Generally (raw) LIDAR data is not on a regular grid, it's irregular. So it's not a raster problem it's a billions-of-points problem, and not just a billions-of-points problem, but a billions-of-hyper-dimensional-points problem (though the indexing can be in just 2- or 3-d, really). So grid-based solutions aren't really going to do it.
P. On Thu, Jul 8, 2010 at 9:22 AM, Paragon Corporation <[email protected]> wrote: > Okay since everyone is providing their suggestions, let me provide my less > than educated suggestion based on my fuzzy assumption of how Lidar is > structured. > > Why don't you just use the new WKT Raster (PostGIS raster storage)? It > allows you to store multiple bands per pixel. I think you might even be > able to use GDAL to load the Lidar data right in ot the PostGIS raster > storage format given this bug fix. > > http://trac.osgeo.org/gdal/ticket/3523 > > So I'm imaging your z, range, target number, reflectance you would store as > separate raster bands. > > Pierre and Jorge can correct me, but I don't think there is a limit on the > number of raster bands you can store per raster tile > > http://www.postgis.org/documentation/manual-svn/RT_reference.html > > With that you can do spatial intersects queries to pull out the different > band values with > > http://www.postgis.org/documentation/manual-svn/RT_ST_Intersection.html > > or > > http://www.postgis.org/documentation/manual-svn/RT_ST_Value.html > > The meta data function would be useful for letting you know how many bands > you have etc. > > http://www.postgis.org/documentation/manual-svn/RT_ST_MetaData.html > > Hope that helps, > Regina > ________________________________ > From: [email protected] > [mailto:[email protected]] On Behalf Of Peter > Baumann > Sent: Thursday, July 08, 2010 9:32 AM > To: PostGIS Users Discussion > Subject: Re: [postgis-users] lidar: what is the recommended wayof > storing/indexing > > Indeed, a column store for arrays is usually quite ;-) inefficient. > Let me point you to the rasdaman array DBMS which plugs into PostgreSQL and > offers an optimized array query language on top. See www.rasdaman.org. > > -Peter > > > > > Paul Ramsey wrote: > > Oh, actually one-row-per-point is a bad idea, because the size of > lidar sets mitigates against that. Putting them into multipoint > collections of 50 or 100 points is better. But that implies > preprocessing things a bit to find good patches. In generally, there's > a lot of tooling needed to do this well, I fear. > > P > > On Thu, Jul 8, 2010 at 6:27 AM, Paul Ramsey <[email protected]> wrote: > > > There is no recommended way right now. It's a core development > activity I'd love to have funded... :) > > http://opengeo.org/products/coredevelopment/postgis/pointclouds/ > > In the meanwhile a approach might be to put the x/y/z into a postgis > geometry and stuff the rest of the data into an array of doubles in > another column. Your app would need to know which array element was > which kind of data, but you'd still have it all available. > > P. > > On Thu, Jul 8, 2010 at 2:53 AM, Biddy <[email protected]> wrote: > > > Hi everyone, > > is there a recommended way of storing lidar data in postgis? > > In particular, I am interested in not just storing long, lat, alt but also > keeping all the raw data (for example range, target number, reflectance, > etc.) > > Regards, > B. > > > _______________________________________________ > postgis-users mailing list > [email protected] > http://postgis.refractions.net/mailman/listinfo/postgis-users > > > > _______________________________________________ > postgis-users mailing list > [email protected] > http://postgis.refractions.net/mailman/listinfo/postgis-users > > > -- > Dr. Peter Baumann > - Professor of Computer Science, Jacobs University Bremen > www.faculty.jacobs-university.de/pbaumann > mail: [email protected] > tel: +49-421-200-3178, fax: +49-421-200-493178 > - Executive Director, rasdaman GmbH Bremen (HRB 147737) > www.rasdaman.com, mail: [email protected] > tel: 0800-rasdaman, fax: 0800-rasdafax, mobile: +49-173-5837882 > "Si forte in alienas manus oberraverit hec peregrina epistola incertis > ventis dimissa, sed Deo commendata, precamur ut ei reddatur cui soli > destinata, nec preripiat quisquam non sibi parata." (mail disclaimer, AD > 10xx) > > > > _______________________________________________ > postgis-users mailing list > [email protected] > http://postgis.refractions.net/mailman/listinfo/postgis-users > > _______________________________________________ postgis-users mailing list [email protected] http://postgis.refractions.net/mailman/listinfo/postgis-users
