No difference is made between bands and annotation channels 
upon image analysis, that is annotation channel contained 
data is treated as if it were image data. Hence, bands as 
well as annotation channels are called video channels. The 
following section deals with pattern channels, therfore 
it is just for the sake of completeness mentioning here 
that any analysis procedure using video channels may be 
restricted to pixels selected by pattern channel contained 
patterns. 
     
      
  
1 . Individual 
Fi g. 4: ; planes each 
Annotating providing 
; one byte or 
pixel- d one word 
i t : per pixel 
oriente per nix 
auxiliary 
informa- 
tion. 
channeis 
  
  
auxiliary channels 
pn 
annotation pattern 
channels channels 
+ 
Crete 
video channels 
Image 
Data 
  
  
Unfortunately, space does not permit discussing record 
structures. In spite of this the following considerations 
may illustrate the flexibility of the concept. 
It follows from the previous explanations that BCL- 
records may be regarded as a special case of annotating. 
Hence, image data logically become annotations which 
makes the model gaining in generality. 
It is possible to set up a DAI which does not contain 
image data. E.g. this may be useful upon 
- preprocessing with respect to saving direct-access 
storage space, 
- establishing thematic maps where there often is no 
image data at all. 
On the other hand in section 2 powerful tools for image 
data manipulation have been required to be part of a