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I am attempting to replicate the process of creating digital elevation models from raw LiDAR data and have been provided with LAS files covering an approximate 530 square mile county area. However, I only need to work with about 1/4th of this coverage, which is still at least 30+ las files.

What is the most efficient way to identify the files that are located within the boundary of my AOI (area of interest)?

The company that delivered the LiDAR data did include an ArcMap map document that contains a point cloud LAS dataset file but I'm not sure how/if I can manipulate that along with my boundary polygon.

  • What workflow are you attempting to replicate? Are the DEMs already created? – Barbarossa Aug 6 '15 at 15:27
  • @Barbarossa I am attempting to replicate the process of creating DEM's that are derived from LiDAR data. The company did provide DEM's for my area, however, I wanted to get hands on practice with the LiDAR data myself for familiarity. – Tobel Aug 6 '15 at 16:35
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    Clipping from ArcGIS LAS dataset is possible. You'd need the LAStools Production toolset (it is not free tough). Duplicate: gis.stackexchange.com/questions/122496/… – Andre Silva Aug 7 '15 at 16:50
  • Linking related question: Tracking which LiDAR data tiles have been delivered – Andre Silva Dec 7 '15 at 16:35
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A LAS dataset is probably the way to go. The ESRI help file is useful, so I recommend you starting there. For example:

The list below includes common examples of how to benefit from using LAS datasets to initially incorporate lidar data in GIS. With LAS datasets you can:
...
+ Conduct initial QA\QC, such as assessing data coverage and point sample density, for newly acquired lidar data.
....
+ Incorporate additional breaklines or surface features with lidar.

They provide a pretty nice way of looking at large coverages of lidar data. I would start off with loading all your LAS files into a dataset and then using that to identify which individual LAS files you really need - then making a second dataset using only those files (so that it will be as small as possible and less cumbersome).

This of course assumes you have access to a version of ArcGIS that can handle LAS datasets, which I believe means 10.1 and later. Here you find more info about the DEM part in your workflow.

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Try using LAS Tools which is a toolbox that can be downloaded for free. This is what I use for nearly all of my LiDAR data, and it is very user friendly. From here you can use tools that will allow you to filter, convert, and refine your raw .las point cloud data into a LAS dataset and from the dataset to a DEM. Here is a video on youtube that will show you how to convert the .las to a raster (DEM).

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    Specifically, if you want to clip data to a boundary polygon, take a look at lasclip. – Barbarossa Aug 6 '15 at 15:23
  • Thank you for the LAS Tools link and @Barbarossa for pointing out lasclip, that is exactly what I was looking for. And also to Kevin as that is an excellent resource on what I can do with the LiDAR data. – Tobel Aug 6 '15 at 17:51
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    The lasclip tool only seems to accep a single LAS file. I will keep digging to see if there is a tool that will accept the entirety of the LAS dataset for input to be clipped – Tobel Aug 6 '15 at 18:01

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