topic Re: Toruble with LiDAR data and using the tool Mosaic To New Raster with multiple images in Data Management Questions

Toruble with LiDAR data and using the tool Mosaic To New Raster with multiple images

StevenNacinovich — Tue, 02 May 2017 18:53:45 GMT

I'm having trouble running the tool Mosaic To New Raster with multiple LiDAR datasets. I have around 30-40 image datasets and I want combine them into one raster image that I can then use for watershed mapping. For some reason when I run the tool, it either won't show the rasters or only a handful of the input rasters show up, not the whole. I've already tried zooming to raster extent in TOC but that didn't help.

Set my Processing Extent parameters in environments to: Union of Inputs

Output location is in a file geodatabase

Have tried pixel types: 8_BIT_UNSIGNED & 32_BIT_FLOAT. neither with any success

I'm fairly new to LiDAR data in ArGIS so this may be a simple issue but I've been having trouble figuring it out. Any help on the matter would be much appreciated.

-Steve N.

Re: Toruble with LiDAR data and using the tool Mosaic To New Raster with multiple images

JakeSkinner — Tue, 02 May 2017 19:21:16 GMT

Hi Steven,

I would recommend adding your LiDAR data to a mosaic dataset:

Adding lidar data to a mosaic dataset—Help | ArcGIS Desktop

Re: Toruble with LiDAR data and using the tool Mosaic To New Raster with multiple images

IanMurray — Tue, 02 May 2017 19:21:31 GMT

Hi Steven,

Your nomenclature is a little off and I want to make sure its understood what the issue is. You say you have multiple "LiDAR Datasets", but LiDAR data is not a raster format, rather a point cloud usually in the form of a .las or .laz. I'm guessing what you are working with are raster Digital Elevation Models, Intensity Images, or something similar raster file that is generated from the LiDAR point cloud, not the "LiDAR Datasets" themselves.

According to this stackexchange thread, sometimes ArcMap cannot render all of a raster image at its full extent and zooming into a smaller than full extent would fix the issue(so the tool works correctly, but display incorrectly). It also has suggestions for working around to build a mosaic in a more manual fashion. You could run cell statistics or something similar on your output to make sure there are not a large number of no data cells that would be indicative that the tool ran incorrectly.

It would be helpful to know what file format your raster data is currently in, as well as what the export file type you are trying to create. Also have you tried to create the output to just a regular folder instead of a FGDB to see if that changes results?

Hope this helps,

Ian

Re: Toruble with LiDAR data and using the tool Mosaic To New Raster with multiple images

StevenNacinovich — Tue, 02 May 2017 19:26:45 GMT

I apologize. I'm working with 1meter DEM files that were obtained from LiDAR point cloud

Re: Toruble with LiDAR data and using the tool Mosaic To New Raster with multiple images

StevenNacinovich — Tue, 02 May 2017 19:39:16 GMT

It worked! Instead of saving it to a FGDB I just saved it in a regular old folder and the rasters were combined to one image. Thanks for the help,

Steve N,