Hi Jochen,
hi all,
I'm trying to convert my laz files to TIF. I'm supplied mostly 1x1 km tiles, but at state borders, the files smaller. Now I have a problem with the buffering and the TIFs for incomplete laz files.
My Workflow is as follows:
> preparing a file list of laz files from different folders via cmd in windows
> lasindex
^
-lof file_list.txt
^
-cores 4
>
lasgrid
^
-lof file_list.txt
^
-cpu64
^
-cores 4
^
-mem 2000
^
-subcircle 0.2
^
-use_orig_bb
^
-buffered 2
^
-otif
^
-nclos
1000
^
-nrows 1000
^
-average
^
-odir XX
Now I got two issues:
1:
Since most of my laz files have 1mio points with 1000 rows and 1000 colums, I'd expect them to get some 8000 points from the buffer on top (buffered 2). Is that assumption right? In the command promt, I messages like these:
LASreaderBuffered: adding 6009 buffer points.
GeographicTypeGeokey: look-up for 4258 not implemented
GeogGeodeticDatumGeoKey: look-up for 6258 not implemented
Can you shed some light on this? 6K points mean I get buffers on three sides, not four?
2:
Since my original laz points are on the lower left corner of every pixel I use nrows/ncols 1000 to fill also the last row and column. If I don't do that I always get an empty last column and row.
So far so good, the TIFs look alright for for inner-state tiles.
For files at state borders, which are typically not 1x1km, I get some issues with lasgrid. In the following example, I have a half filled laz file (~1kmx0.5km)
But here, in the final TIFs, the buffer points from outside are also rendered as pixels. I guess this is because lasgrid tries to reach 1000 rows/cols as I told it and I takes the buffer as well?
In my example I'd want my TIF to be rendered from row 0 to 1000 and col 500 to 1000.
How could I tackle that?
Example of a half filled file:
Zoom in on the upper left border:
Thx and kind regards
Peter