error in segment_trees()

[taeyoonlee87]

Hello,

I tried to segment individual trees.

I created CHM using 'rasterize_canopy' and created the tree tops using 'locate_trees'.

I applied "st_as_sf" to convert tree tops to SF objects. Like below

opt_output_files(las_cat) <- ""
ttops <- locate_trees(las_cat, lmf(5), uniqueness = "bitmerge")
ttops2<- st_as_sf(ttops)

Then, I segment it using "segement_trees"

opt_output_files(las_cat) <- "/scratch/tl96575/mapping/chm/segmented_{XLEFT}_{YBOTTOM}"
algo <- silva2016(chm, ttops2)
ctg_segmented <- segment_trees(las_cat, algo)

but it resulted in the error message

#Chunk 1 of 635 (0.2%): state ✗
#Error: On-disk rasters not supported in 'raster_as_dataframe()'

When I test my code with a small portion of data, it worked without errors. But when I ran my code for the whole dataset, it gave me this error.

Did you ever see this error? Or could you please advise me on what point I need to check.?

[Jean-Romain]

Your code looks correct and should be handled automatically by segment_trees(). I will call it a bug.

#694

[taeyoonlee87]

Then, what can I do to get my results?

[Jean-Romain]

You can also process chunks of the point cloud and the raster yourself without using lidR in a loop. You sequentially crop and load 1x1 km of data in a loop. Alternatively you can try to fix the bug yourself. I'm currently in vacation and won't fix the bug until August.