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domainExtent vs gml:boundedBy (EL & OI coverages encoding)

Peter Parslow opened the following discussion topic in the Elevation subgroup, making a new proposal to encode the domain extent of (ISO 19123) INSPIRE coverages using gml:boundedBy

https://themes.jrc.ec.europa.eu/discussion/view/12877/domainextent-vs-gmlboundedby

Original description from Peter:
Given that the purpose (within the INSPIRE specification) of the ISO 19123 domainExtent attribute is to describe the spatial extent of the domain, why not implement it with gml:boundedBy? As it stands, the feature should have both a gml:boundedBy (from GML good practice) and an inspire/ISO domainExtent, containing the same geometry encoded in a different way.

Since the proposal is not only valid for Elevation coverages, but also for Orthoimagery ones (and any other INSPIRE coverages in general), please use this new discussion topic in the parent Cluster group for further discussion.

Feel free to participate!

 

  • Jordi ESCRIU

    Dear Peter,

    In my view, this telecon / webinar would be definitively useful!

    Jordi

  • Emmanuel DEVYS

    By Emmanuel DEVYS

    Jordi, Peter and all

    we (Dimitri Sarafinof and Marie Lambois) had a short analysis of the OI model, and the issues of implementation of INSPIRE extensions for OI or EL as extensions of GMLCOV that are not handled by WCS2.0.

    We fully agree with Peter Baumann that all that extension items is lost be DS based on WC2.0 technology, thus creating issues.

    We would strongly recommend that the OI/EL specification be revised / simplified in order to make it implementable with GMLCOV, with minimum level of  mandatory extension (ideally none), and to transfer the additional information which would be required in metadata (which may be multiple). This applies to OrthoimageCoverage and ElevationGridCoverage classes.

    In addition to this, for OI, the handling of voidable MosaicElement by WCS2.0 is to be questionned. Could it follow similar strategy?

    We are more sceptic on the interest of CIS1.1 (instead of GMLCOV - 09-146r2) in the close future, and expect no added value for the resolution of the issue identified by this thread for RectifiedGridCoverage, as the emergent CIS1.1 is under submission to OGC and TC211, and brings evolution for n-dimensional coverages and irregular grids. CIS1.1 is announced to be backward compatible with GMLCOV for RectifiedGridCoverage.

    Emmanuel

  • Jordi ESCRIU

    Dear Emmanuel, Dimitri & Marie,

    I totally agree with your view / approach - We should try to minimize as possible INSPIRE extensions to the plain GMLCOV structure.

    We should continue the discussion for:

    • Proposing a formal amendment of both TGs, Elevation and Orthoimagery, with the aim of minimizing INSPIRE covarage extensions.
    • Decide how to transfer the additional information to the metadata (do you explicitly refer to the 'metadata' hook from GMLCOV?) for both, Elevation & Orthoimage coverages.

    This is also quite in line with one of the outcomes of the Workshop on Transformation of Coverage-based Data Themes and WCS that we had in Barcelona at the end of September (as stated in this thread):

    5. How to proceed with some partial conceptual redundances identified between INSPIRE coverages attributes and GMLCOV components.

    An example of this redundances is identified and discussed here - 'domainExtent' vs. 'gml:boundedBy' discussion: https://themes.jrc.ec.europa.eu/discussion/view/12901/domainextent-vs-gmlboundedby-el-oi-coverages-encoding

    ...and also the aim of the last OPTION I proposed on 28th October aroung 3:47 pm.

    In fact, I propose to "analysing carefully the mapping between ISO 19123 and GML+GMLCOV" because it seem to be not clear - i.e. contradiction which Peter Parslow spotted regarding the first posts of Peter Baumann & Clemens Portele in the thread, which you (Emmanuel) also highlighted.

    Since this contradiction has been clarified by Peter Baumann (yesterday by email, today in the platform), I am much more happy with going for a solution in line with what you (Emmanuel, Dimitri & Marie) are proposing now!

    I understand that the discussion involves now other attributes as well (i.e. not only gml:boundedBy vs. domainExtent), so the discussion should continue probably in other thread (still to be decided).

    Some remaining comments:

    • Please, clarify what you are exactly proposing with the handling of voidable MosaicElement.
    • In my view, CISv1.1 is not only bringing evolution for n-dimensional coverages and irregular grids, but also an opportunity to solve some of the unclear aspects / contradictions between GML and GMLCOV (e.g. use of rangeParameters vs. fileReference to provide the URL to covarage values, as you know, spotted here) - Hence, I think that Peter Baumann's offer to have a webinar on this is useful.

    Jordi

Elevation, Ortho & Grids

Elevation, Ortho & Grids

INSPIRE Thematic Cluster Elevation, Orthoimagery, Reference systems, Geographical grids - Join this group to share your knowkledge, learn and collaborate in solving issues related to the Elevation, Orthoimagery, Reference systems and Geographical grids themes