STEREO VIEWING 
REAL TIME MANIPULATION OF DIGITAL IMAGE DATA 
ABILITY TO MODEL SENSOR AND OBJECT SPACE GEOMETRY 
The additional features which are expected include image processing, use of automated techniques, 
integration of vector data and use of basic photogrammetric functions. The ability of a DPW to be 
used as an analytical stereo plotter with continuous scroll puts heavy demands on the hardware, 
there is no doubt though that the operator needs an instrument which is convenient to use and at 
which he does not have to wait for data to be displayed or for other operations to be carried out. 
The photogrammetric operations are listed in Table 1 with their requirements on instrument 
performance. 
Table 1. Photogrametric operations and their requirements in terms of instrument performance. 
OPERATION VIEWING REQUIREMENT SPEED REQUIREMENT 
INNER ORIENTATION 
Measure fiducials 
Mono viewing of small area 
Immediate* display of 
predefined fiducial area. 
Compute transformation 
Nil 
Immediate response 
ORIENTATION 
Measure image co-ordinates 
of homologous points, 
(orientation and control) 
Stereo viewing over limited area 
Immediate display of 
predefined point positions 
Compute exterior orientation 
Nil 
Immediate response 
FEATURE EXTRACTION 
Image enhancement 
Interactive on whole scene or 
on windows 
Real time processing 
Measure points 
Continous stereo 
Smooth scroll 
Record lines 
Continous stereo 
Smooth scroll 
Record lines with x parallax 
removed 
Continous stereo 
Smooth scroll and real 
time matching 
Identify features 
manual 
automatic 
Continous stereo 
Nil 
Nil 
Fast response 
DERIVE DEMs 
Measure heights 
Nil 
Off line process 
Interpolation etc 
Nil 
Off line process 
Validation 
Stereo viewing with DEM 
superimposed 
Perspectuve view 
Real time scroll of image 
and vector overlay 
UPDATE DIGITAL DATA 
Stereo viewing with vector 
overlay. 
Real time scroll of image 
and vector overlay. 
Data base access and edit. 
Immediate means no waiting 
240