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[netCDF #CUE-552730]: GIS data



Hi,

> Thank you so much for the fast response.
> Sigh! I hoped that netCDF can handle R-tree like data organization.
> 
> I have one more question.
> 
> Have you ever seen any examples of using netCDF4 format to package GIS data 
> files?
> By GIS data files, I mean files like, for example,
> Triangular Irregular Network,
> Point Clouds (3D),
> Shape file,
> GeoTiff (this might not be possible)

Yes, the "UGRID Interoperability Group" has been working on standard 
conventions for representing 
unstructured grids in netCDF, for applications such as ocean models, although 
that may be limited
so far to netCDF-3 representations.  You can find out some of the work of 
members in this group here:

  https://groups.google.com/forum/?fromgroups#!forum/ugrid-interoperability

I know there has been some work on netCDF representation and visualization of 
LIDAR point-cloud 
data, but I don't know much about it.  UNAVCO was looking into this 
(specifically Jeff McWhirter), and
they may have settled on an RDB representation instead of netCDF, but I haven't 
been following that.
Unidata's IDV software can visualize point-cloud data, but I'm not sure if it 
depends on conventions for
netCDF representation, but you might ask address@hidden.

I think it would be pretty easy to represent a shape file using netCDF-4, with 
variable-length and
compound user-defined types in a nested varlen of compounds.  There was an HDF5 
paper a few
years back that showed an implementation of shapefiles using those types:

  http://www.hdfgroup.org/projects/nara/Sci_fmts_and_geodata_HDF.pdf

I'm not sure about geotiff, but GDAL software may provide a way of mapping a 
geotiff into a netCDF
representation ...

--Russ

> Thanks,
> -ohig
> 
> 
> 
> 
> 
> 
> -----Original Message-----
> From: Unidata netCDF Support [mailto:address@hidden]
> Sent: Sunday, June 09, 2013 8:36 PM
> To: Kwoun, Oh-Ig (398B)
> Cc: address@hidden
> Subject: [netCDF #CUE-552730]: GIS data
> 
> Hi Ohig,
> 
> > I have point cloud data that is intended for GIS application.  I want
> > to organize the point cloud data in 3D with a structure called R-Tree
> > which allows me a quick search in 3-D domain.
> >
> > http://en.wikipedia.org/wiki/R-tree
> >
> > Some one told me that I can use netCDF and another separate index file
> > to represent my point cloud data.  Does anyone know is there is a way
> > i can represent point cloud data iin one netCDF file?
> 
> That sounds like a possible approach, but we don't have any experience with 
> or software for using a netCDF representation of R-Tree data with a separate 
> index file.  Sorry we can't be of more help ...
> 
> --Russ
> 
> Russ Rew                                         UCAR Unidata Program
> address@hidden                      http://www.unidata.ucar.edu
> 
> 
> 
> Ticket Details
> ===================
> Ticket ID: CUE-552730
> Department: Support netCDF
> Priority: Normal
> Status: Closed
> 
> 
Russ Rew                                         UCAR Unidata Program
address@hidden                      http://www.unidata.ucar.edu



Ticket Details
===================
Ticket ID: CUE-552730
Department: Support netCDF
Priority: Normal
Status: Closed