- determination of conjugate points in the images (im- - generation of a DTM (and follow-up products), 
age matching), - computation of an orthoimage. 
- calculation of the elements of exterior orientation 
(generalized bundle adjustment), 
The data flow for the processing of SPOT imagery is 
depicted in figure 1. At present, human interaction is 
only necessary for the identification and measurement 
  
- forward intersection of the conjugate points, 
Information from 
header of SPOT 
stereo scenes 
  
  
  
of the GCP. 
| SPOT stereo scenes 
  
  
  
  
Identification and 
measurement of 
GCPs in the stereo 
scenes 
  
  
[mage matching 
  
  
         
    
  
  
Selection of a 
sufficient number of 
image coordinates 
  
Ÿ 
  
  
  
GCPs in an arbitrary 
coordinate system 
  
  
Ec 
GCPs in the object 
coordinate system 
  
  
  
  
  
| Bundle adjustment 
  
  
  
3 
ES | Space intersection 
| DTM generation . 
  
  
| Visualization, quality control | 
  
  
  
One SPOT scene 
  
  
  
  
DTM follow-up products 
(contour lines, shaded 
relief, perspectives, incli- 
nation maps, ...) 
Orthophoto 
computation 
     
  
  
  
Orthophoto map 
al 
b 
Fig. 1: Photogrammetric processing of SPOT images, data flow 
466