Web-Based Geoprocessing and Workflow Creation for Generating and Providing Remote Sensing Products

Abstract

With the implementation specification of the Web Processing Service (WPS), a standard to process spatial data on the web is available from the Open Geospatial Consortium (OGC). This new possibility in web-based information systems allow an interoperable processing of different data based on service-oriented architectures. This paper describes requirements and an implementation for web-based processing and workflow creation to generate and provide remote sensing products like fire hotspot points and land surface temperatures based on NASA MODIS data. Therefore, a WPS as well as service chains to process these remote sensing products are implemented. PyWPS is used as WPS and tested with focus on processing remote sensing data. To chain the developed processes, software like 52° North Orchestration Engine, Apache ODE and internal software for executing processing chains and providing a workflow as WPS process are tested. A Web-GIS with open-source software was developed to manage started and finished processes, to search for available satellite data and to create processing chains interactively. An interface to retrieve and process archived data was integrated; the user of this system can search interactively for archived satellite data and process it with the developed processing services and workflows. The Web-GIS also acts as a WPS client, client for visualizing processed data and creator as well as security layer for processing chains. These developments and research work show that there is additional work to improve the WPS specification for example by adding domain-specific profiles for working with large raster data to define standardised rules for data-exchange between the processes. In the field of process orchestration, no standardised data format describing processing chains exists yet.