[GRASS-user] LiDAR LAS import

[Markus Metz]

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
>>
>>
>
>
>