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telemetry data in usable image products. 
The image products from CRIS (scenes of 60 km x 60 km in panchromatic or mul- 
tispectral mode) are delivered to SPOT IMAGE which has been set up for the 
purpose of marketing and distributing on a commercial basis such products. 
The present paper will describe in more details the functions and the overall 
organisation of the CRIS. Note that the same system will be installed: in 
FRANCE at TOULOUSE and in SWEDEN at KIRUNA. 
2 - CONCEPTION AND DESIGN OF CRIS 
  
CRIS has two main functions : the first one is to archive data received from 
the satellite, the second one is to preprocess data and deliver standard 
products. 
Archiving functions 
CRIS receives telemetry data from the receiving station on high density tapes 
HDDT. It receives also from the SPOT Mission Center handling data as epheme- 
ris, payload programming and datation correction parameters. Then, CRIS has 
to fulfill the following archiving functions 
- control of HDDT : content and telemetry quality, 
- Slicing of telemetry flow into elementary scenes, 
- generation of quick look films for each scene, 
- evaluation of cloud cover, v 
- creation of auxiliary data necessary for further processing, 
- sénding to SPOT IMAGE new elements to be incorporated in SPOT IMAGE cata- 
logue. 
Preprocessing functions 
The main objective of CRIS is to be able to deliver a high number of products 
within short delays. This objective leads to limit the number of different 
types of image products that can be processed by CRIS and delivered by CRIS. 
It is the role of SPOT IMAGE to make specific transformation of these pro- 
ducts to meet final user requests. The products characteristics and the pro- 
duction delay are defined in the figures here after.