Questions tagged [lidr]
R package for Airborne LiDAR Data Manipulation and Visualization in Forestry Applications
337 questions
0 votes
1 answer
26 views
Bug in lidR when identifying tree canopy surfaces in LAScatalog?
I am trying to identify tree canopy surfaces using lidR in an urban area. To do this, I have been trying to use the readLAScatalog() functionality to prevent memory issues. If I use my code on a ...
- 71
0 votes
1 answer
66 views
Addressing inconsistent offsets and overlapping in LiDAR data using lidR
I'm a novice to LiDAR who's currently attempting to rasterize groups of point cloud tiles (downloaded from the USGS) into DTMs using lidR. When I load a group of tiles into a LAScatalog and run ...
1 vote
0 answers
59 views
Providing bounding box for lidR to find trees
I have a laz file and working with lidR for tree detection and segmentation. So far, My workflow is like this: import and clip laz file (already has ground points classified) las12_mot <- ...
2 votes
1 answer
58 views
Gap between tiles from lidR LAScatalog
I am processing LiDAR tiles using a LAScatalog from the lidR package in R. When I specify a raster template for the res argument in pixel_metrics, there is a one-pixel gap between the raster tile ...
- 928
0 votes
0 answers
61 views
Using LidR to add new attribute to LAS file point cloud from GeoTIFF raster
I am currently trying to add a new attribute to a LAS file so I can use it for classification of the points, based on the values in a GeoTIFF file. For this I am using the merge_spatial function in ...
- 11
1 vote
0 answers
63 views
How do I move a point cloud from lasR to lidR package most efficiently?
Starting from a set of LAZ files, I want to use the lasR package to create a DTM and a normalized point cloud. Then I want to move my data to the lidR package for some more technical processing. What ...
- 137
1 vote
1 answer
47 views
lidR does not update header when both VLR and EVLR supplied
I am using lidR version 4.1.2 and some of my files have projections written in both the VLR and EVLR fields. However, when I use st_crs(some_laz) = "some_crs" only the VLR is being updated ...
- 171
2 votes
1 answer
129 views
Calculate LiDAR metrics for "first and single" returns and "last and single" returns
I have been using lidR to calculate metrics for different classes of echo using the argument by_echo. With this argument "the metrics are computed multiple times for different echo types. Can be ...
- 401
0 votes
0 answers
85 views
Correcting GPS time incoherances in a LAS file
I am Working in R using the lidr package to do tree canopy delination. When I am checking my LAS file I receive the following messages: Warning: There are 11063 points flagged 'withheld'. Checking the ...
0 votes
0 answers
67 views
lidR raster creation crashing with feet projection system
I'm trying to debug an issue while processing LiDAR data in R using the lidR package (R: 4.4.0, lidR: 4.1.1). I'm trying to convert voxels to rasters with a user-defined function. I have run this ...
2 votes
1 answer
116 views
DTM and DSM from the same LAZ file - extent do not match
I'm trying to extract tree tops, and I have successfully processed dozens of LAZ files with R, but I have a problem with one. als_dir <- "C:/Users/bzzzzzzi/Documents/dummy/KRON86/09/" als ...
0 votes
1 answer
111 views
Systematically clip a large point cloud file into smaller ones for further processing
I have a large .las point cloud file that I want to process using the lidR package in R. Since the file is too large to process at once, and R eventually crashes, I have to clip/subset my file into ...
- 3
0 votes
1 answer
145 views
Why are there "no returns" in my point cloud and am not able to display or process it in lidR?
I have a point cloud I collected and converted to a .las in the proprietary software "FARO Connect". I am able to visualize the point cloud in the software. However, when taking the .las ...
- 23
0 votes
0 answers
49 views
Proportion of LiDAR point coverage is required to form a 30-m pixel while calculating pixel metrics
I am calculating pixel metrics (30-meter resolution) at area level with the ALS data using lidR package in R. Since the study area has irregular shape, I could see that pixels were formed in some ...
- 1
1 vote
1 answer
227 views
Why does readLAS() not work in older versions of lidR anymore?
I am unfortunately dependent on an older version (4.0.4) of the lidR package due to a package dependency. Strangely enough, the import of LAS files with readLAS() no longer works since a system update....
- 13