Web Map Service
This page describes our work developing Web Map Services based on Web Service standards.
OGC GIS VISUALIZATION WEB SERVICES
Geographical Information Systems (GIS) introduce methods and environments to visualize, manipulate, and analyze geospatial data. The nature of the geographical applications requires seamless integration and sharing of spatial data from a variety of providers. To solve the interoperability problems, the Open Geospatial Consortium [(OGC)] has introduced standards by publishing specifications for the GIS services. OGC is a non-profit, international standards organization that is leading the development of standards for geographic data related operations and services. OGC has variety of contributors from different areas such as private industry and academia to create open and extensible software application programming interfaces for GIS. Our GIS Visualization Web Services are OGC compatible.
GIS services, such as defined by the OGC, are part of a larger effort to build distributed systems, such as Grids, around the principles of Service Oriented Architectures (SOA) Media:gis-soa.pdf. Such systems unify distributed services through a message-oriented architecture, allowing loose coupling, scalability, fault tolerance, and cross-organizational service collections. Web Service architectures are a common implementation of SOA ideals, and Grid computing has converging requirements. By implementing Web Service versions of GIS services, we can integrate them directly with scientific application grids.
* Creating WMS Client for the Geophysics Applications * Creating OGC-WMS providing visualization services over o HTTP GET o HTTP POST o and SOAP protocols * Chaining of GIS Visualization and Geophysical Application servers in SOA. * Streaming Video and Map Services * Collaborative WMS o Static Map Images o Streaming Video Maps -for the time series data. o Providing various video streaming formats for + AccessGrid + GlobalMMCS audio-video collaboration sessions. * Using high performance, fault-tolerant messaging middleware system, Naradabrokering, for the message exchange between distributed and chained GIS Web Services.
WMS Web Services Description File : WMSServices.wsdl
You can create your own WMS clients by using this Web Service Description file.
Web Map Server Resources
|Visualization Related Projects in CGL||Other Related Projects in CGL|
|Community Grids Lab (CGL) Links||Standard Bodies|
WMS Interactions with Other Services
The table below summarizes the interactions between the WMS and other Web Services.
Keeps geographic data and serves opon requests from clients. Clients to WFSs are WMSs and other WFSs (in case of cascading WFS). WFSs provide vector data encoded in GML (Geographic Markup Language). GML is an XML encoding for the transport and storage of geographic information.
Keeps the list of active WFS web-service addresses. Provides interfaces to make requests to find the most appropriate WFS to get required feature data to display on the map.
See also "Applications" below for concrete examples.
Schema Files used in the Project
The table below summarizes the XML schemas that we use.
|Original OGC OpenGIS Schema Files||
Official standard schema files defined by OGC, among these are, WMS, WFS, WCS, SLD, GML, etc.
|One of the OGC schemas -WMS- UPDATED||
In some portion of the project implementation we have preferred to use Castor generated java source files. Castor is a data binding framework. To solve some castor related bugs we have made some changes to the schema files.
|Schemas for Service Request Objects||
Request instances are created according to these schemas. These requests are getCapabilities, getMap and getFeatureInfo. OGC WMS supports these three main service requests.
More extensive examples and documentation can be found at http://www.servogrid.org/slide/iSERVO/SERVO/SERVOTechDocuments/SERVOTechReportAll.pdf.
Some Geophysics Applications to which our visualization system is integrated.
- (Darft Technical Document) Ahmet Sayar, Galip Aydin, Hasan Bulut, Geoffrey Fox and Marlon Pierce, "Distributed Web Mapping and Streaming Map Movie Services".
- SERVO Draft Technical Documet. All the related projects are included.
- SERVO Draft Report Related to WMS and WMS Client Mapping Servers.
- Integrating AJAX Models with GIS Visualization Web Services.
- GIS-SOA, Geographic Information Services from Service Oriented Architecture view point.
- Ahmet Sayar, OGC Compatible Service Based GIS Visualization (WMS), Los Alamos, NM, August 2005.
- Generic Integration architecture for Google Maps and OGC Web Feature Services (WFS).
- Generic Integration architecture for Google Maps and OGC Web Map Services (WMS).
- Typical Scenario for the Pattern Informatics Application.
- Web Service based OGC Web Mapping Services (WMS) architecture and implementations.
- Pattern Informatics geophysics applications WMS Client demo snapshots for the seismic data from Turkey and Japan. PI server takes the required parameters from the user to calculate future earthquake probability values for each seismic point and return the result as GML. Returned GML is processed and geometry values are extracted. Geometry values are interpreted in different colors according to their values and plotted on the map.
- IEISS geophysics applications WMS Client demo snapshots for the electric-power and natural-gas feature data. IEISS server takes the parameters and map data, calculates outage area and returns outage area as GML. This returned outage area data in GML is rendered in pictorial format such as jpeg and overlaid on the map.
- WMS Client snapshots with California Fault data and GetFeatureInfo properties. One snapshot from the portal version of WMS Client.
- Some snapshots displaying capability of integration of Google Maps with Web Service based Web Feature Services (WFS). Same generic integration interface can be used for the other types of WFSs. Demo is done with California Fault and World Seismic feature data.
- Some snapshots displaying capability of integration of Google Maps with Web Service based Web Map Services (WMS). Same generic integration interface can be used for the other types of WMSs. Demo is done with electric power and natural-gas feature data.
* Download OGC Compatible Web Map Server ( OGC-WMS ) (API).
* Download Generic Extendable GIS-WMS Client (API). * Download Google-WFS Integration Client (API). * Download Google-WMS Integration Client (API).
Running Map Movies
Additional Setting at the Server Side to be able to run map movies :
* Download and install jmf-2.1.1 jmf downloads. * After instaling, go to program directory and, * Replace the jmf.jar in the jmf lib directory with this one Media:jmf.jar. * Download this exe file Media:CodecPlugIn.zip and run it on your machine.
* Run your newly installed JMStudio, and Click on <File><Open RTP Session> * Enter the values of Address, Port and TTL values. * Sample values corresponding above parameters <233 2 171 233> <59914> <16> * WMS Server automatically publishes its movie streams to these port and multicast IP. * In the future it will be user defined from the user interf