Web Processing Service

Toulouse, France - 2013.05.30

Centre de Compétences Techniques "Cloud Computing et Big Data"

WPS is an OGC standard which defines interfaces to publish, describe and execute geospatial processes

The Orfeo Toolbox (OTB - http://www.orfeo-toolbox.org/) is an Open Source Remote Sensing Image Processing software library developed by CNES. The aim of the toolbox is to gather a large number of state of the art algo- rithms for building processing chains for satellite images. Using the constellation server (http://www.constellation-sdi.org/), we exposed the main OTB processing chains as Web Processing Services (WPS). The WPS provides rules for standardizing inputs and outputs for invoking geospatial processing services. These services are managed from a web browser using the mapshup web client (http://mapshup.info). mapshup supports both synchronous and asynchronous processes and offers direct visualisation of results. The whole system provides user a complete and comprehensive image processing chain to produce land cover classification from satellite orthoimagery.

With an update to WPS 2.0, this chain should fit well to a Cloud architecture

Transcript

1. Jérôme Gasperi Web Processing Service CCT SIL - Cloud Computing IAS - Toulouse, France - May 30th, 2013
2. Web Processing Service Example - Land Cover Classification WPS on the cloud What's next
3. WPS Web Processing Service
4. WPS is an OGC standard which defines interfaces to publish, describe and execute geospatial processes
6. GetCapabilities The GetCapabilities operation p r ov i d e s a c c e s s t o g e n e r a l information about a live WPS implementation, and lists the operations and access methods supported by that implementation Publish 1
7. GetCapabilities The GetCapabilities operation p r ov i d e s a c c e s s t o g e n e r a l information about a live WPS implementation, and lists the operations and access methods supported by that implementation Publish 1 DescribeProcess The DescribeProcess operation allows WPS clients to request a full description of one or more processes that can be executed by the service. This description includes the input and output parameters and formats and can be used to automatically build a user interface to capture the parameter values to be used to execute a process Describe 2
8. GetCapabilities The GetCapabilities operation p r ov i d e s a c c e s s t o g e n e r a l information about a live WPS implementation, and lists the operations and access methods supported by that implementation Publish 1 DescribeProcess The DescribeProcess operation allows WPS clients to request a full description of one or more processes that can be executed by the service. This description includes the input and output parameters and formats and can be used to automatically build a user interface to capture the parameter values to be used to execute a process Describe 2 Execute The Execute operation allows WPS clients to run a specified process implemented by a server, using the input parameter values provided and returning the output values produced. Inputs can be included directly in the Execute request, or reference web accessible resources Execute 3
9. Example WPS for assisted land cover classification
10. From pixel... Remote sensing image
11. From pixel... Remote sensing image ...to information Land cover thematic map
12. WPS a Processing Web application
13. mapshup Web application http://mapshup.info WPS Constellation http://www.constellation-sdi.org Orfeo Toolbox Processing http://orfeo-toolbox.org
14. Orfeo Toolbox Remote sensing image library Open Source Developped by the French Space Agency Processing
15. Orfeo Toolbox More than 70 high level processing chains orthorectification segmentation classification etc. Processing
16. Orfeo Toolbox More than 70 high level processing chains orthorectification segmentation classification etc. Processing Supervised learning (land cover is computed from a set of "well known areas" given by user) Based on SVM (http://en.wikipedia.org/wiki/Support_vector_machine)
17. Constellation WPS Geospatial Networking Services OGC/ISO implementations Multi platform (JAVA) OpenSource WMS WFS CSW WPS
18. mapshup Improves access to geospatial data HTML + javascript Based on OpenLayers and jQuery Web application
19. mapshup Supported data sources WMS WFS CSW WPS OpenSearch etc. Flickr Youtube GeoRSS KML Wikipedia Google maps Bing maps OpenStreetMap MapBox WMTS Web application
20. mapshup Supported data sources See WPS demo https://vimeo.com/67288678 WMS WFS CSW WPS OpenSearch etc. Flickr Youtube GeoRSS KML Wikipedia Google maps Bing maps OpenStreetMap MapBox WMTS Web application
21. WPS a WPS a Web application 1 1 - DescribeProcess request for "Classification" Classification process description 2 2 - Set up MMI from process description + Image Well known areas 3 3 - Execute an asynchronous "Classification" request Land Cover 4 4 - Display result retrieved as a WMS layer Orfeo Toolbox mapshup
22. https://vimeo.com/67288677
23. WPS on the cloud OWS-10 OGC testbed - Orthorectifying images hosted by a cloud infrastructure using WPS standard
24. WMS Web Client mapshup EU Cloud WPS Orthorectification CNES - Orfeo Toobox WMS WPS Assess Quality Improve Quality Astrium Pléiades sample data
25. Landsat Landsat Landsat 3. Click on '+' to process a new orthorectification. Process parameters are set by user and sent to an asynchronous WPS orthorectification process located on the 2. Multiple orthorectified images (i.e. processed with different parameters) can be associated to a raw image Landsat 4. Orthorectified image quality can be checked through "Assess Quality" WPS process located on the Result is displayed within the map as a WMS quality layer stored on the 1. Select raw image to orthorectify within CSW catalog located on the Laat
26. What's next WPS 2.0
27. The major flaw in WPS 1.0 is the lack of true asynchronous process management...There is no way to cancel a launched process ! WPS 2.0 addresses this issue by defining a set of process management operations - Cancel, Stop, Resume and GetStatus. This set of operations is a must have to deploy asynchronous WPS on the cloud. The WPS 2.0 should be an official OGC standard by the end of 2013.
28. https://speakerdeck.com/jjrom/web-processing-service jerome.gasperi@cnes.fr