or for calculating the expected cover 
age of a radar as a function of possible sites. 
CONCLUSION 
The development of the Automatic Map Com 
pilation Equipment at Bunker-Ramo has been 
sponsored by the U.S. Army Engineer Geodesy, 
Intelligence and Mapping Research and Develop-