1) The document discusses a presentation on the Web Processing Service (WPS) standard. WPS defines how geospatial processes can be published, described, and executed over the web. 2) WPS version 1.0 specifies operations for getting process descriptions, executing processes, and managing asynchronous executions. WPS version 2.0 adds new operations for managing process executions. 3) Examples show how WPS can be used for simple GIS processes, image processing workflows, and chaining multiple processes together across different servers.

1. Jérôme Gasperi
Web Processing Service
Séminaire Innovation PS
Toulouse, France - 1er
juillet 2014

2. Interoperability
What it means, Why it matters
Open Geospatial Consortium
Web Processing Service
What is WPS ?
WPS 1.0
WPS 2.0
WPS in action
Simple GIS processing
Image processing
Chaining WPS
What's next ?

3. Interoperability
What it means, why it matters

6. ~7000since 1957

7. We need to standardize !

8. format | description | access
files metadata services
Known and readable !
(ex.. JPG,TIF, HDF, etc.)
A structured (e.g. XML) and
standardized (e.g. ISO 19115) description
OGC Web services
W*S

9. INTEROPERABILITY
format | description | access
files metadata services
Known and readable !
(ex.. JPG,TIF, HDF, etc.)
A structured (e.g. XML) and
standardized (e.g. ISO 19115) description
OGC Web services
W*S

10. Simple Complex
Requirements not supported
Low harmonization
Few benefits
Too simple
Difficult to implement
High costs
Substantial benefits to few users
Too complex
The right level of Interoperability
?

11. Interoperability
Open Geospatial Consortium

12. The Open Geospatial Consortium (OGC) is an international organization
originated in 1994 which encourage development and implementation
of open standards for geospatial content and services, GIS data
processing and data sharing.

13. 479members on july, 1st 2014

14. Maps
WMS
Vectors
WFS
Data
WCS
Metadata
CSW
Processes
WPS
OGC Web services

15. Maps
WMS
Vectors
WFS
Data
WCS
Metadata
CSW
Processes
WPS
OGC Web services

16. Web Processing Service
What is WPS ?

17. WPS is an OGC standard that defines how to publish, describe and
execute geospatial processes

18. The WPS interface standardizes the way processes and their inputs/
outputs are described, how a client can request the execution of a
process, and how the output from a process is handled.

19. WPS does not specify the kind of processes that could be implemented
as a web service. Instead, it specifies a generic mechanism that can be
used to describe and web-enable any sort of geospatial process

20. WPS aProcessingWeb application

21. Web Processing Service
WPS 1.0 (Current standard)

22. Publish Describe Execute

23. 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
of one or more
executed by the service. This description
includes the
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
implemented by a server, using the
input parameter values provided and
returning
Inputs can be included directly in the
Execute request, or reference
accessible
Execute
3

24. <wps:Capabilities service="WPS" xml:lang="en-EN" version="1.0.0" updateSequence="1352815432361">!
<ows:ServiceIdentification>!
[...Service information i.e. title, abstract, keywords, etc...]!
</ows:ServiceIdentification>!
<ows:ServiceProvider>!
[...Provider information i.e. name, adress, phone, etc...]!
</ows:ServiceProvider>!
<ows:OperationsMetadata>!
[...URLs to GetCapabilities, DescribeProcess and execute services...]!
</ows:OperationsMetadata>!
<wps:ProcessOfferings>!
<wps:Process wps:processVersion="1.0.0">!
<ows:Identifier>urn:ogc:cstl:wps:otb:classification</ows:Identifier>!
<ows:Title>Classification</ows:Title>!
<ows:Abstract>Performs an image classification</ows:Abstract>!
</wps:Process>!
[...]!
</wps:ProcessOfferings>!
<wps:Languages>!
[...]!
</wps:Languages>!
<wps:WSDL xlink:href=""/>!
</wps:Capabilities>!
GetCapabilities http://mon.serveur.com/wps?service=WPS&request=GetCapabilities

25. 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
implementation, and
operations
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
implemented by a server, using the
input parameter values provided and
returning
Inputs can be included directly in the
Execute request, or reference
accessible
Execute
3

26. <wps:ProcessDescriptions xmlns:gml="http://www.opengis.net/gml" xmlns:xlink="http://www.w3.org/1999/
xlink" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:wps="http://www.opengis.net/wps/1.0.0"
xmlns:ows="http://www.opengis.net/ows/1.1" service="WPS" version="1.0.0" xml:lang="en-EN">!
<ProcessDescription storeSupported="true" statusSupported="true" wps:processVersion="1.0.0">!
<ows:Identifier>urn:ogc:cstl:wps:otb:classification</ows:Identifier>!
<ows:Title>Classification</ows:Title>!
<ows:Abstract>Performs an image classification</ows:Abstract>!
<DataInputs>!
[...Standardized description of ComplexData, LiteralData or BoundingBoxData...]!
</DataInputs>!
<ProcessOutputs>!
[...Standardized description of ComplexOutput, LiteralOutput or BoundingBoxOutput...]!
</ProcessOutputs>!
</ProcessDescription>!
</wps:ProcessDescriptions>!
DescribeProcess http://mon.serveur.com/wps?service=WPS&request=DescribeProcess&identifier=urn:ogc:cstl:wps:otb:classification
storeSupported If set to true, process is launched asynchronously - acknowledgment is immediately sent back by the server and the
process is executed in background. Otherwise, process is launched synchronously - client holds on until the process is
finished and result is sent back (this could lead to timeout if process is too long)

27. 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
implementation, and
operations
supported by that implementation
Publish
1
DescribeProcess
The DescribeProcess operation allows
WPS clients to request a full
of one or more
executed by the service. This description
includes the
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

28. <wps:ExecuteResponse xml:lang="en" service="WPS"
serviceInstance="http://mon.serveur.com/wps/wps?"!
statusLocation="http://mon.serveur.com/wps/wps?request=GetExecutionStatus&executionId=5e59-6dfe"!
version="1.0.0" xmlns:wps="http://www.opengis.net/wps/1.0.0"!
xmlns:ows="http://www.opengis.net/ows/1.1" xmlns:xlink="http://www.w3.org/1999/xlink">!
<wps:Process wps:processVersion="1.0.0">!
<ows:Identifier>urn:ogc:cstl:wps:otb:classification</ows:Identifier>!
<ows:Title>Classification</ows:Title>!
<ows:Abstract>Performs an image classification</ows:Abstract>!
</wps:Process>!
<wps:Status creationTime="2013-01-09T16:17:08.262Z">!
<wps:ProcessAccepted>Process accepted</wps:ProcessAccepted>!
</wps:Status>!
</wps:ExecuteResponse>!
!
Execute http://mon.serveur.com/wps?service=WPS&request=execute POST data+
statusLocation Server updates the content of statusLocation url regarding the processing progress. Once finished, status is set to
<wps:ProcessSucceeded>.As a consequence, the Web client needs to periodically call the statusLocation url to determine
the end of the processing

29. The major flaw in WPS 1.0 is the lack of true asynchronous process
management...There is no way to cancel a launched process !

30. Web Processing Service
WPS 2.0 (The next step)

31. WPS 2.0 adds process management operations - Dismiss, Pause, Resume
and GetStatus. This set of operations is a must have to deploy
asynchronous WPS - especially in the

32. GetStatus
The GetStatus operation allows WPS
clients to query the status of an
asynchronously executed job
Check
4
GetResult
The GetResult operation allows WPS
clients to query the result of a finished
processing job. It is used in conjunction
with asynchronous execution
Retrieve
5
Dismiss
The dismiss extension allows a client
to cancel a job execution. The
dismiss operation is a job control
operation. Its availability is indicated
p e r p r o c e s s u s i n g t h e
j o b C o n t r o l O p t i o n s i n t h e
P r o c e s s S u m m a r y a n d t h e
ProcessOffering structures.
Abort
6

33. Pause
The Pause operation allows clients to
pause an asynchronous execution
request of a Process. Depending of
the state of the Processing Job, its
execution would not start or being
paused. On successful pause, updated
status is sent back with the state
processPaused
Pause
7
Resume
The Resume operation allows clients to
resume the asynchronous execution
request of a Process in the sense of the
Processing Job would be eligible again for
execution. On successful resume,
updated status is sent back with the state
set to the state that Processing Job had
when it have been paused
Resume
8

34. WPS 2.0 should be officially approved as an OGC standard in fall 2014

35. WPS in action
Simple GIS processing

36. https://vimeo.com/67288678

37. It works pretty well !

38. But what about image processing ?

39. WPS in action
Image processing - Assisted land cover classification

40. From pixel...
Remote sensing image
...to information
Land cover thematic map

41. Transferring a large volume of data is problematic
True for upload (i.e. the input image) and download (i.e. the result)
Issue...

42. Data and processes should be collocated
Processing results should be downloaded only if needed
Good option is to offer a Web service to visualize/manipulate results
...so

43. WPS aProcessingWeb application

44. mapshup Web
application
http://mapshup.info
WPSConstellation
http://www.constellation-sdi.org
Orfeo Toolbox Processing
http://orfeo-toolbox.org

45. Orfeo Toolbox Remote sensing image library
Open Source
Developped by the French Space Agency
Processing

46. Orfeo Toolbox More than 70 high level processing chains
orthorectification
segmentation
classification
etc.
Processing

47. 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)

48. Constellation
WPS
Geospatial Networking Services
OGC/ISO implementations
Multi platform (JAVA)
OpenSource
WMS WFS CSW WPS

49. mapshup Improves access to geospatial data
HTML + javascript
Based on OpenLayers and jQuery
Web
application

50. WPSWPS a
Web application
1
1 - DescribeProcess request for "Classification"
Classification process
description
2
2 - Set up MMI from process description
+Image url
Well known areas
3
3 - Execute an asynchronous "Classification" request
Land Cover
4
4 - Display result retrieved as a WMS layer
Orfeo Toolbox
mapshup
Image

51. https://vimeo.com/67288677

52. Chaining WPS
A chain of services

53. A WPS process is normally an atomic function

54. WPS
A
WPS
C
Data
B

55. WPS
A
WPS
C
Data
B
Process with then process the result withData
B
WPS
A
WPS
C

56. A Web client can be used to orchestrate a service chain that includes one or
more WPS within a federation

57. Chaining WPS
OWS-10 OGC testbed - Quality assessment and land cover services in a collaborative clouds environment

58. Note: this work is the result of the CNES/Astrium joint initiative within the
« Open Mobility » thread - Cloud Computing of the OGC OWS-10 Testbed

59. Orthorectification of raw image
!
Assess quality of the orthorectified image
in terms of geometrical accuracy
!
Compute Land Cover map from
an orthorectified image
Features

60. Client base processing chain workflow
between multiple clouds
!
Collaborative processing without raw data
acquisition transfert between clouds
!
WPS based on demand processing
!
Integration of Orfeo Toolbox library within
Constellation SDI
Key points

61. mapshup
http://mapshup.info
Constellation SDIhttp://www.constellation-sdi.org
Airbus Defense and Space WPS
WPS
WPS
Web
Client
Orfeo Toolbox
WMS CSW
http://orfeo-toolbox.org/otb/

62. Architecture browser,
everywhere
Rome,
Italy
Toulouse,
France
Montpellier,
France
WMS
WPS
WPS
Download
WMS
WPS
CSW
WMS
Raw images
Metadata
+
Reference 3D data

63. Orthorectify browser,
everywhere
Rome,
Italy
Toulouse,
France
Montpellier,
France
WMS
WPS
WPS
Download
WMS
WPS
CSW
WMS
Raw images
Metadata
+
Reference 3D data
Search catalog
1
Orthorectify raw image stored on a Terradue
infrastructure using a reference database and
processing chain located at Airbus Defense&Space
infrastructure without moving the data

64. browser,
everywhere
Rome,
Italy
Toulouse,
France
Montpellier,
France
WMS
WPS
WPS
Download
WMS
WPS
CSW
WMS
Raw images
Metadata
+
Reference 3D data
Search catalog
1
Ask for
Orthorectification
2
Orthorectify
Orthorectify raw image stored on a Terradue
infrastructure using a reference database and
processing chain located at Airbus Defense&Space
infrastructure without moving the data

65. browser,
everywhere
Rome,
Italy
Toulouse,
France
Montpellier,
France
WMS
WPS
WPS
Download
WMS
WPS
CSW
WMS
Raw images
Metadata
+
Reference 3D data
Search catalog
1
Ask for
Orthorectification
2
Compute AOIs
3
Orthorectify
Compute RPCs
Orthorectify raw image stored on a Terradue
infrastructure using a reference database and
processing chain located at Airbus Defense&Space
infrastructure without moving the data

66. browser,
everywhere
Rome,
Italy
Toulouse,
France
Montpellier,
France
WMS
WPS
WPS
Download
WMS
WPS
CSW
WMS
Raw images
Metadata
+
Reference 3D data
Search catalog
1
Ask for
Orthorectification
2
Orthorectify
Apply RPCs to
generate orthoimage4
Compute AOIs
3
Compute RPCs
Orthorectify raw image stored on a Terradue
infrastructure using a reference database and
processing chain located at Airbus Defense&Space
infrastructure without moving the data

67. browser,
everywhere
Rome,
Italy
Toulouse,
France
Montpellier,
France
WMS
WPS
WPS
Download
WMS
WPS
CSW
WMS
Raw images
Metadata
+
Reference 3D data
Search catalog
1
Ask for
Orthorectification
2
Stream orthoimage
WMS layer
5
Orthorectify
Apply RPCs to
generate orthoimage4
Compute AOIs
3
Compute RPCs
Orthorectify raw image stored on a Terradue
infrastructure using a reference database and
processing chain located at Airbus Defense&Space
infrastructure without moving the data

68. browser,
everywhere
Rome,
Italy
Toulouse,
France
Montpellier,
France
WMS
WPS
WPS
Download
WMS
WPS
Orthoimage
CSW
WMS
Raw images
Metadata
+
Reference 3D data
Assess Quality
Assess orthoimage quality
6
Assess quality of the orthorectified image stored on
Terradue infrastructure using a reference database
and processing chain located at Airbus
Defense&Space infrastructure without moving
the data

69. browser,
everywhere
Rome,
Italy
Toulouse,
France
Montpellier,
France
WMS
WPS
WPS
Download
WMS
WPS
Orthoimage
CSW
WMS
Raw images
Metadata
+
Reference 3D data
Assess Quality
Compute AOIs
Compute Errors
7
Assess orthoimage quality
6
Assess quality of the orthorectified image stored on
Terradue infrastructure using a reference database
and processing chain located at Airbus
Defense&Space infrastructure without moving
the data

70. browser,
everywhere
Rome,
Italy
Toulouse,
France
Montpellier,
France
WMS
WPS
WPS
Download
WMS
WPS
Orthoimage
CSW
WMS
Raw images
Metadata
+
Reference 3D data
Assess Quality
Stream error shift
WMS layer
8
Compute AOIs
Compute Errors
7
Assess orthoimage quality
6
Assess quality of the orthorectified image stored on
Terradue infrastructure using a reference database
and processing chain located at Airbus
Defense&Space infrastructure without moving
the data

71. Land Cover browser,
everywhere
Rome,
Italy
Toulouse,
France
Montpellier,
France
WMS
WPS
WPS
Download
WMS
WPS
Orthoimage
Learning features
CSW
WMS
Raw images
Metadata
+
Reference 3D data
Compute Land Cover
from orthoimage
(stored on cloud)
9
Compute Land Cover from orthorectified image
stored on Terradue infrastructure using CNES OTB
processing executed on Geomatys infrastructure

72. Land Cover browser,
everywhere
Rome,
Italy
Toulouse,
France
Montpellier,
France
WMS
WPS
WPS
Download
WMS
WPS
Orthoimage
CSW
WMS
Raw images
Metadata
+
Reference 3D data
Learning features
Compute Land Cover
from orthoimage
(stored on cloud)
9
Stream land cover map
WMS layer
10
Compute Land Cover from orthorectified image
stored on Terradue infrastructure using CNES OTB
processing executed on Geomatys infrastructure

73. https://vimeo.com/90131217

74. What’s next ?
GSCB - Federated Project Pilot - WPS for the European Ground Segments

75. CNES
DLR
ESA
Dream
FedEO
WPS
OTB
OpenSearch
Landsat
Dissharm
Take 5
SPOT 4
Landsat 8
OpenSearch
TerraSar-X
Supersite
WMS
Search
Search
Visualize
Process
1
1
2
3
Architecture
Federated Project Pilot - GSCB

76. https://vimeo.com/98979095