[GRASS-user] LiDAR LAS import

Markus Metz markus.metz.giswork at googlemail.com
Thu Nov 24 11:59:21 EST 2011


Daniel Victoria wrote:
> Hi Rebecca et al.,
>
> I'm having the same problem. Installed liblas using ubuntu packages
> and when I run configure I get that it's unable to locate libLAS
> library.
>
> daniel at daniel-desktop:/usr/lib$ liblas-config --libs
> -L/usr/lib -lgeotiff -L/usr/lib -lgdal1.6.0
> daniel at daniel-desktop:/usr/lib$ liblas-config --includes
> -I/usr/include/geotiff -I/usr/include/gdal
>
> Has anyone figured out what is going on?

Another try: where is liblas.h located on your system? I remember that
I did not find documentation about how to include liblas C-API
headers, so I did trial-and-error and found that

#include <liblas/capi/liblas.h>

worked, i.e. the header file liblas.h is (in common configurations)
located either in /usr/include/liblas/capi/ or in
/usr/local/include/liblas/capi/

Can you confirm that?

Markus M

>
> Thanks
> Daniel
>
>
> On Fri, Jul 29, 2011 at 8:10 AM, Rebecca Bennett <rabennett at ymail.com> wrote:
>> sorry for the delayed reply - (windoze day yesterday)
>>>Hmm. Is lasinfo --help working?
>> Yes. wont paste the output here but it is as expected.
>>
>>>liblas-config --libs
>> -L/usr/lib -lgeotiff -L/usr/lib -lgdal1.6.0
>>>liblas-config --includes
>> -I/usr/include/geotiff -I/usr/include/gdal
>>
>> Thanks,
>>
>> Rebecca
>>
>> ________________________________
>> From: Markus Metz <markus.metz.giswork at googlemail.com>
>> To: Rebecca Bennett <rabennett at ymail.com>
>> Cc: "grass-user at lists.osgeo.org" <grass-user at lists.osgeo.org>
>> Sent: Wednesday, 27 July 2011, 18:01
>> Subject: Re: [GRASS-user] LiDAR LAS import
>>
>> On Wed, Jul 27, 2011 at 3:28 PM, Rebecca Bennett <rabennett at ymail.com>
>> wrote:
>>> sure -
>>>
>>> checking whether to use libLAS... yes
>>> checking for liblas-config... /usr/bin/liblas-config
>>> configure: error: *** Unable to locate libLAS library.
>>>
>>> I have the packages liblas1, liblas-dev, lib-las-bin and python-liblas
>>> installed through synaptic and am wondering if there is a libraty package
>>> missing?
>>
>> Hmm. Is lasinfo --help working?
>>
>> What does
>> liblas-config --libs
>> and
>> liblas-config --includes
>> say?
>>
>>
>>>
>>> ________________________________
>>> From: Markus Metz <markus.metz.giswork at googlemail.com>
>>> To: Rebecca Bennett <rabennett at ymail.com>
>>> Cc: "grass-user at lists.osgeo.org" <grass-user at lists.osgeo.org>
>>> Sent: Wednesday, 27 July 2011, 13:16
>>> Subject: Re: [GRASS-user] LiDAR LAS import
>>>
>>> Rebecca Bennett wrote:
>>>> Hello,
>>>> Just trying to install GRASS 7 on Ubuntu 10.04 to try out the las import
>>>> functions but I'm getting error messages during the configure that it is
>>>> unable to find the liblas library, however the liblas library is
>>>> installed
>>>> in usr/bin/lib/ so I'm a bit puzzled...
>>>
>>> Can you post the exact error message? Also, liblas support will only
>>> be available if liblas-config exists.
>>>
>>> Markus M
>>>
>>>> Did anyone else get stuck here or am I missing something obvious?
>>>> Thanks for reading,
>>>> Rebecca
>>>>
>>>> ________________________________
>>>> From: Markus Metz <markus.metz.giswork at googlemail.com>
>>>> To: Hamish <hamish_b at yahoo.com>
>>>> Cc: grass-user <grass-user at lists.osgeo.org>; GRASS developers list
>>>> <grass-dev at lists.osgeo.org>
>>>> Sent: Wednesday, 25 May 2011, 12:48
>>>> Subject: Re: [GRASS-user] LiDAR LAS import
>>>>
>>>> On Wed, May 25, 2011 at 12:16 PM, Hamish <hamish_b at yahoo.com> wrote:
>>>>> Markus Metz wrote:
>>>>>> Hi all,
>>>>>>
>>>>>> GRASS 7 has a new module v.in.lidar for importing LiDAR LAS files
>>>>>> (*.las or *.laz). The LAS file format is commonly used for storing
>>>>>> LiDAR point clouds, but is unfortunately not supported by OGR.
>>>>>> v.in.lidar uses the libLAS library [0] and is only compiled if the
>>>>>> libLAS library is present.
>>>>>>
>>>>>> I chose to use the library instead of writing a custom LAS reading
>>>>>> interface because the current LAS library version 1.6.1 is stable,
>>>>>> supports LAS file versions 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, each of
>>>>>> which can store LiDAR points in up to 5 different point formats. The
>>>>>> user and the interface do not need to know the file version and point
>>>>>> format of a given file, all that is conveniently handled by the libLAS
>>>>>> library in the background. The library has Large File Support (LFS)
>>>>>> and is well tested on different platforms, also with different
>>>>>> endian-ness. This functionality is not that easy to replicate.
>>>>>>
>>>>>> You will need to get the libLAS library and configure GRASS 7 with
>>>>>> --with-liblas in order to have the module available. Please test!
>>>>>>
>>>>>> Markus M
>>>>>>
>>>>>> [0] http://www.liblas.org
>>>>>
>>>>>
>>>>> neat! any time trials to say how much faster it is than piping
>>>>>  las2txt | v.in.ascii
>>>>> ?
>>>>
>>>> Note that las2txt does NOT apply scale and offset to x,y,z, this would
>>>> need to be done afterwards in order to obtain correct coordinates.
>>>> Therefore the output of las2txt | v.in.ascii with the sample las file
>>>> I used is incorrect.
>>>>
>>>> I discovered a bug in v.in.ascii: from a point file with | as field
>>>> separator like
>>>>
>>>> 1|2|3||5|6
>>>>
>>>> only the first 3 columns will be imported because column 4 is empty
>>>> which means that columns 5 and 6 are skipped.
>>>>
>>>> v.in.lidar is a notch faster than las2txt | v.in.ascii. And easier to
>>>> use...
>>>> Speed comparisons:
>>>>
>>>> # sample las file with 1,287,775 points
>>>>
>>>> # with table and topology
>>>> time las2txt -i points.las --stdout --parse xyztinrcCpedRGBau
>>>> --delimiter "|" | v.in.ascii in=- out=points_ascii -z x=1 y=2 z=3 --o
>>>>
>>>> real    6m34.430s
>>>> user    4m57.530s
>>>> sys    2m3.693s
>>>>
>>>> time v.in.lidar in=points.las out=points_las -o --o
>>>>
>>>> real    6m13.823s
>>>> user    4m32.061s
>>>> sys    2m1.068s
>>>>
>>>>
>>>> # without table, with topology
>>>> time las2txt -i points.las --stdout --parse xyz --delimiter "|" |
>>>> v.in.ascii in=- out=points_ascii -zt x=1 y=2 z=3 --o
>>>>
>>>> real    1m53.578s
>>>> user    1m47.032s
>>>> sys    0m9.238s
>>>>
>>>> time v.in.lidar in=points.las out=points_las -ot --o
>>>>
>>>> real    1m44.876s
>>>> user    1m34.450s
>>>> sys    0m8.488s
>>>> _______________________________________________
>>>> grass-user mailing list
>>>> grass-user at lists.osgeo.org
>>>> http://lists.osgeo.org/mailman/listinfo/grass-user
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> grass-user mailing list
>>>> grass-user at lists.osgeo.org
>>>> http://lists.osgeo.org/mailman/listinfo/grass-user
>>>>
>>>>
>>>
>>>
>>>
>>
>>
>>
>> _______________________________________________
>> grass-user mailing list
>> grass-user at lists.osgeo.org
>> http://lists.osgeo.org/mailman/listinfo/grass-user
>>
>>
>


More information about the grass-user mailing list