LAS Dataset to Raster Error

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11
08-03-2015 08:47 AM
by Anonymous User
Not applicable

Good Morning Everyone,

I am currently having an error while taking a LAS Dataset file and created a Raster. My end goal is to use the Raster for 1 foot contours for a current map I am creating for my Environmental team. As I ran the geoprocessing tool on ArcGIS, the error states, "Error 999999: Error executing function." With the more detailed error session stating, "The specified file or folder does not exist". If you anyone has an idea what might be going wrong with the process, I would love to figure it out and learn something new.

Overall goal: To create a map with 1 foot contours at 1:3000 scale. Buildings to be excluded and ground elevation the only desired attribute/feature class. If there is anything else I should explain, let me know. Thanks.

Very Respectfully,

Zachary J. Roy

11 Replies
IanMurray
Frequent Contributor

Can you post a screenshot of the parameters you used and the geoprocessing results(Inputs, Messages)?  What Raster Type are you saving out, what type of workspace(directory, fGDB)?  Alot of times 999999 errors can be the result of the filepath of the saved file being too long or the file name being too long depending on the raster type(i.e. ESRI grids can only be 11 characters).

For making grounds contours from LAS Datasets, you should make sure you LAS Dataset is only using points classified as ground before converting to raster.  

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by Anonymous User
Not applicable

LAS_Dataset_Error.jpg

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by Anonymous User
Not applicable

Thanks for the reply Ian. I'm currently trying to save it into a file geodatabase, and all of the parameters are default for the actual geoprocessing tool. Before converting the lasd file to raster, I classified it only for ground. When loading the file into the tool. I still receive the same message. Thanks again Ian. Sounds like you have seen this before.

-Zach

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IanMurray
Frequent Contributor

Is the las files that you are using for the LAS Dataset on a network drive?  The file path you are using for it has alot of extra periods in it which could be causing ArcGIS to have problems handling it for the tool.  Can you try to save the las files on a local drive and make sure the file path has no extra special characters or spaces in it, these can easily trip up ArcGIS geoprocessing tools.  Then have the LAS Dataset use the local copy las files and see if it still is having an issue.

Also I would recommend possibly changing some of the parameters for the tool.  For example the sampling type defaults to cellsize which is fine, but you have the option to change the sampling value below that to determine the output raster cell size.  When I bring up the tool it defaults to 10, which if my dataframe is in meters means I will have 10mx10m  pixels(even in feet this would be 10ft by 10ft).  Those are far too large for generating accurate 1ft contours like you are wanting.  Do you know the average point space of the las files that you received?  I would highly recommend reading the tool help and understanding the parameters you better than just going with the defaults.

by Anonymous User
Not applicable

We are getting somewhere Ian. How could I find the point spacing of the lasd file? I currently saved it to a local drive and changed the name, minus the special characters as you mentioned. Once I figure the point spacing, I will mess with parameters and see if the processing works, and it accurate. Look forward to your reply.

-Zach

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XanderBakker
Esri Esteemed Contributor

If you have resolved the network access to the underlying LAS file (that's definitely what is going with the LAS dataset):

... then you could use the 3D Analyst tool (if you have access to 3D Analyst) that converts a surface (including LAS dataset) to contours: Surface Contour—Help | ArcGIS for Desktop

No need to convert to raster first...

IanMurray
Frequent Contributor

Thats a good suggestion, though I am worried about the significant negative values that the LAS Dataset contains, converting to a raster then removing negative values might be helpful(unless the negative values are truly below sea level and not an artifact of errors in the las files). 

XanderBakker
Esri Esteemed Contributor

Yeah, I noticed these too and it seems that erroneous points have not been filtered (correctly). May have to contact the provider to see why these haven't been filtered.

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IanMurray
Frequent Contributor

Whoever is the source of your lidar data should be able to tell you the average point spacing(They would have received it from the vendor who flew and processed the LiDAR).  If you can't get in touch with the source, you could download LAStools and use the LASINFO tool to get the metadata from the las files which also could tell you.

The download is free, but there is a licensing cost, and without the license any operations performed on the data would have intentional errors(to make people get the license).  That said it should allow you to use the LASINFO tool and not perform errors since its not performing any spatial operations, just checking the metadata.

LAStools: converting, filtering, viewing, processing, and compressing LIDAR data in LAS format

I'm assuming that if the lidar data has been collected in the last few years it would be an average point spacing of ~1m or better which would translate decently into about a 1m resolution DEM.  I would recommend getting the tool working correctly first, then worry about the average point spacing and DEM resolution you will want to work with.

In case you need a reference for average point spacing(or nominal point spacing).  See  this USGS publication.  They talk about the LiDAR quality levels based on point spacing and what is the minimum dem resolution they get from vendors based on the quality level of the lidar(or nominal point spacing)(see pages 5 and 15 respectively).

http://pubs.usgs.gov/tm/11b4/pdf/tm11-B4.pdf