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  lasmerge: merge multiple LAS files into a single file
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:Author: Martin Isenburg
:Contact: isenburg@cs.unc.edu
:Revision: $Revision$
:Date: $Date$

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lasmerge reads multiple LIDAR data files in the LAS format and merges them 
into a single file. The filenames can either be provided one by one or in 
form of a text file.

All the header information of the first file provided is used including 
variable and user_defined headers. but some records are updated by 
integrating the corresponding information from other headers. these are:

* number_of_point_records
* number_of_points_by_return[5]
* max_x, min_x, max_y, min_y, max_z, and min_z

In addition x_scale_factor, y_scale_factor, z_scale_factor may need to be 
increased to accommodate a possibly larger bounding box. The user can 
also set those in the command line with

  -scale 0.01     or     -scale_xyz  0.01 0.01 0.001

Similarly a new offset can be specified

  -xyz_offset 63025000 483450000 0

Usage
-----

::

  $ lasmerge -i in1.las -i in2.las -i in3.las -o out.las

merge the three inX.las files into one out.las file. 

::

  $ lasmerge -i las_file_list.txt -o out.las

merges all LAS files listed in the text file into one out.las file

::

  $ lasmerge -i las_file_list.txt -o out.las -scale 0.01 -verbose

merges the file and stores the LIDAR points with 0.01 accuracy in x, y, and 
z and prints out control information.

::

  $ lasmerge -i las_file_list.txt -o out.las -scale_xyz 0.01 0.01 0.001

same but with a different accuracy for z.

Help
~~~~

::

    C:\lastools\bin>lasmerge -h
    usage:
    lasmerge -i lasfiles.txt -o out.las
    lasmerge -i file1.las -i file2.las -i file3.las -o out.las
    lasmerge -i file1.las -i file2.las -olas > out.las
    lasmerge -i lasfiles.txt -scale 0.01 -verbose -o out.las
    lasmerge -h
