importSupportData file: CharacterString: NameValueList Import the specified image geometry support data file. Also, check this image support data and
return a Name Value List describing any “errors” or missing data detected. exportSupportData format: CharacterString: CharacterString
Obtain current image geometry support data as a character string in the specified external format.
4.4. Accuracy Conversion Services
4.4.1. Function
The Accuracy Conversion Services convert position accuracy estimates between error covariance matrix form and Circular Error CE plus Linear Error LE or other forms. These accuracy
conversions are also applicable to linear dimensions and perhaps other accuracy estimates. When converting most other forms of accuracy data to covariance matrices, correct values will not
be known for some covariance matrix cells. Specifically, the off-diagonal cells for covariances between coordinates will not be known. As specified in Abstract Specification Topic 9: Quality, the
values of these covariance matrix cells should be null or missing. Alternately, these covariances values would be assumed to be zero.
When converting covariance matrices to other forms of accuracy data, some cells of a covariance matrix may be unknown. When this occurs, the unknown matrix cells must be handled in an
appropriate manner.
4.4.2. Service Subtypes
The expected sub-types of Accuracy Conversion Services include, but are not limited to: 1.
Convert covariance matrices to other forms: 2.
Convert 3-D covariances to CE plus LE 3.
Convert 2-D covariances to CE 4.
Convert 1-D variance to LE 5.
Convert 3-D covariances to Spherical Error SE 6.
Convert 1-D variance to Standard Deviation 7.
Convert other forms to covariance matrices: 8.
Convert CE plus LE to 3-D covariances 9.
Convert CE to 2-D covariances 10. Convert LE to 1-D variance
11. Convert Spherical Error SE to 3-D covariances 12. Convert Standard Deviation to 1-D variance
4.4.3. Result Data
The data produced by the Accuracy Conversion Services includes: 1.
Accuracy estimates in desired form is metadata for some point positions 2.
Confidence levels for output CE, LE, and SE values is metadata for CE, LE, and SE values?
4.4.4. Needed Data
The data needed for use by the Accuracy Conversion Services includes: 1.
Accuracy estimates in existing form is metadata for same point positions
The Open GIS Abstract Specification Page 39
Volume 16: Image Coordinate Transformation Services 00-116.doc
2. Selection of accuracy estimate form desired
3. Confidence levels for input CE, LE, and SE values
is metadata for CE, LE, and SE values? 4.
Accuracy conversion parameters is metadata for accuracy conversions?
4.4.5. Object Model
