Coastal LiDAR: Difference between revisions

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This is called the "Coastal" LiDAR page because I generally go to NOAA's coastal data viewer to find my LiDAR.
Since I live near the coast it's generally the best place for me to go.
Currently I use the data for (1) my own education (2) TrailPeople projects.
For TrailPeople mostly I have been downloaded DEM's as a short cut for getting accurate elevation data.
I am trying to develop a good workflow for processing the LAS point data directly.
== Lincoln county, Oregon ==
Feb 2017-
I am looking for a house in Lincoln county and have decided to commit to a full GIS approach, so I am collecting all the data I can find to build up an analysis. Then I can look at properties from afar and be better informed.
Workflow: My intent is to go full open source on this project.
This will include LiDAR so that I can check on slope and aspect to help evaluate solar access. I want PV so I need sun.
== Santa Clara county ==
== Santa Clara county ==
2016-


For this project I want to closely examine a reach of road that goes into the hills to see if it can accommodate addition of a footpath.
For this project I want to closely examine a reach of road that goes into the hills to see if it can accommodate addition of a footpath.
Workflow: On this project I did use LAZ point files but I used ESRI tools.


I downloaded data that was collected by the Santa Clara Water District in 2006. The area of interest is small, covered by 4 tiles.
I downloaded data that was collected by the Santa Clara Water District in 2006. The area of interest is small, covered by 4 tiles.
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"This data set is an LAZ (compressed LAS) format file containing LIDAR point cloud data. LAS format files, raw LiDAR data in its native format, classified bare-earth LiDAR DEM  and photogrammetrically derived breaklines generated from LiDAR Intensity stereo-pairs.  Breakline, Top of Bank, and contour files in ESRI personal geodatabase format, Microstation V8 .dgn format, and AutoCAD 2004 formats for the San Jose Phase 3 project of Santa Clara County, Ca. This project arrived with only unclassified data. NOAAs Office for Coastal Management performed an automated classification using lasground.  Although class 1 and class 2 are available, there was no QA/QC on the points after lasground was performed."
"This data set is an LAZ (compressed LAS) format file containing LIDAR point cloud data. LAS format files, raw LiDAR data in its native format, classified bare-earth LiDAR DEM  and photogrammetrically derived breaklines generated from LiDAR Intensity stereo-pairs.  Breakline, Top of Bank, and contour files in ESRI personal geodatabase format, Microstation V8 .dgn format, and AutoCAD 2004 formats for the San Jose Phase 3 project of Santa Clara County, Ca. This project arrived with only unclassified data. NOAAs Office for Coastal Management performed an automated classification using lasground.  Although class 1 and class 2 are available, there was no QA/QC on the points after lasground was performed."


'''Generating surfaces from raw data''' For ArcGIS this means "terrains". For QGIS it means DEM rasters.
'''Generating surfaces from raw data''' For ArcGIS this means "terrains". For QGIS it means DEM rasters.
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http://www.laszip.org/
http://www.laszip.org/


== Gold Beach ==
== Gold Beach ==

Revision as of 17:53, 27 February 2017

This is called the "Coastal" LiDAR page because I generally go to NOAA's coastal data viewer to find my LiDAR. Since I live near the coast it's generally the best place for me to go.

Currently I use the data for (1) my own education (2) TrailPeople projects. For TrailPeople mostly I have been downloaded DEM's as a short cut for getting accurate elevation data. I am trying to develop a good workflow for processing the LAS point data directly.

Lincoln county, Oregon

Feb 2017- I am looking for a house in Lincoln county and have decided to commit to a full GIS approach, so I am collecting all the data I can find to build up an analysis. Then I can look at properties from afar and be better informed.

Workflow: My intent is to go full open source on this project.

This will include LiDAR so that I can check on slope and aspect to help evaluate solar access. I want PV so I need sun.

Santa Clara county

2016-

For this project I want to closely examine a reach of road that goes into the hills to see if it can accommodate addition of a footpath.

Workflow: On this project I did use LAZ point files but I used ESRI tools.

I downloaded data that was collected by the Santa Clara Water District in 2006. The area of interest is small, covered by 4 tiles. See https://coast.noaa.gov/htdata/lidar1_z/geoid12a/data/4870/ The data is in LAZ format.

What coordinate system is this data in? It's in WGS84 and the vertical unit is 1 meter.

First thing I want to do is generate simple first return and last return surfaces.

The files are already classified, see the metadata:

"This data set is an LAZ (compressed LAS) format file containing LIDAR point cloud data. LAS format files, raw LiDAR data in its native format, classified bare-earth LiDAR DEM and photogrammetrically derived breaklines generated from LiDAR Intensity stereo-pairs. Breakline, Top of Bank, and contour files in ESRI personal geodatabase format, Microstation V8 .dgn format, and AutoCAD 2004 formats for the San Jose Phase 3 project of Santa Clara County, Ca. This project arrived with only unclassified data. NOAAs Office for Coastal Management performed an automated classification using lasground. Although class 1 and class 2 are available, there was no QA/QC on the points after lasground was performed."

Generating surfaces from raw data For ArcGIS this means "terrains". For QGIS it means DEM rasters. I am starting with terrains, which means first I need to get the data out of the LAZ files and into ArcGIS.

http://www.spatialguru.com/lidar-data-to-raster-file-with-open-source-gdal-tool/

http://www.laszip.org/

Gold Beach

20-Apr-2011 Going to Gold Beach for Easter weekend, so naturally I am looking at Curry county data once again.

I have a nice NAIP 2009 photo of the area now. 1/2 meter 2009 county level files are available as zipped files via FTP from Oregon Explorer

Working with LiDAR obtained from the Oregon Coastal Atlas

Holes in LiDAR data

I have created a contour and a hillshade, which is great, but the LiDAR is full of holes! I think since it's a coastal dataset (NOAA) they don't care about the areas up a bit from the beach.

I am thinking I can fill the holes with 10m DEM data, so I found an example on how to do this and will look at it this evening.

http://blogs.esri.com/Support/blogs/mappingcenter/archive/2009/06/16/Filling-and-clipping-a-raster.aspx