[pgpointcloud] [EXTERNAL] Chipping LIDAR FROM OpenGeo

[Howard Butler]

On Jul 9, 2014, at 8:47 AM, Smith, Michael ERDC-CRREL-NH <Michael.Smith at usace.army.mil> wrote:

> Dean,
> 
> You don't need to chip it to export. You'd add a crop filter with a WKT geometry and write that direct to your output format.

Correct, but you want to limit the amount of data you fetch beforehand. Use a where clause on the drivers.pgpointcloud.reader to fetch only what you might need first. See http://www.pdal.io/stages/drivers.pgpointcloud.reader.html for more details.


On Jul 9, 2014, at 8:41 AM, <Dean.Hand.ctr at nga.mil> <Dean.Hand.ctr at nga.mil> wrote:
> 
> PDAL is a great tool.  It allows us to chip, mosaic, and parsing LIDAR files into OpenGeo.

I think you mean chip and load into pgpointcloud or PostgreSQL.

> 
> Has anyone worked on creating the ability to chip LIDAR from OpenGeo and export it out as a las/laz/or xyz file.  For example, there's a rather large LIDAR table in OpenGeo and you only want a small area to exploit in QT Modeler.  How would one go about chipping that area and exporting it?

After you've loaded into pgpointcloud, fetch it back out again. See http://www.pdal.io/stages/drivers.pgpointcloud.reader.html for an example that writes text. It should be straightforward to adapt it to use the drivers.las.writer instead.

Howard