writing projection information to las file NOT las dataset

[norrislam]

Hello,

I am trying to write in the projection information to my .las files (I know the projection but they are not written in the original .las files). I was able to add the .las files to a las dataset and set the projection in the las dataset. Now I would like to have that written permanently to the las files (in the header) but I can't seem to find the right tool.

I am looking at the the ArcGIS 10.1 help manual and it says that it is possible to 'Rewrite the LAS files to contain the proper spatial reference information. There is a sample tool available in the gallery on the 3D GIS resource center to automate this process.'

But when i click on the provided link (3D GIS resource center) I get the main page. I also tried to search for the tool at the 3D GIS center and I didnt get anything.

Any ideas?

thanks.
Nola

[TarunJaiswal]

Greetings Nola!

I believe what you are looking for is LAS Dataset Tools. Please check the Define LAS Projection tool under this tool box.

Hope this helps.

[norrislam]

Hi Tarun,

Thanks for the link, these are good tools to have!

But I was wondering if there is a way to actually rewrite the .las file with the new projection information.

According to the ArcGIS help, 'Rewrite the LAS files to contain the proper spatial reference information.' so I am thinking it is possible to have the spatial information written into the .las file.

I am using the las file in different software packages and it would be great to have the spatial info in the las files.

[EricRice]

Nola,

The LAS specification requires that spatial reference information always  be included in the header information of all LAS files.  ArcGIS will  read and use the spatial reference information if one exists in the LAS files.  We know that not every producer of LAS follows the specification so there are tools to fix the header.  The link Tarun  provided is useful, but I think you are looking for the LAS to LAS tools which allow you to add or fix the projection information stamped into the LAS header.

Best Regards,
Eric