Convert LIDAR data

Re: Convert LIDAR data

neilw — Thu, 13 Nov 2008 04:41:28 GMT

There seems to be a corrupt record in the data file that is preventing every application I've tried from editing the data. Civil 3D, MS Access, Context, Power Civil DTM Tools, etc. all have problems with the file so it looks like we will have to get it re-issued after all. Once we get a clean file I might try the Extract XYZ tool again and see what comes out. Once we get a proper xyz file we can use the LIDAR tools to filter it spatially and then thin the data if necessary.

Re: Convert LIDAR data

Robert Garrett — Thu, 13 Nov 2008 01:08:47 GMT

Extract XYZ should work but does not provide the filtering and thinning that you desire. You would end up with all umpteen gajillion points, when what you really want to do is thin the number of points to a managable size.

My experience with the LIDAR tools are limited so there might be a better way, but here is what I would do:

Make a copy of your LIDAR file
Open the copy in a text edotor that has ability to work column-wise, such as UltraEdit, which I use.
In column-wise mode I am able to highlight columns of data instead of lines and delete the extra columns of data.
Now use the copy sans the extra columns in the LIDAR tools.

Re: Convert LIDAR data

neilw — Wed, 12 Nov 2008 05:56:13 GMT

I tried those tools on a different data set and was not able to make it work. I'll look at them again when I get a chance but for now I have put out a call for a revised dataset from the provider. Meanwhile Mike Barkasi offered to edit the file for me so it will be interesting to see what he can do.

Re: Convert LIDAR data

IanTidy — Wed, 12 Nov 2008 05:46:47 GMT

Have you tried using the 'Extract XYZ' Tool (From the DTM Toolbar)? This is a bit slower than the 'DTM LiDAR Routines' but allows you to specifiy the columns in your XYZ file.

Hope this helps. :)

Cheers Ian