topic Re: ASCII (XYZ) to LAS in 3D Questions

ASCII (XYZ) to LAS

KlausB__Vestergaard — Thu, 11 Aug 2011 08:40:56 GMT

Thank you for implementing LAS Dataset and the new toolbar.

Since the new tools only supports LAS files, I need a tool to convert ASCII to LAS, so large ascii files containing xyz can be handled in a efficiant manner?

When I Google "ASCII to LAS" I get some very interesting hits, but I'm unsure where to start ....

Re: ASCII (XYZ) to LAS

ClaytonCrawford — Wed, 17 Aug 2011 16:21:46 GMT

Do you have return numbers, class codes, intensity values, etc., that you need access to? What do you intend to do with your lidar data? Going to LAS may not be your best option.

Re: ASCII (XYZ) to LAS

KlausB__Vestergaard — Thu, 18 Aug 2011 10:12:45 GMT

The ambition is to work with 100's of millions of xyz registrations from bathymetric dataset currently stored as .asc files.

Both QA/QC and the ability to rapidly build terrains, extracting profiles, 3d visualization etc. is of interest.

I'm told that there's additional attributes in the files, origin from the raw scan data, that are similar to those from airborne Lidar.

Is there any other way to handle very large xyz (100 -1.000 mio points) as effectivly as the LAS Dataset?

K

Re: ASCII (XYZ) to LAS

KlausB__Vestergaard — Fri, 19 Aug 2011 07:08:08 GMT

Do you have return numbers, class codes, intensity values, etc., that you need access to? What do you intend to do with your lidar data? Going to LAS may not be your best option.

Hi Clayton!

Can Esri provide a LAS sample dataset complete with RGB, Intensity, Class etc.?

The Harrison.las from the "Working with 3D Analyst" class has no RGB, and only contains Ground Points, so it makes it difficult to test the new filtering options in the LAS Dataset Toolbar.

Brgds,

Klaus

Re: ASCII (XYZ) to LAS

XanderBakker — Fri, 26 Aug 2011 11:41:15 GMT

There are several websites that provide LAS files. I have tested ArcScene 10.1 beta with some of the LAS files located at http://liblas.org/samples/.

LAS file "2398_400.las" contains RGB values.

Alternatively, you could use software to convert your text files to LAS. I have installed LP360 (30 day evaluation) and it can convert text files (like PTS) to LAS. Make sure to choose LAS version 1.2 in LP360 to enable RGB.

Good luck!

Re: ASCII (XYZ) to LAS

ClaytonCrawford — Tue, 06 Sep 2011 22:32:11 GMT

You might try the txt2las utility from LasTools: http://www.cs.unc.edu/~isenburg/lastools/

Re: ASCII (XYZ) to LAS

XanderBakker — Wed, 07 Sep 2011 05:51:21 GMT

You might try the txt2las utility from LasTools: http://www.cs.unc.edu/~isenburg/lastools/

Indeed Clayton is right, the LAS tools by Martin Isenburg are a great resource for converting ASCII files to LAS (and for a lot more). It would be nice though if Esri would get in touch with Martin Isenburg and include some of this functionality in ArcGIS, in order to avoid the command line usage.

BTW I used the command below to convert a PTS file to LAS which was successfully converted to LAS dataset and visualized in ArcScene:

txt2las -i Vopak023col.txt -parse xyzsRGB -skip 1 -o vopak023col.las -set_version 1.2

I wasn't able to import the intensity (4th column) since the value is out of range...

Re: ASCII (XYZ) to LAS

LucienDavids — Sun, 16 Oct 2011 12:45:11 GMT

There are several websites that provide LAS files. I have tested ArcScene 10.1 beta with some of the LAS files located at http://liblas.org/samples/.

LAS file "2398_400.las" contains RGB values.

Alternatively, you could use software to convert your text files to LAS. I have installed LP360 (30 day evaluation) and it can convert text files (like PTS) to LAS. Make sure to choose LAS version 1.2 in LP360 to enable RGB.

Good luck!

Hi Xander,

I downloaded the file to experiment with. I seem to be unable to load *.las (v1.2) in ArcScene (and toolboxes). Could you tell me how to do this?

Thanks in advance.

regards Luc

Re: ASCII (XYZ) to LAS

XanderBakker — Mon, 17 Oct 2011 07:24:14 GMT

I downloaded the file to experiment with. I seem to be unable to load *.las (v1.2) in ArcScene (and toolboxes). Could you tell me how to do this?

Hi Luc,

You have to create a LAS dataset with the new "Create LAS Dataset" tool. You'll find this in 3D Analyst Tools / Data Management / LAS Dataset (or just do a search for "LAS Dataset"). You are not able to add LAS files to ArcMap or ArcScene directly, but after you create the LAS Dataset you're good to go.

You may also be interested in this Esri video where native support for Lidar is explained by Nathan Shephard:

http://video.esri.com/watch/454/native-support-for-lidar

Good luck!

Kind regards,

Re: ASCII (XYZ) to LAS

LucienDavids — Sun, 13 Nov 2011 13:20:42 GMT

Hi Luc,

You have to create a LAS dataset with the new "Create LAS Dataset" tool. You'll find this in 3D Analyst Tools / Data Management / LAS Dataset (or just do a search for "LAS Dataset"). You are not able to add LAS files to ArcMap or ArcScene directly, but after you create the LAS Dataset you're good to go.

You may also be interested in this Esri video where native support for Lidar is explained by Nathan Shephard:

http://video.esri.com/watch/454/native-support-for-lidar

Good luck!

Kind regards,

Hi Xander,

Thanks for the reply. I found out how to deal with it with some help from esrinl how to create the LASD. Now I am going to watch the video :).

regards

Luc

Re: ASCII (XYZ) to LAS

KlausB__Vestergaard — Mon, 02 Jan 2012 13:42:17 GMT

Hi Clayton!

I've submitted an enhancement request on NIM076439 "Need a tool to convert xyz point data to LAS format."

I also posted my idea "Ability to convert xyz point data to LAS format" on:
[https://c.na1.visual.force.com/apex/ideaView?id=08730000000bt5qAAA[/URL]

The matter has become more urgent the last few months, so is there anything you can do to push on the inside of Esri?

Do you have return numbers, class codes, intensity values, etc., that you need access to? What do you intend to do with your lidar data? Going to LAS may not be your best option.

Re: ASCII (XYZ) to LAS

KlausB__Vestergaard — Mon, 02 Jan 2012 13:50:39 GMT

Hi Xander!

Thanks for your reply, meanwhile I've submitted an enhancement request on NIM076439 "Need a tool to convert xyz point data to LAS format."

I also posted my idea "Ability to convert xyz point data to LAS format" on:
[https://c.na1.visual.force.com/apex/ideaView?id=08730000000bt5qAAA[/URL]

Please cast your vote ;o)

I really think that implementing "LAS Dataset" in 10.1 needs to be complimented with a easy to use conversion tool.

There are several websites that provide LAS files. I have tested ArcScene 10.1 beta with some of the LAS files located at http://liblas.org/samples/.

LAS file "2398_400.las" contains RGB values.

Alternatively, you could use software to convert your text files to LAS. I have installed LP360 (30 day evaluation) and it can convert text files (like PTS) to LAS. Make sure to choose LAS version 1.2 in LP360 to enable RGB.

Good luck!

Re: ASCII (XYZ) to LAS

AntonLarsson — Mon, 10 Apr 2017 16:47:35 GMT

I got LiDAR-data from a guy that said it was ascii. file-format says .cenz. Anybody heard of .cenz? when i open the file in texteditor: Class x y z

How can i make a pointcloud out of this?

regards,

Anton

Re: ASCII (XYZ) to LAS

XanderBakker — Tue, 11 Apr 2017 13:42:24 GMT

The suggestions mentioned above (using LAStools to convert the ASCII data to LAS) are still valid. Have you tried that?

Re: ASCII (XYZ) to LAS

NeilAyres — Tue, 11 Apr 2017 14:01:33 GMT

And if you download LasTools these days, it comes with a bunch of Arc style Toolbox tools.

Very good tool set.

Re: ASCII (XYZ) to LAS

AntonLarsson — Thu, 13 Apr 2017 10:30:49 GMT

If i try txt2las it says invalid filetype. I manage to make shape-points of it by adding the data into excel and then export as csv and the create points from XY. Then i tried to run shp2las but always when i try to use LasTools i get error. Could that be a licence issue?

/ Anton

Re: ASCII (XYZ) to LAS

NeilAyres — Thu, 13 Apr 2017 10:41:51 GMT

The toolset is free as far as i know.

Are the files still names *.cenz?

Try changing the extension to txt

Re: ASCII (XYZ) to LAS

AntonLarsson — Thu, 13 Apr 2017 12:33:24 GMT

I did try and still got error using txt2las. I will redownload LasTools and try again. I did also try using FME xyz point cloud -> LAS did go through but nothing showing.

Re: ASCII (XYZ) to LAS

AntonLarsson — Thu, 13 Apr 2017 12:44:06 GMT

It´s also very big amounts of data so i did try everything with just a few points. Didn´t work.

Re: ASCII (XYZ) to LAS

AntonLarsson — Sun, 23 Apr 2017 20:27:38 GMT

I did try the new update of LasTools and i didn't work. As you can see above i have 4 columns: Class x y z. Could that be the problem? when i try FME the program only reads the first 3 columns and it doesn't work. I have lots of rows so it's not possible to import in excel an delete the first column either. Any ideas what i could try next? I have also tried to make a shapefile with points and then transform to LAS in FME, didn't work. In txt2Las i tried to change the phrase string to cxyz, c=classification.

The files i got was in an unknown format to me, .cenz. How did you mean i should make it a .txt instead? I did copy the data in to a txt-file. Maybe that's a problem?

Thanks for your time,

Anton