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acts as a broker and performs load balancing of multiple 
requests over one or more service provider machines. Service 
providers are the work horses of the system that perform the 
processing on request. These are multi-threaded and on a multi- 
CPU or multi-core computer environment enable the full 
processing power to be utilized. Combined with the optimized 
data access and very efficient algorithms, ArcGIS Image Server 
can rapidly generate orthoimage products. 
Another feature added to ArcGIS Image Server is the Derive 
Images tool. This acts as a special client that takes a list of 
required images as input including their spatial reference 
system, extents, resolution, and output format. The Derive 
Images tool is capable of making multiple simultaneous 
requests. Combined with the distribution of these requests by 
the server of multiple cores and machines, enabling very high 
production rates. 
9. CONCLUSION 
ArcGIS Image Server, through its database-centric management 
approach and ability to generate image products on demand, 
enables workflows to be optimized and removes bottlenecks 
inherent in linear production workflows. The server can be used 
to dynamically server imagery products to large numbers of 
users as well as form the base for the generation of cached map 
services. The fast and optimized processing combined with the 
removal of intermediate products being written to disk results in 
very high production rates with higher image quality through 
reduced resampling.