CC Sedona dev in the loop On Mon, Nov 20, 2023 at 17:37 Martin Desruisseaux < martin.desruisse...@geomatys.com> wrote:
> Hello Jia > > No worry for the delay. I'm often late myself. > > > Le 2023-11-20 à 05 h 56, Jia Yu a écrit : > > > the Sedona community will start to try the COG writer in late January > > or early Feb 2024. By that time, we will drop the support of Java 8 to > > be aligned with Apache SIS. > > > Thanks for the information. We can target a SIS 1.5 release in January > then. In the mean time, snapshots will continue to be pushed from time > to time on the Apache snapshot repositories. Please let me know if you > face issues. > > > > In addition, do you have any plan to implement a native Java reader > > and writer of PROJJSON string? (…snip…) We recently ran into a problem > > in Sedona GeoParquet reader and writer: no existing pure Java library > > that can read and write a CRS in PROJJSON format. However, PROJJSON > > somehow is the CRS representation required by GeoParquet spec: > > > This is under discussion. PROJJSON is currently a format which is > specific to the PROJ project, not yet a standard. However, it has been > brought to the Open Geospatial Consortium (OGC) CRS Standard Working > Group (SWG) for standardization. I'm a member of this group and attended > to the initial discussion. The group is open to standardizing that > format, but may want to do some changes if they consider that some > aspects of PROJJSON are incorrect. On the other hand, PROJ is reluctant > to allow changes because PROJJSON is already used. In an attempt to find > an agreement, the CRS SWG has updated its charter as below: > > /---- Quote from CRS SWG charter ----/ > > The new SWG work item is to define and support an encoding of the > self-contained and compact description of Coordinate Reference > Systems and Coordinate Operations through a simple JSON schema. The > draft standard delivered will be consistent with OGC Abstract > Specification Topic 2 and ISO 19111. This offers the following > advantages: > > * Provides a JSON encoding of coordinate reference systems > descriptions for use where JSON may be considered a more natural > data schema than Well Known Text. > * Ensures that a JSON schema is available that will be kept in > alignment with OGC Abstract Specification Topic 2 and ISO 19111. > * Recognizing the PROJ6 origins of the PROJJSON schema > contribution being used as the starting point of this work, > effort will be made to try to avoid compatibility issues and to > clearly document any issues identified or object names that > deviate from the original OGC Abstract Specification Topic 2 and > ISO 19111. If an unresolvable conflict is identified, OGC > Abstract Specification Topic 2 and ISO 19111 will guide the > resolution and such an issue will be clearly documented. > > /---- End of quote ----/ > > The CRS SWG has not yet started its work on a CRS JSON. In the last 10 > years, progresses in CRS SWG were done a lot thanks to Roger Lott, who > has done a tremendous amount of work in editing ISO 19111 (a.k.a. OGC > Topic 2) and 19162 (a.k.a. WKT 2). For now Roger is busy with GGXF, > which is in final stage for becoming a standard. Maybe after that, we > will see progress in CRS JSON. > > Meanwhile, GeoParquet is submitted for becoming an OGC standard, but is > not yet a standard. An OGC GeoParquet working group has been recently > created for that purpose. I joined that group as well, but did not yet > attended a meeting. I assume that the CRS representation in GeoParquet > will be a topic of some meetings. We do not know yet what will be the > group decision: will they keep PROJJSON unchanged? Wait for a CRS JSON > to be standardized before to standardize GeoParquet? Allow an > alternative encoding such as ISO 19162? > > On Apache SIS side, some JSON parsing exists in the "incubator" group of > modules. The "incubator" group contains modules that are not yet part of > Apache SIS releases, because not considered mature yet. One of them is a > "Coverage JSON" module. The experience gained there may be used for a > "CRS JSON" support later. Another incubator module of potential interest > is a Shapefile reader and writer. > > About the time frame: we applied to a GeoParquet funding made available > by OGC, with a proposal to do the development in Apache SIS. > > > https://www.ogc.org/requests/funding-available-for-creating-geoparquet-developer-resources/ > > If our submission is accepted, it would vastly speedup the development, > with at least a temporary solution for "CRS JSON" due in the time frame > of that project. If not accepted, we will probably try to do it anyway, > but it would take longer (we don't know how long). > > Martin > >
