Tips for Using LIDAR and LAStools in QGIS

LIDAR is an important technology that is undergoing continuous and expansive growth and predicted to reach $1 billion by 2020.  A recent report also describes ongoing developments in LIDAR in Europe. NOAA has a great one-hour Introduction to LIDAR that I recommend checking out: http://coast.noaa.gov/digitalcoast/training/intro-lidar

Source: Allied Market Research, https://www.alliedmarketresearch.com/lidar-market

LAStools is the popular LIDAR processing tool created by the developer of *.las and compressed *.laz formats.  There is a standalone program as well as toolboxes for a variety of programs including QGIS. We will cover a few tips and wrap up with a look at Wizard Island, Crater Lake, Oregon.

Linking LAStools with QGIS
Linking the two has gotten much simpler since QGIS 2.4.  Simply download the *.zip file from: http://lastools.org/download/lastools.zip.  Unzip the file, and copy and past the LAStools folder into a simple directory like "c:/" If you have QGIS running, close it before proceeding.

Tip #1: Users often copy the folder to a folder pathway that is complex and includes spaces like c:/Program Files/ or c:/My Documents. It will not work. Again, use simple path names, no spaces!

Tip #2: This also applies for any files you import with LAStools or export during processing in QGIS.

After doing this, start QGIS, go to the Processing Toolbar, click "Tools for LiDAR Data"->Activate-> and enter or browse to the folder pathway. I've been using LAStools with the most recent version of QGIS (2.10) and have not had any problems yet.

Linking LAStools and QGIS has gotten much easier!

Click "Ok", then head over to the Processing Toolbox side-panel, and you will see the tools ready-to-use!

Expand and see a wide range of tools at your disposal!
Note: The LAStools Production or PRO tools are for batch processing.

Tip #3: If you run a tool and nothing happens, be sure that NONE of the folder pathways, for importing data and exporting results, are complex and/or contain spaces.

Tip #4: Be sure to read the "Log" for important information and troubleshooting.

Tip #5:  When using lasview in QGIS, pressing Space bar changes your ability to navigate from zoom, tilt,pan, and translate.  In the upper-left of the window, you will see the navigation type change as you press it.

Furthermore, right-clicking the mouse, brings up a menu for changing the view of LIDAR, from selecting returns, how to symbolize/color data.

The right click menu in LAStools

Tip #6: To get a 3D view, press Space bar until Pan is displayed, if is not already.  Click and hold your mouse, then move it up to the top of the screen and voila!

Wizard Island, Crater Lake, Oregon, Data from: Open Topography. lasnoise was also used.

See also:
OpenTopography
Digital Coast
3D Elevation Program
Google search for "County lidar" and State LIDAR

Open Topography: A Well-Organized and Feature Rich Site

OpenTopography allows users to register, upload, and download high resolution topography data and tools. as well as download it.  It is run by two universities and funded through a National Science Foundation (NSF) grant.  Below is an overview video of the website.  It is important to note the social features at play and its goals of democratizing information sharing and discovery.



Finding LIDAR data is easy on OpenTopography.  Simply navigate on a map, click a point for more information on the data set, or zoom in for the full coverage area.  In addition, there is a list of tools available and links to them at:  http://opentopo.sdsc.edu/gridsphere/gridsphere?cid=tools.  Click on the screenshots below to take a closer look at using the site.  You can draw a bounding box to select an area of interest.

Finding data is a snap.  Currently, the overwhelming majority of the data is for the continental U.S.

While your data request is being processed, you will receive a nicely formatted report with the associated files and their descriptions. You will also receive an e-mail of the same report with links to your requested files.

Example of a Job Report for data for Washington DC.
Well Organized and Data Ready to Download!

Of course, not only is there free data but but also free tools, like LAStools in QGIS, for looking at your data from OpenTopography.

LIDAR data from OpenTopography visualized in LAStools.  Na Pali Coast, Kauai, Hawaii.
Points colored by elevation.  Pressing the space bar allows user to pan, zoom, rotate, etc. with the mouse.