2004 
  
International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B6. Istanbul 2004 
  
EN 
Figure 5. Superimposition vector information over infrared stereoscopic model (StereoCaptor tool) 
The main characteristics of StereoCaptor tool are: 
Stereoscopic cursor displacement functions: 
- click and drag area selection, 
- roaming using the ground positioning 
through correlation functions, 
- roaming using a previous digital elevation 
models available on the area. 
Focus and parallax adjustment associated to the 
mouse wheel or keyboard. 
Zoom functions: windows zoom, zoom in, zoom 
out, model extension zoom, zoom 1:1 
Move to point function: the cursor will be displaced 
to a specific X, Y,Z position that is included in any 
of the project models. 
XYZ cursor position will be displayed in real time. 
Measure tool: Accumulated distance length 
measurement and the area and perimeter polygon 
calculation. 
The options will be available from main menu, tool 
bar or accelerator keys and the user-defined cursor. 
Cursor movement using a mouse or keyboard. 
User configurable display resolutions depending on 
the available graphics card. 
Semi-automatic model selection loading among the 
project models and among the available projects. 
Save user configuration for later executions. 
3D view print capability. 
It is possible to store a determined model in the 
main memory in order to improve the speed for 
slow computers. 
Vector information visualization of the active file 
and other reference files. Capturing and edition of 
vector information and associated attributes. 
If there are no stereoscopic models available, it is 
possible to use an orthoimage for feature extraction 
using the OrtoCaptor tool. If a DEM is available, it 
is possible to obtain 3D information (Z coordinate 
accuracy will be the corresponding of the associated 
DEM). 
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4. ON-LINE ORTHORECTIFICATION 
OrtoMotor (OrthoEngine) module is designed for performing 
the necessary bidirectional transformations between the 
photocoordinate system and the ground coordinate system 
(terrain) (figure 6). Using this transformation coordinate 
schema also allows for the transformation between an 
oriented individual photogram and orthoimage or map, and 
vice versa. That way, all the vector information collected in a 
photogram, photogrammetric model or orthoimage can be 
shared. 
  
  
  
  
  
OrtoMotor 
Photocoordinate Ground Coordinate 
system system 
Coordinate 
transformation 
VECTOR « » VECTOR 
Orientation 
DEM 
PHOTOGRAM 4 > ORTHOIMAGE 
Differential 
rectification 
  
  
  
  
  
Figure 6. OrtoMotor coordinate transformation schema 
Using the OrtoMotor module, it is possible to use the 
OrtoCaptor module even though an orthoimage is not 
available. OrtoMotor can generate an orthoimage in a real- 
time process by using differential rectification method with 
the orientation parameters and the digital elevation model of 
the desired area. 
OrthoMotor module allows for the use of digitized 
photograms and a digital elevation model in order to capture 
3D data, this operation is made using the FotoCapture 
module. The characteristics and operation of this module are 
similar to the above mentioned modules.