Open Geospatial Consortium
OGC Doc 09-15908-171
CR-Form-v3
CHANGE REQUEST
SensorML/
SweComm
oni
ng
CR
09-159 rev-
Current version: 07-122r2 For HELP on using this form, see bottom of this page or look at the pop-up text over the symbols.
Proposed change affects: AS Imp Spec X Best Practices Paper Other
Title: Enhancement of Encodings
Source: University of Muenster, Institute for Geoinformatics (IfGI)
Work item code: Date: 1016.11.09
Category: C
Use one of the following categories:
F (Critical correction)
A (corresponds to a correction in an earlier release)
B (Addition of feature),
C (Functional modification of feature)
D (Editorial modification)
Detailed explanations of the above categories can be found in the TC Policies and Procedures.
Reason for change: The parameterization of the encoding blocks is limited.
BinaryBlock/member only allows the definition of DataBlocks with a static length. TherforeTherefore, it is not possilbepossible to describe a binary block with an dynamic length, like such as an jpeg image. The parameterization of Block and Component should be extended. An optional attribute 'bitLengthRef' and 'blockLengthRef' could solve the problem. The encoding should be the same
likeas the 'ref' attribute.
XMLBlock encoding:
The definition of XMLBlock is insufficient for parsing XML documents.
Therefore, the XMLBlock encoding structure should be changed. It should be
extendendextended with 0...n XMLElements. These elements coudlcould have an xpath and ref attribute. The xpath attribute specifies the XML element/value from the given XML Document where the ref value specifies the mapping.
The OGC Technical Committee Policies & Procedures 05-020r3
Consequences if
not approved:
Clauses affected: 8.5.2, 8.5.5
Other specs Other core specifications
Affected: Abstract specifications Best Practices Document
Supporting Doc.
Other comments:
Status
Disposition
11
Example XMLBlock:
<xs:element name="XMLBlock"> <xs:complexType>
<xs:complexContent>
<xs:extension base="swe:AbstractEncodingType"> <xs:sequence>
<xs:element name="member" maxOccurs="unbounded"> <xs:complexType>
<xs:element name="XMLElement"> <xs:complexType>
<xs:attribute name="ref" type="xs:token" use="required"/> <xs:attribute name="xpath" type="xs:token" use="required"/> </xs:complexType>
</xs:element> </xs:complexType> </xs:element> </xs:sequence> </xs:extension> </xs:complexContent> </xs:complexType> </xs:element>
