lasvoxel_README.txt

****************************************************************

  lasvoxel:

  This tool computes a voxelization of points. You can specify the
  xy and the z size of the voxel cells separately with '-step_xy 2'
  and '-step_z 0.3' which would create cells of size 2 by 2 by 0.3
  units or use uniform sized cells of '-step 0.5'. For voxels that
  are infinite in z direction use option '-step_z_infinite'. The
  number of returns falling into a voxel is stored as the intensity
  value of the points in the resulting LAS/LAZ file.

  By adding '-compute_mean_xyz' to the command line lasvoxel uses
  the average x, y, z coordinate of all points falling into a voxel
  instead of the center of the voxel.

  By adding '-empty_voxels' to the command line lasvoxel will also
  report all empty voxels that fall within the 3D bounding box but
  give them an intensity value of zero.

  Please license from martin@rapidlasso.com before using lasvoxel
  commercially. Please note that the unlicensed version will set
  intensity, gps_time, user data, and point source ID to zero,
  slightly change the LAS point order, and randomly add a tiny
  bit of white noise to the points coordinates once a certain
  number of points in the input file is exceeded.

  For updates check the website or join the LAStools mailing list.

  http://rapidlasso.com/
  http://lastools.org/
  http://groups.google.com/group/lastools/
  http://twitter.com/lastools/
  http://facebook.com/lastools/
  http://linkedin.com/groups?gid=4408378

  Martin @rapidlasso

****************************************************************

example usage:

>> lasvoxel -v ^
            -i ..\data\france.laz ^
            -i ..\data\fusa.laz ^
            -step 1 ^
            -odix _mist -olaz

voxelizing 101206 points with step_xy 1 units and step_z 1 units ...
took 0.063 sec. created 15 vertical layers. outputting ...
done with '..\data\france_mist.laz'. took 0.078 sec.
voxelizing 277573 points with step_xy 1 m and step_z 1 m ...
took 0.186 sec. created 23 vertical layers. outputting ...
done with '..\data\fusa_mist.laz'. took 0.241 sec.
done with all files. total time for 2 files 0.319 sec.


>> lastile -i shitloadoflidar.laz ^
           -tile_size 10 ^
           -odir tiles -o small.laz

>> lasvoxel -i tiles/small*.laz ^
            -odir result -olaz

>> lasmerge -i result/small*.laz ^
            -o big_result.laz

the above workflow is for larger areas and/or tiny voxels sizes

****************************************************************

overview of all tool-specific switches:

-v                                   : more info reported in console
-vv                                  : even more info reported in console
-quiet                               : nothing reported in console
-version                             : reports this tool's version number
-fail                                : fail if license expired or invalid
-gui                                 : start with files loaded into GUI
-cores 4                             : process multiple inputs on 4 cores in parallel
-ignore_class 1 3 4 5 6 7 9          : ignores points with specified classification codes
-step 1.0                            : use 1 x 1 x 1 uniform grid for finding isolated points
-step_xy 2.0                         : set the horizontal x and y spacing of the grid to 2
-step_z 0.5                          : set the vertical z spacing of the grid to 0.5
-step_z_infinite                     : sets the vertical z spacing to infinite (-> one layer of voxels)
-compute_mean_xyz                    : compute averaged coordinate for output voxels
-empty_voxels                        : also output voxels without returns but give them intensity of zero
-compute_IDs_and_voxel_table         : https://groups.google.com/d/topic/lastools/Nc-rN5OuxY8/discussion
-ilay                                : apply all LASlayers found in corresponding *.lay file on read
-ilay 3                              : apply first three LASlayers found in corresponding *.lay file on read
-ilaydir E:\my_layers                : look for corresponding *.lay file in directory E:\my_layers
-olay                                : write or append classification changes to a LASlayers *.lay file
-olaydir E:\my_layers                : write the output *.lay file in directory E:\my_layers

****************************************************************

for more info:

C:\software\LAStools\bin>lasvoxel -h
Filter points based on their coordinates.
  -keep_tile 631000 4834000 1000 (ll_x ll_y size)
  -keep_circle 630250.00 4834750.00 100 (x y radius)
  -keep_xy 630000 4834000 631000 4836000 (min_x min_y max_x max_y)
  -drop_xy 630000 4834000 631000 4836000 (min_x min_y max_x max_y)
  -keep_x 631500.50 631501.00 (min_x max_x)
  -drop_x 631500.50 631501.00 (min_x max_x)
  -drop_x_below 630000.50 (min_x)
  -drop_x_above 630500.50 (max_x)
  -keep_y 4834500.25 4834550.25 (min_y max_y)
  -drop_y 4834500.25 4834550.25 (min_y max_y)
  -drop_y_below 4834500.25 (min_y)
  -drop_y_above 4836000.75 (max_y)
  -keep_z 11.125 130.725 (min_z max_z)
  -drop_z 11.125 130.725 (min_z max_z)
  -drop_z_below 11.125 (min_z)
  -drop_z_above 130.725 (max_z)
  -keep_xyz 620000 4830000 100 621000 4831000 200 (min_x min_y min_z max_x max_y max_z)
  -drop_xyz 620000 4830000 100 621000 4831000 200 (min_x min_y min_z max_x max_y max_z)
Filter points based on their return numbering.
  -keep_first -first_only -drop_first
  -keep_last -last_only -drop_last
  -keep_second_last -drop_second_last
  -keep_first_of_many -keep_last_of_many
  -drop_first_of_many -drop_last_of_many
  -keep_middle -drop_middle
  -keep_return 1 2 3
  -drop_return 3 4
  -keep_single -drop_single
  -keep_double -drop_double
  -keep_triple -drop_triple
  -keep_quadruple -drop_quadruple
  -keep_number_of_returns 5
  -drop_number_of_returns 0
Filter points based on the scanline flags.
  -drop_scan_direction 0
  -keep_scan_direction_change
  -keep_edge_of_flight_line
Filter points based on their intensity.
  -keep_intensity 20 380
  -drop_intensity_below 20
  -drop_intensity_above 380
  -drop_intensity_between 4000 5000
Filter points based on classifications or flags.
  -keep_class 1 3 7
  -drop_class 4 2
  -keep_extended_class 43
  -drop_extended_class 129 135
  -drop_synthetic -keep_synthetic
  -drop_keypoint -keep_keypoint
  -drop_withheld -keep_withheld
  -drop_overlap -keep_overlap
Filter points based on their user data.
  -keep_user_data 1
  -drop_user_data 255
  -keep_user_data_below 50
  -keep_user_data_above 150
  -keep_user_data_between 10 20
  -drop_user_data_below 1
  -drop_user_data_above 100
  -drop_user_data_between 10 40
Filter points based on their point source ID.
  -keep_point_source 3
  -keep_point_source_between 2 6
  -drop_point_source 27
  -drop_point_source_below 6
  -drop_point_source_above 15
  -drop_point_source_between 17 21
Filter points based on their scan angle.
  -keep_scan_angle -15 15
  -drop_abs_scan_angle_above 15
  -drop_abs_scan_angle_below 1
  -drop_scan_angle_below -15
  -drop_scan_angle_above 15
  -drop_scan_angle_between -25 -23
Filter points based on their gps time.
  -keep_gps_time 11.125 130.725
  -drop_gps_time_below 11.125
  -drop_gps_time_above 130.725
  -drop_gps_time_between 22.0 48.0
Filter points based on their RGB/CIR/NIR channels.
  -keep_RGB_red 1 1
  -drop_RGB_red 5000 20000
  -keep_RGB_green 30 100
  -drop_RGB_green 2000 10000
  -keep_RGB_blue 0 0
  -keep_RGB_nir 64 127
  -keep_NDVI 0.2 0.7 -keep_NDVI_from_CIR -0.1 0.5
  -keep_NDVI_intensity_is_NIR 0.4 0.8 -keep_NDVI_green_is_NIR -0.2 0.2
Filter points based on their wavepacket.
  -keep_wavepacket 0
  -drop_wavepacket 3
Filter points based on extra attributes.
  -keep_attribute_above 0 5.0
  -drop_attribute_below 1 1.5
Filter points with simple thinning.
  -keep_every_nth 2 -drop_every_nth 3
  -keep_random_fraction 0.1
  -keep_random_fraction 0.1 4711
  -thin_with_grid 1.0
  -thin_pulses_with_time 0.0001
  -thin_points_with_time 0.000001
Boolean combination of filters.
  -filter_and
Transform coordinates.
  -translate_x -2.5
  -scale_z 0.3048
  -rotate_xy 15.0 620000 4100000 (angle + origin)
  -translate_xyz 0.5 0.5 0
  -translate_then_scale_y -0.5 1.001
  -transform_helmert -199.87,74.79,246.62
  -transform_helmert 598.1,73.7,418.2,0.202,0.045,-2.455,6.7
  -transform_affine 0.9999652,0.903571,171.67,736.26
  -switch_x_y -switch_x_z -switch_y_z
  -clamp_z_below 70.5
  -clamp_z 70.5 72.5
  -copy_attribute_into_z 0
  -add_attribute_to_z 1
  -add_scaled_attribute_to_z 1 -1.2
  -copy_intensity_into_z
  -copy_user_data_into_z
Transform raw xyz integers.
  -translate_raw_z 20
  -translate_raw_xyz 1 1 0
  -translate_raw_xy_at_random 2 2
  -clamp_raw_z 500 800
Transform intensity.
  -set_intensity 0
  -scale_intensity 2.5
  -translate_intensity 50
  -translate_then_scale_intensity 0.5 3.1
  -clamp_intensity 0 255
  -clamp_intensity_above 255
  -map_intensity map_file.txt
  -copy_RGB_into_intensity
  -copy_NIR_into_intensity
  -copy_attribute_into_intensity 0
  -bin_gps_time_into_intensity 0.5
Transform scan_angle.
  -set_scan_angle 0.0
  -scale_scan_angle 1.944445
  -translate_scan_angle -5
  -translate_then_scale_scan_angle -0.5 2.1
Change the return number or return count of points.
  -repair_zero_returns
  -set_return_number 1
  -set_extended_return_number 10
  -change_return_number_from_to 2 1
  -change_extended_return_number_from_to 2 8
  -set_number_of_returns 2
  -set_extended_number_of_returns 15
  -change_number_of_returns_from_to 0 2
  -change_extended_number_of_returns_from_to 8 10
Modify the classification.
  -set_classification 2
  -set_extended_classification 41
  -change_classification_from_to 2 4
  -classify_z_below_as -5.0 7
  -classify_z_above_as 70.0 7
  -classify_z_between_as 2.0 5.0 4
  -classify_intensity_above_as 200 9
  -classify_intensity_below_as 30 11
  -classify_intensity_between_as 500 900 15
  -classify_attribute_below_as 0 -5.0 7
  -classify_attribute_above_as 1 70.0 7
  -classify_attribute_between_as 1 2.0 5.0 4
  -change_extended_classification_from_to 6 46
  -move_ancient_to_extended_classification
Change the flags.
  -set_withheld_flag 0
  -set_synthetic_flag 1
  -set_keypoint_flag 0
  -set_overlap_flag 1
Modify the extended scanner channel.
  -set_scanner_channel 2
  -copy_user_data_into_scanner_channel
Modify the user data.
  -set_user_data 0
  -scale_user_data 1.5
  -change_user_data_from_to 23 26
  -change_user_data_from_to 23 26
  -map_user_data map_file.txt
  -copy_attribute_into_user_data 1
  -add_scaled_attribute_to_user_data 0 10.0
Modify the point source ID.
  -set_point_source 500
  -change_point_source_from_to 1023 1024
  -map_point_source map_file.txt
  -copy_user_data_into_point_source
  -copy_scanner_channel_into_point_source
  -merge_scanner_channel_into_point_source
  -split_scanner_channel_from_point_source
  -bin_Z_into_point_source 200
  -bin_abs_scan_angle_into_point_source 2
  -bin_gps_time_into_point_source 5.0
Transform gps_time.
  -set_gps_time 113556962.005715
  -translate_gps_time 40.50
  -adjusted_to_week
  -week_to_adjusted 1671
Transform RGB/NIR colors.
  -set_RGB 255 0 127
  -set_RGB_of_class 9 0 0 255
  -scale_RGB 2 4 2
  -scale_RGB_down (by 256)
  -scale_RGB_up (by 256)
  -switch_R_G -switch_R_B -switch_B_G
  -copy_R_into_NIR -copy_R_into_intensity
  -copy_G_into_NIR -copy_G_into_intensity
  -copy_B_into_NIR -copy_B_into_intensity
  -copy_intensity_into_NIR
  -switch_RGBI_into_CIR
  -switch_RGB_intensity_into_CIR
Transform attributes in "Extra Bytes".
  -scale_attribute 0 1.5
  -translate_attribute 1 0.2
  -copy_user_data_into_attribute 0
Supported LAS Inputs
  -i lidar.las
  -i lidar.laz
  -i lidar1.las lidar2.las lidar3.las -merged
  -i *.las - merged
  -i flight0??.laz flight1??.laz
  -i terrasolid.bin
  -i esri.shp
  -i nasa.qi
  -i lidar.txt -iparse xyzti -iskip 2 (on-the-fly from ASCII)
  -i lidar.txt -iparse xyzi -itranslate_intensity 1024
  -lof file_list.txt
  -stdin (pipe from stdin)
  -rescale 0.01 0.01 0.001
  -rescale_xy 0.01 0.01
  -rescale_z 0.01
  -reoffset 600000 4000000 0
Fast AOI Queries for LAS/LAZ with spatial indexing LAX files
  -inside min_x min_y max_x max_y
  -inside_tile ll_x ll_y size
  -inside_circle center_x center_y radius
Supported LAS Outputs
  -o lidar.las
  -o lidar.laz
  -o xyzta.txt -oparse xyzta (on-the-fly to ASCII)
  -o terrasolid.bin
  -o nasa.qi
  -odir C:\data\ground (specify output directory)
  -odix _classified (specify file name appendix)
  -ocut 2 (cut the last two characters from name)
  -olas -olaz -otxt -obin -oqfit (specify format)
  -stdout (pipe to stdout)
  -nil    (pipe to NULL)
LAStools (by martin@rapidlasso.com) version 190812 (commercial)
usage:
lasvoxel -i in.laz -o out.laz
lasvoxel -i in.laz -step 2 -o out.laz
lasvoxel -i in.laz -step_xy 2 -step_z 1 -o out.laz
lasvoxel -i in.laz -step_xy 4 -step_z 2 -max_count 65535 -o out.laz
lasvoxel -i in.laz -step_xy 1 -step_z_infinite -o out.laz
lasvoxel -i in.laz -step 2.5 -compute_IDs_and_voxel_table -o out.laz
lasvoxel -i in.laz -step 2.5 -compute_IDs_and_voxel_table -store_IDs_in_intensity -o out.laz
lasvoxel -h

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if you find bugs let me (martin@rapidlasso.com) know.