digitai computer. 
  
This automated system could provide the basic 
capability for computing quality control parameters and for editing 
the image coordinates. Moreover, the potential capabilities of an 
on-line system are limited only by the size and speed of the dedicated 
general purpose computer.  Theoretically, given a computer of large 
enough capacity in the on-line system, the data ecquisition and 
data processing could be performed entirely on-line in a closed loop 
between operator, comparator, and computer. In practice, it is not 
possible to justify a large scale computer and furthermore it may not 
be desirable or advantageous to perform all computatioris in an on- 
line manner. 
The availability of an on-line system provides the analytical 
photogrammetrist with several interesting areas of research which 
include: 
a. The automatic selection of pass points for the triangulation 
solution. 
b. An investigation of a mathematical data reduction scheme 
suited to the on-line mode of operation. 
c. Quality control and data editing techniques which may be 
implemented with a digital computer. 
d. A practical and realistic algorithm for computing the 
weights of image coordinates.