[GRASS-user] Importing Point-Cloud with v.in.lidar

Wed Feb 12 08:30:31 PST 2020

Hello grass-community,

Actually I’m working for a research project (master thesis) with point  
data, that were exported from dronedeploy one year ago.
Unfortunately processing the exported LAS-files is quit challenging,  
as there are some issues with the file format (e.g. the projection).
My aim is to import the data into Grass-GIS to process it there with  
the 3D-fragmentation tool. But till now I was not able to import it…  
So I thought I’ll ask for some help here.

I tried to process the data with several tools, like lidR package in  
R-Studio and LAStools. First I had to change the projection with  
las2las to a appropriate (EPSG 3116) one, to be able to display it  
correctly in these tools. Now I can do further processing with the  
data, like creating grids. By the way, these grids are located  
correctly when loading them to a GIS-application. So coordinates seem  
to be correctly. Anyway loading the point-data to Grass-GIS (with  
v.in.lidar tool) fails, because the points are in a wrong  
location/projection. I did not use -r (limit to current region), so  
this can not be the problem. First it did calculate something and  
added a vector map that seemed to be empty, because there was nothing  
displayed.
Actually it doesn’t even start calculating and there is no vector map  
produced. I copied the output below. I already got the hint to try  
importing a ASCII text by converting the LAS file with PDAL. So I will  
try installing PDAL on my PC. Anyway, maybe some has a solution for  
the v.in.lidar problem.

Output:
QGIS version: 3.10.2-A Coruña
QGIS code revision: d4cd3cfe5a
Qt version: 5.11.2
GDAL version: 3.0.4
GEOS version: 3.8.0-CAPI-1.13.1
PROJ version: Rel. 6.3.0, January 1st, 2020
Processing algorithm…
Algorithm 'v.in.lidar' starting…
Input parameters:
{ '-b' : False, '-c' : False, '-t' : False,  
'GRASS_OUTPUT_TYPE_PARAMETER' : 0, 'GRASS_REGION_PARAMETER' :  
'1209933.8649246846,1210526.7738715957,820900.5310786865,821470.5180333158  
[EPSG:3116]', 'GRASS_VECTOR_DSCO' : '', 'GRASS_VECTOR_EXPORT_NOCAT' :  
True, 'GRASS_VECTOR_LCO' : '', 'class_filter' : '', 'input' :  
'C:\\Users\\oc\\OneDrive - HH  
Gruppe\\Dokumente\\Uni\\Master\\Daten\\Daten_Stuktur\\points\\110_1.las',  
'limit' : None, 'offset' : None, 'output' : 'TEMPORARY_OUTPUT',  
'preserve' : None, 'return_filter' : [], 'skip' : None, 'spatial' :  
None, 'zrange' : [nan,nan] }

g.proj -c proj4="+proj=tmerc +lat_0=4.59620041666667  
+lon_0=-74.0775079166667 +k=1 +x_0=1000000 +y_0=1000000 +ellps=GRS80  
+towgs84=0,0,0,0,0,0,0 +units=m +no_defs"
g.region n=821470.5180333158 s=820900.5310786865 e=1210526.7738715957  
w=1209933.8649246846
v.in.lidar -o input="C:\Users\oc\OneDrive - HH  
Gruppe\Dokumente\Uni\Master\Daten\Daten_Stuktur\points\110_1.las"  
output=output2221d86f3dd44a7c84ead4bac980f243 --overwrite
v.out.ogr type="auto" input="output2221d86f3dd44a7c84ead4bac980f243"  
output="C:\Users\oc\AppData\Local\Temp\processing_073544cf878b4dd8b5311a6a5d27abcc\cc8523d5d751483b9922084e16845571\output.gpkg" format="GPKG" -c  
--overwrite
Starting GRASS GIS...
WARNING: Concurrent mapset locking is not supported on Windows
Cleaning up temporary files...
Executing  
<C:\Users\oc\AppData\Local\Temp\processing_073544cf878b4dd8b5311a6a5d27abcc\grassdata\grass_batch_job.cmd>  
...
C:\Users\oc\OneDrive - HH Gruppe\Dokumente>chcp 1252 1>NUL
C:\Users\oc\OneDrive - HH Gruppe\Dokumente>g.proj -c  
proj4="+proj=tmerc +lat_0=4.59620041666667 +lon_0=-74.0775079166667  
+k=1 +x_0=1000000 +y_0=1000000 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0  
+units=m +no_defs"
Default region was updated to the new projection, but if you have  
multiple mapsets `g.region -d` should be run in each to update the  
region from the default
Projection information updated
C:\Users\oc\OneDrive - HH Gruppe\Dokumente>g.region  
n=821470.5180333158 s=820900.5310786865 e=1210526.7738715957  
w=1209933.8649246846
C:\Users\oc\OneDrive - HH Gruppe\Dokumente>v.in.lidar -o  
input="C:\Users\oc\OneDrive - HH  
Gruppe\Dokumente\Uni\Master\Daten\Daten_Stuktur\points\110_1.las"  
output=output2221d86f3dd44a7c84ead4bac980f243 --overwrite
C:\Users\oc\OneDrive - HH Gruppe\Dokumente>v.out.ogr type="auto"  
input="output2221d86f3dd44a7c84ead4bac980f243"  
output="C:\Users\oc\AppData\Local\Temp\processing_073544cf878b4dd8b5311a6a5d27abcc\cc8523d5d751483b9922084e16845571\output.gpkg" format="GPKG" -c  
--overwrite
ERROR: Vector map <output2221d86f3dd44a7c84ead4bac980f243> not found
C:\Users\oc\OneDrive - HH Gruppe\Dokumente>exit
Execution of  
<C:\Users\oc\AppData\Local\Temp\processing_073544cf878b4dd8b5311a6a5d27abcc\grassdata\grass_batch_job.cmd>  
finished.
Cleaning up temporary files...
Drücken Sie eine beliebige Taste . . .
Execution completed in 13.86 seconds
Results:
{'output': <QgsProcessingOutputLayerDefinition  
{'sink':TEMPORARY_OUTPUT, 'createOptions': {'fileEncoding': 'System'}}>}

Loading resulting layers
The following layers were not correctly  
generated.<ul><li>C:\Users\oc\AppData\Local\Temp/processing_073544cf878b4dd8b5311a6a5d27abcc/cc8523d5d751483b9922084e16845571/output.gpkg</li></ul>You can check the 'Log Messages Panel' in QGIS main window to find more information about the execution of the  
algorithm.

Kind regards, Olivier Canon