To separate usage and design concerns, this coordinate transformation interface subset assumes that the service has already been initialized and provided with all the image support data needed to
perform these coordinate transformations. The interface subsets needed to do this are discussed below.
Because this is the most fundamental interface subset, almost all the interface operations defined later in the Abstract Model see Sections 4.1.6 through 4.1.27 are in this interface subset.
3.2.2. Import Support Data
For image coordinate transformation services, the next critical interface subset purpose is importing the image support data that is required to subsequently perform image coordinate
transformations. These interfaces are needed whenever separate software packages or systems produce and later use this image support data. This image support data includes all the
information needed to define the correct relationship between corresponding image and ground coordinates. This interface subset probably should include interfaces for exporting the image
support data for later use.
In many cases, the interface subset for importing image support data should be standardized by the OGC. Standardization is needed to allow interoperation between different software packages that
may produce and use this image support data. Standardization is also needed to support interoperation between different software packages that may need to perform coordinate
transformations for the same images. Standardization is also desirable to allow any of multiple software packages and systems to produce image support data for use by one or more image
coordinate transformation packages.
On the other hand, complete OGC standardization of an interface subset to import image support data may not be possible or not be needed for image support data whose contents are proprietary.
To separate usage and design concerns, this import data interface subset may assume that the service has already been initialized. The interface subset needed to initialize the service is discussed
below. Alternately, that interface subset might be intimately combined with this interface subset. The “Image Support Data Conversion” interface operations defined later in the Abstract Model see
Sections 4.3.6 and 4.3.7 are in this interface subset.
3.2.3. Administer Service
In general, one needed interface subset purpose is administration of the service implementation software. Such administration functions might include starting and stopping service software: a
readiness to execute, b communication connection to client software, andor c usage session by client software. Other possible administration functions include setting and checking service
operation properties, such as quality of service and service options.
To separate usage and design concerns, this interface subset may be separate from all others. Alternately, this interface subset could be partially or fully combined with the interface subset for
importing image support data see previous section.
3.2.4. Convert Accuracy Data
For image coordinate transformations, one possible interface subset purpose is conversion of accuracy data between different forms. Such conversions may be needed by clients before or after
exercising other image coordinate transformation functions. To separate usage and design concerns, this interface subset may be separate from all others.
Alternately, this interface subset could be partially or fully combined with another the interface subset.
The “Accuracy Transformations” interface operations defined later in the Abstract Model see Section 4.4.6 and 4.4.7 are in this interface subset.
3.2.5. Access Service Metadata
Another generally needed interface subset purpose is accessing metadata that describes the service implementation and interfaces. This metadata could include a variety of service metadata
categories, including service location, service access, function description, interface description, input data, output data, output data quality, changeable properties, and metadata quality. For image
coordinate transformation services, the available and useful metadata is likely to include metadata
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describing the general accuracy of the transformation, plus the identification of the specific image version supported. Both metadata retrieval and modification might be supported by this interface
subset. No specific metadata access capabilities are currently defining in the Abstract Model see Section
4, but are the subject of needed future work see Section 6.
3.2.6. Adjust Image Coordinate Transformation
