Session 1: Introduction to Geospatial Standards

• Why do we care about standards?• Agreement on syntax, information models and

interfaces lets us share information and processes.– Often not for technical brilliance (although sometimes)– For consensus and agreement

Relevant Standards Bodies: ISO/TC 211

• Technical Committee of the International Organisation for Standardisation.

• ISO is a non-governmental organisation with members in each country.

• Responsible for the geographic information series of standards.

• http://www.isotc211.org/

• Important standards for metadata (Session 2) and many others.

• Many OGC standards become ISO standards.

6709:2008 - Standard representation of latitude, longitude and altitude for geographic point locations6709/Cor 1

19129:2009 - Imagery, gridded and coverage data framework

19101:2002 - Reference model (under revision) 19130 - Sensor and data models for imagery and gridded data

19101-2:2008 - Reference model - Part 2: Imagery 19131:2007 - Data product specifications19103:2005 - Conceptual schema language (under revision)

19132:2007 - Location based services - Reference model

19104:2008 - Terminology 19133:2005 - Location based services - Tracking and navigation

19105:2000 - Conformance and testing 19134:2007 - Multimodal location based services for routing and navigation

19106:2004 - Profiles 19135:2005 - Procedures for registration of geographical information items

19107:2003 - Spatial schema 19136:2007 - Geography Markup Language19108:2002 - Temporal schema19108/Cor 1

19137:2007 - Core profile of the spatial schema

19109:2005 - Rules for application schema19138:2006 - Data quality measures (under revision as PT 19157)

19110:2005 - Methodology for feature cataloguing19110 Amd 1 under development

19139:2007 - Metadata - XML schema implementation

19111:2007 - Spatial referencing by coordinates 19141:2008 - Schema for moving features

19111-2:2009 - Spatial referencing by coordinates - Part 2: Extension for parametric value

19142 - Web Feature Service

19112:2003 - Spatial referencing by geographic identifiers

19143 - Filter encoding

19113:2002 - Quality principles (under revision as PT 19157)

19144-1:2009 - Classification Systems – Part 1: Classification system structure

19114:2003 - Quality evaluation procedures (under revision as PT 19157) 19114/Cor. 1

19144-2 - Classification Systems – Part 2: Land Cover Classification System LCCS

19115:2003 - Metadata (under revision) 19115/Cor. 1

19145 - Registry of representations of geographic point location

19115-2:2009 - Metadata - Part 2: Extensions for imagery and gridded data

19146 - Cross-domain vocabulary

19116:2004 - Positioning services 19147 - Transfer nodes

19117:2005 - Portrayal (under revision) 19148 - Linear referencing

19118:2005 - Encoding (under revision) 19149 - Rights expression language for geographic information - GeoREL

19119:2005 - Services 19119/Amd. 1

19150 - Ontology

19120:2001 - Functional standards 19151 - Logical location identification scheme

19121:2000 - Imagery and gridded data 19152 - Land Administration Domain Model (LADM)

19122:2004 - Qualifications and Certification of personnel19153 - Geospatial Digital Rignts Management Reference Model (GeoDRM RM)

19123:2005 - Schema for coverage geometry and functions

19154 - Standardization Requirements for Ubiquitous Public Access

19124 - Imagery and gridded data components 19155 - Place Identifier (PI) Architecture

191251:2004 - Simple feature access - Part 1: Common architecture (under revision)

19156 - Observations and measurements

19125-2:2004 - Simple feature access - Part 2: SQL option (under revision)

19157 - Data quality

19126:2009 - Profile - FACC Data Dictionary 19158 - Quality assurance of data supply

1912:2005 - Geodetic codes and parameters 19160 - Addressing

19128:2005 - Web Map server interface  

Relevant Standards Bodies: W3C

• World Wide Web Consortium.• International community for standards related to the web.• http://www.w3.org/• Core web standards (HTML, HTTP, XHTML, SOAP).• XML related standards (XML, XML Schema, XSLT,

XQuery).• Semantic standards (RDF, OWL, SPARQL, SKOS).• Not geospatial, but used and extended in many geospatial

standards.

Relevant Standards Bodies: OASIS

• Organisation for the Advancement of Structured Information Standards.

• International Consortium developing open standards for the global information society.

• http://www.oasis-open.org/home/index.php• Many standards relating to interoperability.• ebRIM, ebRSS.• Not geospatial, but used by some geospatial standards.

Relevant Standards Bodies: The Open Geospatial

Consortium• An international consortium of universities, private companies,

government agencies.

• Develops standards for geospatial and location based services.

• http://www.opengeospatial.org/

• Most important body for geospatial information.

• Uses and adapts standards from other groups where possible.

• Meets quarterly (in Sydney this December)

The OGC Standards Framework

• Abstract Specifications.• OpenGIS Standards.• OpenGIS Reference Model.• Best Practices Documents.• Discussion Papers.• White Papers.• OGC Interoperability Experiments.

OGC Abstract Specifications

• Platform independent abstract model.• Reference model for the development of OGC

standards.• Many become ISO/TC 211 Standards.

OGC Standards Process

Discussion PaperDiscussion Paper

Best Practices Document

Best Practices Document

SpecificationSpecification

Acceptance by Working Group Vote at TC Meeting

Acceptance by full plenary at TC Meeting or eVote(>=2 implementations)

Acceptance by eVote

Topic 0: OverviewIntroduction and Roadmap.

Topic 10: Feature CollectionsFeature Instances, Feature Schema, Project Schema

Topic 1: Feature GeometryISO 19107.

Topic 11: MetadataISO 19115 (replaces topics 9 and 11)

Topic 2: Spatial Referencing by CoordinatesModelling requirements for coordinate referencing.

Topic 12: The OpenGIS Service ArchitectureISO 19119

Topic 3: Locational Geometry StructuresAbstract models for GIS technology.

Topic 13: Catalog Services

Topic 4: Stored Functions and InterpolationAbstract models for technology, especially coverages.

Topic 14: Semantics and Information Communities

Topic 5: FeaturesDescribes geographic features.

Topic 15: Image Exploitation Services

Topic 6: Schema for coverage geometry and functions

Topic 16: Image Coordinate Transformation

Topic 7: Earth ImageryISO 19101-2, ISO 19191-2

Topic 17: Location Based Mobile Services

Topic 8: Relationships between Features Topic 18: Geospatial Digital Rights Management Reference Model (GeoDRM)

OpenGIS Standards• A document, established by

consensus, describing rules and guidelines for interfaces and encodings.

• Aimed at achieving interoperability.• Implementation, not abstract.• More technical, allow actual creation

of the interfaces

OpenGIS Implementation Specification

(Interface Standards) http://www.opengeospatial.org/standards/is

Catalogue Services SpecificationAccess to catalogue information.Multiple profiles, extension packages, discussion papers and best practice documents.

Simple FeaturesCommon architecture and interfaces for access to geographic data with OLE/COM, CORBA and SQL.

Coordinate Transformation ServiceStandard way to specify and access and coordinate transformation services.

Web Coverage ServiceRetrieval of geospatial data as coverages (space varying phenomena).

Filter EncodingXML encoding for filter expressions

Web Coverage Processing ServiceDefines a language for retrieval and processing of multi-dimensional geospatial coverages representing sensor, image, or statistics data.

Geographic ObjectsA set of abstractions for describing, rendering, and manipulating geographic objects

Web Feature ServiceRetrieval of geographic object-based features.

Grid Coverage Service (Retired)Raster analysis and processing.

Web MapServiceGeneration and retrieval of geo-registered map images.

Open Location Services (OpenLS)Interfaces for Location Based Applications.

Web Processing ServiceRules for inputs and outputs from geospatial processing services.

Sensor Observation ServiceAPI for deploying sensors and retrieving sensor data.

Web Service CommonParameters and structures that are common to all OGC web service standards.

Sensor Planning ServiceInterface for sensor querying.

OpenGIS Encoding Standards

CityGMLVirtual 3D city and landscape models.

Observations and MeasurementsAbstract model and XML Schema for Observations.

Geography Markup LanguageXML grammar for geographic features.

Sensor Model LanguageModels and XML encoding for sensors and sensor systems.

Geospatial eXtensible Access Control Markup Language (GeoXACML)

Styled Layer DescriptorSymobolization and colouring of geographic features in WMS.

GML in JPEG 2000Using GML with JPEG for geographic imagery.

Symbology Encoding

KML Transducer Markup LanguageExchange of data with sensors.

OGC Interoperability Experiments

• Projects set up by the OGC.• Parties are invited to participate.• No financial incentive usually.• Allow you to get involved with other groups

testing standards.

OGC Web Service Basics• Set of methods or operations with:

– A set of defined request parameters.– A set of defined response parameters.

• All have GetCapabilities (publish – find – bind).• Use GET or POST.

Web Map Service• GetMap method lets you ask for a map, specifying:

– Layers and display styles– Bounding box– Image format

• Returns a map• GetFeatureInfo lets you ask for basic

attributes.• Show GetCapabilities.

Try some example WMSs at:

• http://www.bgs.ac.uk/data/services/1gewms.html

• GetCapabilities shows you the layers

• GetMap shows you the map

• GetFeatureInfo shows some basic data.

Web Feature Service• GetFeature method lets you query features

specifying:– Feature types– Filter (attribute and spatial)– Other parameters (records to return etc).

• Returns GML data (more later).• Also transaction methods available.• Show GetCapabilities.

Try some example WFSs at:

• http://nsidc.org/data/atlas/ogc_services.html#WFS

• GetCapabilities shows you the layers

• GetFeature returns features in GML

• DescribeFeatureType describes the feature type (schema).

Web Coverage Service• GetCoverage method lets you ask for raster

source data, specifying:– Coverage name– Bounding box– Image format

• Returns a raster image.

• DescribeCoverage gives you basic metadata about the coverage.

Filter Encoding• An XML encoding for the OGC common

catalogue query language (abstract spec).

• Defines:– Spatial operators (e.g. disjoint, touches, contains)– Comparison operators (e.g. equalTo, like)– Logical operators (and, or, not).

• Used in many other OGC specifications (WFS, CSW).

OGC Standards: Strengths and Weaknesses

• Strengths:– Consensus, agreed view.– Used widely.– Not many alternatives.

• Weaknesses:– Sometimes not very sophisticated.– Slow to develop.– Can be driven by an influential group or individual.

Discussion

• Current use of OGC standards?

• Other standards?

• Potential for use?

Summary• There are many standards.

• The interactions and dependencies can be complicated, but most of the standards themselves are fairly simple.

• Interoperability is very difficult without them!