position in one monoscopic image. Two-dimensional image coordinates can be transformed to ground coordinates 2-D to 3-D only when additional information is supplied in an
associated GroundShape object. This additional information can take the form of an elevation surface, elevation model coverage, or other ground shape and position data. This additional
data is provided by or stored in more specific subclasses of this class.
Superclass: none Stereotype: interface
Associations:
used by 0.. ImageGeometryTransformation
Attributes: none Operations:
intersection ray: Sequence CoordinatePoint: CoordinatePoint Compute the ground position at which the specified imaging ray intersects the ground shape
data. The imaging ray is defined by a list of two or more points lying along that ray. absoluteAccuracy point: CoordinatePoint: CovarianceMatrix
Obtain absolute position error estimates for the specified ground position previously determined. This elevation accuracy data is in the form of the applicable elements of a
covariance matrix for the ground position where the imaging ray intersects the GroundShape.
4.1.17. Class Name: ElevationSurface
Package Class Belongs to: Image Transformations Documentation:
This service class provides access to the elevation of a smooth surface being used to define the approximate shape and position of the surface visible in an image.
Subclasses:
Subclasses are expected to be defined using different elevation surfaces, such as horizontal plane, tilted plane, and spheroid. The subclasses support identical interfaces except for any
parameters needed by different forms of elevation models.
Superclass: GroundShape Stereotype: interface
Associations: only inherited associations
Attributes: none Operations:
only inherited operations
4.1.18. Class Name: ElevationModel
Package Class Belongs to: Image Transformations Documentation:
This service class provides access to an elevation model coverage being used to define the approximate shape and position of the surface visible in an image. This class is expected to
use an OGC coverage object or to be a coverage object.
Subclasses:
Subclasses are expected to be defined using different forms of elevation model, such as grid elevation, TIN, and 3-D feature geometries. The subclasses support identical interfaces except
for any parameters needed by different forms of elevation models.
Superclass: GroundShape Stereotype: interface
Associations: only inherited associations
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Attributes: none Operations:
only inherited operations
4.1.19. Class Name: ShapeModel
Package Class Belongs to: Image Transformations Documentation:
This service class provides access to a ground shape model being used to define the approximate shape and position of the surface visible in an image.
Subclasses:
Subclasses are expected to be defined using different forms of additional data, such as IFSAR and radar or laser profiles. The subclasses support identical interfaces except for any
parameters needed by the different forms of shape models.
Superclass: GroundShape Stereotype: interface
Associations: only inherited associations
Attributes: none Operations:
only inherited operations Note: The following classes, in subsections 4.1.20 through 4.1.27, are intended to be essentially the
same as the classes with the same names in the Transformation package of Topic 2. The descriptions of these classes are included here for easy reference by readers of this document. Some
of the text descriptions have been edited in an attempt to make them more understandable or more precise.
4.1.20. Class Name: CoordinateTransformation
Package Class Belongs to: Coordinate Transform Documentation:
This service interface transforms a coordinate point position between two different coordinate reference systems. A coordinate transformation object establishes an association between a
source and a target coordinate reference system, and provides operations for transforming coordinates in the source coordinate reference system to coordinates in the target coordinate
reference system. These coordinate systems can be ground or image coordinates. In general mathematics, transformation is the general term for mappings between coordinate systems
see tensor analysis.
For ground coordinate points, if the transformation depends only on mathematically derived parameters as in a cartographic projection, then this is an ISO conversion. If the
transformation depends on empirically derived parameters as in datum transformations, then this is an ISO transformation.
Superclass: none Realizes Interfaces:
PointTransformation ListTransformation
TransformationWithAccuracy Note: The use of realization is similar to but not equal to inheritance. An Interface does not
constitute a complete class definition, but defines some basic class-like behavior, such as a set of attribute, association, andor operation signatures that form a logically consistent group. In
this model, realization is used to logically group signatures into three functionally related groups:
•
transformations that transform one point at a time
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•
transformations that transform a list of points at a time
•
transformations that determine the accuracy of transformed points In any implementation of this model, these 3 groups shall be handled as units, either
implementing all of the operations in a group or none of them.
Stereotype: interface Associations:
from 1 SpatialReferenceByCoordinates in association: source
to 1 SpatialReferenceByCoordinates in association: target
used by 0.. ConcatenatedTransformation
Attributes:
transformationName: Name This attribute is the identifier of this coordinate transformation.
domainOfValidity: GM_Object The domainOfValidity attribute is a geometry that defines the geographical or image region
where this Coordinate Transformation object is appropriate to use. The coordinate reference system of this geometry may be the source, target, or any standard coordinate reference
system. When image coordinates are the source SpatialReferenceByCoordinates, the coordinate reference system will usually be the image coordinates reference system.
This OGC geometry object supports the GM_Object interface. The GM_Object interface, as described in Topic 1: Feature Geometry, includes operations that will check whether or not a
specified point or geometry is spatially within the domain of this GM_Object.
Operations:
inverse : CoordinateTransformation This operation returns another CoordinateTransformation object that reverses the actions of
this CoordinateTransformation object. The target of the inverse transformation is the source of the original, and the source of the inverse transformation is the target of the original. Using the
original transform followed by the inverse transform will result in an identity map on the source coordinate space, when allowances for error are made.
4.1.21. Class Name: PointTransformation
