Datacubes at your fingertips - the Web Coverage Processing Service (WCPS) standard represents OGC's high-level analytics language for Big Earth Data. To ease learning it we provide a manual and tutorial.
This WCS / WCPS showcase is powered by rasdaman, the pioneer Array Database. Its scalable array processing capabilities tie seamlessly into standard tools and in fact have shaped Big Data standards.
Goal of this site is to showcase standards-based services on Big Earth Data, in particular spatio-temporal coverages, which can be used by participants in the PARSEC Accelerator program. The service is implemented using the rasdaman Big Array Analytics engine.
Coverage data are digital representations of space/time varying phenomena, modelled as spatio-temporal regular and irregular grids, timeseries, point clouds, and general meshes. They unify representation and handling of 1-D sensor time series, 2-D satellite imagery, 3-D x/y/t image time series and x/y/z geoscientific models, 4-D x/y/z/t climate and ocean data sets, but also non-gridded data like point clouds, TINs, and other meshes.
While (tentatively) many standards allow to serve out coverages, the OGC WCS suite provides the most versatile and functionaly rich service portfolio. For example, a WFS can only deliver a complete coverage whereas WCS and WCPS allow subsetting, format encoding, and processing.
The modular WCS suite consists of a Core (mandatory for all implementations) which only defines subsetting (i.e., trimming and slicing) oc verages as well as their format encoding. Extensions (optional to implement) add further functionality facets in a compatible, coherent manner.
The OGC OGC Web Coverage Processing Service (WCPS) Language standard defines OGC's coverage analytics language. WCPS unleashes open, flexible Web access to sensor and observation data archives for navigation, extraction, aggregation, and analysis.
The OGC Web Coverage Processing Service (WCPS) Language Interface Standard (OGC document 08-068r2) defines a protocol-independent language for the extraction, processing, and analysis of multi-dimensional gridded coverages such as sensor, image, or statistics data. Services implementing this language provide access to original or derived sets of geospatial coverage information, in forms that are useful for client-side rendering, input into scientific models, and other client applications. The WCPS standard is available from OGC as document 08-068r2.
An embedding of the protocol-neutral WCPS language into WCS is given by defining an additional WCS request type, ProcessCoverages. Further, there is an embedding specification for WCPS over WPS as carrier protocol (OGC document 09-045).
Array Databases allow storing and querying massive multi-dimensional arrays, such as sensor, image, simulation, and statistics data appearing in domains like earth, space, and life science.
rasdaman ("raster data manager") has pioneered the field of array databases [VLDB 1994, VLDB 1997, SIGMOD 1998, VLDB 2003] and today is sets itself apart by its flexibility, performance, and scalability [SSDBM 2014, SIGMOD DanaC 2014, IJDE 2015]. Rasdaman embeds itself smoothly into relational databases, but can also run standalone on the file system. In fact, rasdaman still is the first fully implemented, operationally used system with an array query language and optimized, multi-parallel processing engine with unprecedented scalability. Known rasdaman database sizes exceed 100 TB; with EarthServer, intercontinental fusion of Petabyte datacubes is being established.
The concepts implemented in rasdaman have massively shaped Big Data standards, such as
See Them in Action
...and proceed to the demonstration area!