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4. APPLICATION TO ROUTE SELECTION 
41 Production of stereoscopic images overlaid with 
other useful information 
This digital photogrammetric system with stereoscopic 
image processing software can be used effectively in 
many fields, such as earth resource exploration, route 
selection, dam construction, regional development, etc. 
Experimental applications of this system have already 
been made in some fields, and two of them will be 
explained here. 
One of the applications is in the field of route selection, 
such as for roads, pipelines, microwave communication 
routes and high— voltage electric wires. Here, as one 
application example, route selection for microwave 
communication will be shown. In this case, some 
information which is useful for the work is at first written 
on an orthoimage using the calculation program 
developed in this system, and then transformed to 
stereoscopic images. By looking at these stereoscopic 
images with liquid crystal shutter glasses, an operator can 
get precise topographic information together with images 
and other useful information. 
Photo 6 shows the stereoscopic images displayed 
alternately. In this photo, two images are taken as if 
overlaid. Two kinds of information are overlaid on these 
images, the faults, shown here by bright broken lines, 
and the active faults, shown by dark broken lines. An 
operator can see a stereoscopic model by looking at the 
alternative display through liquid crystal shutter glasses. 
The information gotten from the model is as follow: 
(1) Locations of lakes, roads, villages, etc., which are 
taken in the images. 
(2) Locations of overlaid faults and active faults. 
(3) Topographic information obtained by observing the 
stereoscopic model. 
  
Photo 6 Stereoscopic images overlaid with other 
useful information 
269 
4.2 Route selection using the 3D display module 
Photo 7 shows one example of analysis using these 
overlaid stereoscopic images. The steps for selecting a 
route for microwave communication are as follow: 
(1) An operator, by observing the stereoscopic model, 
examines the conditions of the areas where parabolic 
antennas for microwave communication are planned to be 
constructed. 
(2) The operator indicates two points on the model which 
seem to be good locations for antenna construction. In 
the photo, these points are shown by two pairs of cross 
points. 
(3) The computer automatically ties the two pairs of 
points by a pair of lines on the stereoscopic images, then 
outputs a cross— section of the earth’s surface under the 
line, which can be drawn using the DEM extracted 
beforehand; it then calculates the quality of the 
microwave communication between the two points using 
the cross— section produced. The cross— section is shown 
in the photo by a wavy line. The scale of the wavy line is 
shown by 5x5 crossed lines. 
(4) The operator at first checks the area surrounding the 
route for microwave communication by observing the line 
and the image near the line on the stereoscopic model; 
he then inspects the quality of the microwave 
communication by using both the surface cross— section 
and the calculated value of microwave communication 
quality. 
By using this method, much field work can be replaced 
by computer work, and time and money can be reduced 
drastically. 
  
Photo 7 Route selection for microwave communication 
5. APPLICATION TO EARTH RESOURCE 
EXPLORATION 
5.1 Relationship between B/H ratio and extractive 
lineaments 
International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B2. Vienna 1996