a system dependent number of consecutive main storage 
words. There are handlers enabling soft sector addressing 
with respect to direct-access storage files by relative 
sector addresses 0, 1, 2, ... even if the access were 
optimum only upon referencing hard sectors. Furthermore, 
these handlers provide an automatic expansion on every 
write function until an initially defined maximum size 
is encountered if space is allocated in certain granules 
rather than by being initially assigned in total, and 
the file space may be considered contiguous by the pro- 
grammer in this case. 
There is sufficient flexibility inherent in the previous 
conditions to simultaneously attain the introductory 
objectieves. If upon an implementation of PODIUM a 
particular equipment does not exactly meet these conditions 
appropriate interfacing is feasible at a reasonable 
expense. 
The basic idea upon storing and retrieving information by 
means of PODIUM is to have 
- a one-to-one mapping between digital images and certain 
direct-access storage files which are called direct- 
access images or DAI's, 
- for each image the corresponding image data and non- 
pictorial information completely stored in its DAI. 
One of the reasons is that files as they have been 
previously defined are sets of data which can be manipu- 
lated by every operating system thus providing an easy 
means of saving to tape or restoring from tape at almost 
every stage of an image analysis procedure without any 
loss of information. (Obviously this stimulates to going 
image data base.) 
storage 
A 
method 
purpose À 
   
    
  
      
     
  
  
  
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e. qm ]/ — 
  
    
  
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image window relation 
Classification of types of information.