Getting an error when using las2dem.exe?
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MAG
Mar 13, 2012, 5:59:50 AM3/13/12
to LAStools - efficient tools for LIDAR processing
I tried to create a DTM from 13 LAS filed using Las2dem.exe. I
receives the following error:
B:\Test_Area_3\PointCloud>las2dem -i tiles\*.las -merged -keep_class 2
-o dtm.asc
Please license from 'martin....@gmail.com' to use LAStools
commercially.
WARNING: unlicensed. over 10 million points. inserting black diagonal.
ERROR: failed malloc for 178004840 TINtriangles.
ERROR: cannot alloc enough TIN triangles to triangulate 89002420
points.
contact martin....@gmail.com for help on what to do.
/Morten Aggerholm
receives the following error:
B:\Test_Area_3\PointCloud>las2dem -i tiles\*.las -merged -keep_class 2
-o dtm.asc
Please license from 'martin....@gmail.com' to use LAStools
commercially.
WARNING: unlicensed. over 10 million points. inserting black diagonal.
ERROR: failed malloc for 178004840 TINtriangles.
ERROR: cannot alloc enough TIN triangles to triangulate 89002420
points.
contact martin....@gmail.com for help on what to do.
/Morten Aggerholm
Martin Isenburg
Mar 13, 2012, 8:37:13 AM3/13/12
to LAStools - efficient tools for LIDAR processing
Hello Morten,
BLAST. The best answer to rasterizing large point clouds is BLAST.
blast2dem -i tiles\*.las -merged -keep_class 2 -o dtm.asc
But you may also try the '-extra_pass' option.
las2dem -i tiles\*.las -merged -keep_class 2 -o dtm.asc -extra_pass
las2dem.exe is a "traditional" in-core algorithm that will first load
all the points into memory, then triangulate them, and then raster the
triangles into a DEM. Triangulating 89,002,420 points results in about
178,004,840 triangles. Since each point needs at least 12 bytes
storage and each triangle at least 28 bytes storage you cannot do this
for that many points/triangles given the 2GB main memory limitation of
a 32 bit windows executable.
blast2dem.exe is a streaming out-of-core algorithm that that will only
keep a fraction of the points in memory at any given time. it is
designed to triangulate points sets that are magnitudes larger than
the available main memory. it creates a seamless TIN that is identical
to that created by las2dem but streams the triangles through memory,
rasterizing the "fionalized" ones, and re-using their memory. If you
are interested this is described in more detail in these two
publications [1,2].
That said, since you are only triangulating the ground points with
classification 2 can also help las2dem.exe by setting the '-
extra_pass' flag. This will cause las2dem.exe to make two passes over
the LAS file. In the first pass it merely counts how many points will
actually be triangulated (i.e. have classification 2) and maybe the
remaining points will fit into memory.
Regards,
Martin @lastools
[1] Martin Isenburg, Yuanxin Liu, Jonathan Shewchuk, Jack Snoeyink,
Streaming Computation of Delaunay Triangulations, Proceedings of
SIGGRAPH'06, pages 1049-1056, July 2006. online at
http://www.cs.unc.edu/~isenburg/papers/ilss-scdt-06.pdf
[2] Martin Isenburg, Yuanxin Liu, Jonathan Shewchuk, Jack Snoeyink,
Tim Thirion, Generating Raster DEM from LiDAR via TIN Streaming,
GIScience'06 Conference Proceedings, pages 186-198, September 2006.
online at http://www.cs.unc.edu/~isenburg/papers/ilsst-tin2dem-06.pdf
On Mar 13, 2:59 am, MAG <mor...@mortenaggerholm.dk> wrote:
> I tried to create a DTM from 13 LAS filed using Las2dem.exe. I
> receives the following error:
>
> B:\Test_Area_3\PointCloud>las2dem -i tiles\*.las -merged -keep_class 2
> -o dtm.asc
>
> Please license from 'martin.isenb...@gmail.com' to use LAStools
>
> /Morten Aggerholm
BLAST. The best answer to rasterizing large point clouds is BLAST.
blast2dem -i tiles\*.las -merged -keep_class 2 -o dtm.asc
But you may also try the '-extra_pass' option.
las2dem -i tiles\*.las -merged -keep_class 2 -o dtm.asc -extra_pass
las2dem.exe is a "traditional" in-core algorithm that will first load
all the points into memory, then triangulate them, and then raster the
triangles into a DEM. Triangulating 89,002,420 points results in about
178,004,840 triangles. Since each point needs at least 12 bytes
storage and each triangle at least 28 bytes storage you cannot do this
for that many points/triangles given the 2GB main memory limitation of
a 32 bit windows executable.
blast2dem.exe is a streaming out-of-core algorithm that that will only
keep a fraction of the points in memory at any given time. it is
designed to triangulate points sets that are magnitudes larger than
the available main memory. it creates a seamless TIN that is identical
to that created by las2dem but streams the triangles through memory,
rasterizing the "fionalized" ones, and re-using their memory. If you
are interested this is described in more detail in these two
publications [1,2].
That said, since you are only triangulating the ground points with
classification 2 can also help las2dem.exe by setting the '-
extra_pass' flag. This will cause las2dem.exe to make two passes over
the LAS file. In the first pass it merely counts how many points will
actually be triangulated (i.e. have classification 2) and maybe the
remaining points will fit into memory.
Regards,
Martin @lastools
[1] Martin Isenburg, Yuanxin Liu, Jonathan Shewchuk, Jack Snoeyink,
Streaming Computation of Delaunay Triangulations, Proceedings of
SIGGRAPH'06, pages 1049-1056, July 2006. online at
http://www.cs.unc.edu/~isenburg/papers/ilss-scdt-06.pdf
[2] Martin Isenburg, Yuanxin Liu, Jonathan Shewchuk, Jack Snoeyink,
Tim Thirion, Generating Raster DEM from LiDAR via TIN Streaming,
GIScience'06 Conference Proceedings, pages 186-198, September 2006.
online at http://www.cs.unc.edu/~isenburg/papers/ilsst-tin2dem-06.pdf
On Mar 13, 2:59 am, MAG <mor...@mortenaggerholm.dk> wrote:
> I tried to create a DTM from 13 LAS filed using Las2dem.exe. I
> receives the following error:
>
> B:\Test_Area_3\PointCloud>las2dem -i tiles\*.las -merged -keep_class 2
> -o dtm.asc
>
> commercially.
> WARNING: unlicensed. over 10 million points. inserting black diagonal.
> ERROR: failed malloc for 178004840 TINtriangles.
> ERROR: cannot alloc enough TIN triangles to triangulate 89002420
> points.
> contact martin.isenb...@gmail.com for help on what to do.
> WARNING: unlicensed. over 10 million points. inserting black diagonal.
> ERROR: failed malloc for 178004840 TINtriangles.
> ERROR: cannot alloc enough TIN triangles to triangulate 89002420
> points.
>
> /Morten Aggerholm
Andrew
Mar 26, 2012, 3:43:55 PM3/26/12
to LAStools - efficient tools for LiDAR processing
Hi Martin,
Firstly, thank you for providing such a wonderful suite of tools for
manipulating LiDAR data files, I use lastools frequently and have
found your programs to be very useful, robust and efficient.
You mentioned in your reply the "2GB main memory limitation of a 32
bit windows executable". Given that that many of us are probably using
lastools on 64 bit Windows systems, would you consider compiling 64
bit versions of lastools and providing them as downloads?
As I understand it, 64 bit versions of lastools could utilise much
more RAM, up to 192GB on 64 Bit Windows 7 Professional for example.
This would allow much larger datasets to be processed by programs such
as las2dem.exe that use "traditional" in-core algorithms.
Is there any technical barriers that I am not aware of that would
prohibit compiling 64 bit versions of lastools?
Regards
Andrew Goodwin
> SIGGRAPH'06, pages 1049-1056, July 2006. online athttp://www.cs.unc.edu/~isenburg/papers/ilss-scdt-06.pdf
Firstly, thank you for providing such a wonderful suite of tools for
manipulating LiDAR data files, I use lastools frequently and have
found your programs to be very useful, robust and efficient.
You mentioned in your reply the "2GB main memory limitation of a 32
bit windows executable". Given that that many of us are probably using
lastools on 64 bit Windows systems, would you consider compiling 64
bit versions of lastools and providing them as downloads?
As I understand it, 64 bit versions of lastools could utilise much
more RAM, up to 192GB on 64 Bit Windows 7 Professional for example.
This would allow much larger datasets to be processed by programs such
as las2dem.exe that use "traditional" in-core algorithms.
Is there any technical barriers that I am not aware of that would
prohibit compiling 64 bit versions of lastools?
Regards
Andrew Goodwin
> [2] Martin Isenburg, Yuanxin Liu, Jonathan Shewchuk, Jack Snoeyink,
> Tim Thirion, Generating Raster DEM from LiDAR via TIN Streaming,
> GIScience'06 Conference Proceedings, pages 186-198, September 2006.
> online athttp://www.cs.unc.edu/~isenburg/papers/ilsst-tin2dem-06.pdf
> Tim Thirion, Generating Raster DEM from LiDAR via TIN Streaming,
> GIScience'06 Conference Proceedings, pages 186-198, September 2006.
Martin Isenburg
Mar 28, 2012, 7:30:24 AM3/28/12
to LAStools - efficient tools for LiDAR processing
Hi Andrew,
> Firstly, thank you for providing such a wonderful suite of tools for
> manipulating LiDAR data files, I use lastools frequently and have
> found your programs to be very useful, robust and efficient.
Thank you for the compliments. I will let my development team know ...
(-;
> You mentioned in your reply the "2GB main memory limitation of a 32
> bit windows executable". Given that that many of us are probably using
> lastools on 64 bit Windows systems, would you consider compiling 64
> bit versions of lastools and providing them as downloads?
If the need becomes really really really pressing i will eventually
compile on 64 bit. But I do not have such hardware myself. In fact, I
am still working on a 2005 Dell Inspiron laptop that I have since the
days I did my postdoc at UC Berkeley ... (-:
I like to claim that I limit my hardware on purpose. One of the
reasons that LAStools are so fast and memory efficient is that my
algorithms try to get maximal efficiency out of the minimal hardware
that I develop them on.
> Is there any technical barriers that I am not aware of that would
> prohibit compiling 64 bit versions of lastools?
Not that I am aware of ... although my core triangulation algorithm is
pointer based. To again minimize the memory footprint it would then be
good to rewrite the internal pointer-based structure to use 32 bit
integer indexing to avoid increasing the memory footprint as compiling
on 64 bit will make all pointers grow from 32 to 64 bit.
Cheers,
Martin @lastools
> Firstly, thank you for providing such a wonderful suite of tools for
> manipulating LiDAR data files, I use lastools frequently and have
> found your programs to be very useful, robust and efficient.
(-;
> You mentioned in your reply the "2GB main memory limitation of a 32
> bit windows executable". Given that that many of us are probably using
> lastools on 64 bit Windows systems, would you consider compiling 64
> bit versions of lastools and providing them as downloads?
compile on 64 bit. But I do not have such hardware myself. In fact, I
am still working on a 2005 Dell Inspiron laptop that I have since the
days I did my postdoc at UC Berkeley ... (-:
I like to claim that I limit my hardware on purpose. One of the
reasons that LAStools are so fast and memory efficient is that my
algorithms try to get maximal efficiency out of the minimal hardware
that I develop them on.
> Is there any technical barriers that I am not aware of that would
> prohibit compiling 64 bit versions of lastools?
pointer based. To again minimize the memory footprint it would then be
good to rewrite the internal pointer-based structure to use 32 bit
integer indexing to avoid increasing the memory footprint as compiling
on 64 bit will make all pointers grow from 32 to 64 bit.
Cheers,
Martin @lastools
Message has been deleted
Herne, Natasha
Mar 29, 2012, 9:40:44 AM3/29/12
to last...@googlegroups.com
Martin:
I follow LAStools mail trail since I am trying to learn and understand the capabilities of the software you produced.
As I am a field biologist brought to work with GIS and LiDAR, I was so happy to read the msg below.
The msg struck another realm!!!!
Sustainability in the cyber world!!!! Inspiring!!!!!
Thank you!!
Natasha Herne
Natural Resources Planning and Management Division
Broward County Environmental Protection and Growth Management Department
115 South Andrews Avenue, Fort Lauderdale, Florida 33301
Office: 954-519-1436
Martin wrote:
Hi Andrew,
Cheers,
Martin @lastools
--
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http://lastools.org/
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http://groups.google.com/group/lastools/
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Charles Cowart
Mar 29, 2012, 3:59:33 PM3/29/12
to last...@googlegroups.com
Hi Martin, Andrew,
FYI, we were able to successfully compile and run lastools on 64-bit Linux platforms with no modification to the source.
Cheers,
Charles Cowart
OpenTopography.org
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