Cr 
final results. It is divided into four parts: 
data aquisition 
- preliminary computations and error detection 
bundle adjustment 
prosessing and presentation 
  
Object control data 
  
Image digitizing 
Nominal construction data 
  
  
  
  
  
  
DATA BASE - Processing and 
presentation 
  
  
  
  
  
  
     
  
   
   
Preliminary Graphi 
e 
computations Bundle Control reports EUR 
Error detection adjustment tation 
  
  
  
  
  
  
  
Fig. 2 Program system 
Data aquisition 
The main task of this part is to obtain image co-ordinates from the pictures. 
The digitizing program was made to provide on-line monocomparator measure- 
ments. The operator is guided through the digitizing procedure by questions, 
menus and warnings. The fiducial marks are first read, and the operator may 
not proceed until the co-ordinates are accepted i.e. the discrepancies are 
within given limits. Double pointing is also recommended for image points. 
The double pointing is performed by first reading all points once in the se- 
quence given by the operator, and then the program will request the reading 
of each point in the opposite sequence. If the discrepancies are beyond the 
given limits, a warning is submitted, and the operator may delete readings 
or make additional readings. The mean of the accepted readings for each 
point is stored in the data base. ; 
Preliminary computations and error detection. 
This group of programs will compute orientation parameters and object co- 
ordinates using closed solution algorithms. The results are used as pre- 
liminary values in the bundle adjustment. Furthermore the programs are con- 
venient tools for interactive detection of errors. The available procedures 
are space resection and intersection, relative orientation, and orthogonal 
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