# lasview

A simple OpenGL-based viewer for LIDAR in LAS/LAZ/ASCII format
that can also edit or delete points as well as compute/display
a TIN computed from (a selection of) the points.

EDITING & DELETING POINTS

Press [e] to start r[e]classifying point as noise (7). Use the
pop-up menu (right click) to select other target classes. Draw
a polygon enclosing some points and press [r] to register the
operation. With [ESC] you can unset the last polygon point and
with [CTRL+u] you can undo the operation or with [CTRL+o] redo
it again.

Press [d] to start [d]eleting points. Otherwise same procedure
as above.

When finished press [CTRL+s] to save the edits as LASlayers in
to a LAY file. Warning ... if you did not start lasview with
the '-ilay' option you will not append to an existing LAY file
but overwrite it. There will be a WARNING though. Later, you
can check your layers of edits with 'laslayers.exe' or view
and continue editing with the '-ilay' option when starting
lasview again.

If you want to apply your edits and creating a new file press
[CTRL-a] and an entirely new file (currently with "_1" at the
end of the input file name) is created.

Do not use lasview with on-the-fly filters or transforms when
you plan to do editing operations that you are going to save.

VIEWING AND TRAVERSING CROSS SECTIONS 

For quality checking and detail views you can press [x] and
select a cross section or smaller area of interest. By default
you will draw a profile rectangle. Holding down [SHIFT] draws
a profile line. Its width can be chosen in the pop-up menu. Move
either around with the arrow key. Holding down [SHIFT] or [ALT]
is taking larger or smaller steps. Press [x] again and you see
only the selected area. Again, traverse the LiDAR my moving
around with the arrow keys. You can do your edits in this
cross section view. Jumping back between cross section view
and the full extend with [x] help maintaining orientation.

With [CTRL-x] you can end the cross section view.


## Examples

    lasview lidar.las
    lasview -i lidar.las

reads around 1000000 subsampled lidar points and displays in 50 steps


    lasview *.las

merges all LAS files into one and displays a subsampling of it


    lasview -i lidar.txt -iparse xyzc

converts an ASCII file on-the-fly with parse string 'xyzc' and displays it


    lasview -i lidar.las -win 1600 1200

same as above but with a larger display window


    lasview -i lidar.las -steps 10 -points 10000000

reads around 10 million subsampled lidar points and displays in 11 steps


## Interactive options

[t]     compute a TIN from the displayed returns  
[T]     remove the TIN [SHIFT]+[t]  
[h]     change shading mode for TIN (hill-shade, elevation, wire-frame)  
[G]     show rasterization "needles" for grid set by '-grid n' value [SHIFT]+[g]  
[R]     raster TIN with grid cell size set by '-grid n' value [SHIFT]+[r]  
  
[y]     take one step of spike-free algorithm (press many times to see algorithm in action)  
[Y]     complete spike-free algorithm to end [SHIFT]+[y]  
  
[a]     display all returns  
[l]     display last returns only  
[f]     display first returns only  
[g]     display returns classified as ground  
[b]     display returns classified as building  
[B]     display returns classified as building + ground [SHIFT]+[b]  
[v]     display returns classified as vegetation  
[V]     display returns classified as vegetation + ground [SHIFT]+[v]  
[j]     display returns classified as building + vegetation  
[J]     display returns classified as building + vegetation + ground [SHIFT]+[j]  
[m]     display returns classified as keypoints / mass points  
[n]     display returns classified as noise  
[o]     display returns classified as overlap  
[w]     display returns classified as water  
[u]     display returns that are unclassified  
[0]     display ((point source IDs % 8) == 0)  
[1]     display ((point source IDs % 8) == 1)  
[2]     display ((point source IDs % 8) == 2)  
[3]     display ((point source IDs % 8) == 3)  
[4]     display ((point source IDs % 8) == 4)  
[5]     display ((point source IDs % 8) == 5)  
[6]     display ((point source IDs % 8) == 6)  
[7]     display ((point source IDs % 8) == 7)  
  
[e]      start editing points  
[d]      start deleting points  
[r]      register edit / delete operation  
  
[CTRL-u] undo last changes  
[CTRL-o] redo last undo  
  
[CTRL-s] save changes as LASlayers  
[CTRL-f] force LAY file overwrite  
[CTRL-a] apply LASlayers to create new LAS/LAZ file  
  
[i]       pick a point  
[I]       pick a point and draw line to last picked point [SHIFT]+[i]  
[x]       turn on and toggle between overview and rectangle / line cross-section   
[SHIFT]   hold down to pick line instead of rectangle cross-section when in overview   
[CTRL-x]  overview and rectangle / line cross-section view on / off  
  
[SHIFT] translate mode  
[CTRL]  zoom mode  
[ALT]   pan mode  
[space] switch between pan/translate/zoom/tilt  
[-/=]   render points smaller/bigger  
[[/]]   scale elevation  
[{/}]   scale xy plane  
[c]     change color mode  
[X]     hide/show bounding box [SHIFT]+[x]  
[s/S]   step forward/backward  
[z/Z]   tiny step forward/backward  
  
[A]     toggle adaptive Z-scaling on/off [SHIFT]+[a]  
[Q]     show spatial index structure (if LAX file available) [SHIFT]+[q]  
[q]     pick spatial index cell  
[E]     render structural elements around all points [SHIFT]+[e]  
[:]     decrease structural element radius  
["]     increase structural element radius  
[W]     show LAS 1.3 waveforms +/- 25 points around picked point [SHIFT]+[w]


## lasview specific arguments

-background_black                   : start viewer with a black background  
-background_blue                    : start viewer with a blue background  
-background_green                   : start viewer with a green background  
-background_grey                    : start viewer with a grey background  
-background_red                     : start viewer with a red background  
-background_white                   : start viewer with a white background  
-buildings                          : render only points classified as building  
-bulge [n]                          : bulge sloped neighbourhoods of TIN triangles by [n]{default=step/10}  
-camera 0 -59 -24 0 -0.0572 0.385   : move virtual camera to specifies parameters (print parameters with [K] or [SHIFT]+[k])  
-circles [n]                        : define structural elements as circles of radius [n]  
-color_by_classification            : render points by classification color  
-color_by_elevation1                : render points by elevation color ramp (black-red-yellow-white)  
-color_by_elevation2                : render points by elevation color ramp (blue-yellow-red)  
-color_by_flightline                : render points by randomly assigning 8 different colors based on the flightline ID  
-color_by_intensity                 : render points by intensity  
-color_by_return                    : render points by return colors (single = yellow, first of many = red, last of many = blue, intermediate = green)  
-color_by_rgb                       : render points by RGB color  
-color_by_user_data                 : render points by mapping the 8-bit user data field to a color ramp (blue-]green-]red)  
-concavity [n]                      : remove large exterior triangles from TIN who have an edge longer [n]{default=50}  
-cones [m] [n]                      : define structural elements as cones of radius [m] and height [n]  
-cp [fnt]                           : load control points with parse string xyz from file [fnt] and visualize each as red sphere with radius 1 meter  
-cp_parse [xyz]                     : use parse string [xyz] to parse control point file  
-every [n]                          : visualize incremental loading of points every [n] points  
-flats [m] [n] [o]                  : define structural elements as flats of small radius [m], height [n] and large radius [o]  
-grid [n]                           : set raster spacing [n] for visualization of rasterization with [R] {default=1}  
-ground                             : render only points classified as ground  
-ground_buildings                   : render only points classified as ground or building  
-ground_object                      : render only points classified as ground, vegetation, or building  
-ground_vegetation                  : render only points classified as ground or vegetation  
-holes [n]                          : remove any triangle from TIN that has an edge length bigger than [n]  
-ilay [n]                           : apply [n] or all LASlayers found in corresponding *.lay file on read  
-ilaydir [n]                        : look for corresponding *.lay file in directory [n]  
-kamera [x] [y] [z] [dx] [dy] [dz]  : move virtual camera to specified parameters (print parameters with [K] or [SHIFT]+[k])  
-kill [n]                           : remove any triangle from TIN that has an edge length bigger than [n]  
-light [x] [y] [z]                  : set light direction vector to [x] [y] [z] for hillshaded TIN  
-load_gps_second                    : also loads GPS time stamps from file and displays them when pressing [i]  
-load_gps_time                      : also loads GPS time stamps from file and displays them when pressing [i]  
-mark_down_spike [n]                : set markers at TIN spikes larger than [n]  
-mark_down_spike2 [m] [n]           : set markers at TIN spikes larger than [m] within a distance of [n]  
-mark_point [n]                     : surround point at position [n] in file with a pink sphere of 0.5 meter radius  
-no_bounding_box                    : do not render the green bounding box  
-object                             : render only points classified as vegetation or building  
-olaydir [n]                        : write the output *.lay file (from editing) in directory [n]  
-only_first                         : render only first returns  
-only_last                          : render only last returns  
-only_multi                         : render only multiple returns  
-only_single                        : render only single returns  
-pit_free                           : run spike-free algorithm with defaults freeze = 1.5, interval = 0.25, buffer = 0.5  
-point_size [n]                     : draw points with size [n]  
-points [n]                         : load maximally [n] points from file (with regular sub sampling)(default=5 mil.)  
-points_all                         : force to load all points (otherwise: skip points on input larger than 5 mio points)  
-profile_line [x1] [y1] [x2] [y2]   : run in profile line mode with bounding box [x1] [y1] [x2] [y2]  
-profile_rectangle [x1] [y1] [x2] [y2]: run in profile rectangle mode with bounding box [x1] [y1] [x2] [y2]  
-reversed                           : run spike-free in reverse (from bottom to top)  
-scale_rgb                          : down-scale 16 bit RGB values for storage to 8 bit RGB values (usually auto-detected).  
-screenshot [n]                     : create a screenshot and save in file [n]  
-set_min_max [m] [n]                : clamp color ramp used for elevation colorings to range [m] [n] instead of (min-max)  
-spike_free                         : run spike-free algorithm with defaults freeze = 1.5, interval = 0.25, buffer = 0.5  
-spike_free [m] [n] [o]             : run spike-free algorithm with freeze = [m], interval = [n], buffer = [o]  
-start_at_point [n]                 : start loading from point position [n]  
-steep [n]                          : remove all "steep" triangles from the TIN with z values spanning more than [n] meters  
-steps [n]                          : visualize incremental loading of points from file in [n] steps (default=50)  
-stop_at_point [n]                  : stop loading after [n] points  
-subcircle [n]                      : prior to creating TIN with [t] replace each point with 8 segment circle of radius [n]  
-subseq [m] [n]                     : only load subsequence from point [m] to [n]  
-suppress_classification            : do not decompress classification for native-compressed LAS 1.4 point types 6 or higher  
-suppress_intensity                 : do not decompress intensity for native-compressed LAS 1.4 point types 6 or higher  
-suppress_point_source              : do not decompress point source ID for native-compressed LAS 1.4 point types 6 or higher  
-suppress_RGB                       : do not decompress RGB for native-compressed LAS 1.4 point types 6 or higher  
-suppress_user_data                 : do not decompress user data field for native-compressed LAS 1.4 point types 6 or higher  
-suppress_z                         : do not decompress z coordinates for native-compressed LAS 1.4 point types 6 or higher  
-switch_G_B                         : switch green and blue value  
-vegetation                         : render only points classified as vegetation  
-week_to_adjusted [n]               : converts time stamps from GPS week [n] to Adjusted Standard GPS  
-win [m] [n]                        : start with render window size of [m] by [n] pixels  

### Basics
-cores [n]      : process multiple inputs on [n] cores in parallel  
-h, -help       : print help output  
-v, -verbose    : verbose output (print extra information)  
-vv             : very verbose output (print even more information)  
-silent         : only output on errors or warnings  
-quiet          : no output at all  
-force          : continue, even if serious warnings occur  
-errors_ignore  : continue, even if errors occur (if possible). Use with caution!  
-print_log_stats: print additional log statistics  
-cpu64          : force 32bit version to start 64 bit in multi core (obsolete)  
-gui            : start with files loaded into GUI  
-version        : reports this tool's version number  


## Module arguments

### General
-comma_not_point   : use comma instead of point as decimal separator  
-neighbors [n]     : set neighbors filename or wildcard [n]  
-neighbors_lof [n] : set neighbors list of files [fnf]  
-stored            : use in memory reader  

### Color
-clamp_RGB_to_8bit                  : limit RGB values to 8 bit (otherwise: 16 bit)  
-copy_B_into_NIR                    : copy blue color value into NearInfraRed value  
-copy_B_into_intensity              : copy blue color value to intensity  
-copy_B_into_register [n]           : copy blue color value into register [n]  
-copy_G_into_NIR                    : copy green color value into NearInfraRed value  
-copy_G_into_intensity              : copy green color value to intensity  
-copy_G_into_register [n]           : copy green color value into register [n]  
-copy_NIR_into_intensity            : copy NIR into intensity  
-copy_NIR_into_register [n]         : copy NearInfraRed value into register [n]  
-copy_RGB_into_intensity            : copy weighted RGB value to intensity  
-copy_R_into_NIR                    : copy red color value into NearInfraRed value  
-copy_R_into_intensity              : copy red color value to intensity  
-copy_R_into_register [n]           : copy red color value into register [n]  
-copy_attribute_into_B [n]          : copy attribute [n] value into blue  
-copy_attribute_into_G [n]          : copy attribute [n] value into green  
-copy_attribute_into_NIR [n]        : copy attribute [n] value into NIR (NearInfraRed)  
-copy_attribute_into_R [n]          : copy attribute [n] value into red  
-copy_intensity_into_NIR            : copy intensity into NIR (NearInfraRed) value  
-copy_register_into_B [n]           : copy register [n] into blue color value  
-copy_register_into_G [n]           : copy register [n] into green color value  
-copy_register_into_I [n]           : copy register [n] into NearInfraRed value  
-copy_register_into_NIR [n]         : copy register [n] into NearInfraRed value  
-copy_register_into_R [n]           : copy register [n] into red color value  
-drop_RGB_green [min] [max]         : drop points with green color value between [min] and [max]  
-drop_RGB_red [min] [max]           : drop points with red color value between [min] and [max]  
-force_RGB                          : force the use of the RGB value even if the point format does not support RGB  
-keep_NDVI [min] [max]              : keep NDVI (Normalized Difference Vegetation Index) between [min] [max]  
-keep_NDVI_from_CIR [min] [max]     : keep NDVI (Normalized Difference Vegetation Index) from CIR between [min] [max]  
-keep_NDVI_green_is_NIR [min] [max] : keep NDVI (Normalized Difference Vegetation Index) where green is NIR between [min] [max]  
-keep_NDVI_blue_is_NIR [min] [max]  : keep NDVI (Normalized Difference Vegetation Index) where blue is NIR between [min] [max]  
-keep_NDVI_intensity_is_NIR [min] [max]: keep NDVI (Normalized Difference Vegetation Index) where intensity is NIR between [min] [max]  
-keep_RGB_blue [m] [n]              : keep points with RGB blue color values between [min] [max]  
-keep_RGB_green [min] [max]         : keep points with green color value between [min] and [max]  
-keep_RGB_greenness [m] [n]         : keep points with RGB greenness values between [min] [max]  
-keep_RGB_nir [m] [n]               : keep points with RGB NIR values between [min] [max]  
-keep_RGB_red [min] [max]           : keep points with red color value between [min] and [max]  
-map_attribute_into_RGB [a] [fnm]   : map attribute [a] by table in file [fnm] to RGB values  
-scale_NIR [n]                      : scale NearInfraRed value by factor [n]  
-scale_NIR_down                     : scale NearInfraRed value down by 256  
-scale_NIR_to_16bit                 : scale 8 bit NearInfraRed value to 16 bit  
-scale_NIR_to_8bit                  : scale 16 bit NearInfraRed value downto 8 bit  
-scale_NIR_up                       : scale NearInfraRed value up by 256  
-scale_RGB [r] [g] [b]              : scale RGB values by factors in [r][g][b]  
-scale_RGB_down                     : scale RGB color values down by 256  
-scale_RGB_to_16bit                 : scale 8 bit color values to 16 bit  
-scale_RGB_to_8bit                  : scale 16 bit color values downto 8 bit  
-scale_RGB_up                       : scale RGB values from 8 bit up to 16 bit (multiply with 256)  
-scale_rgb_down                     : divides all RGB values by 256 (to go from 16 bit to 8 bit numbers)  
-scale_rgb_up                       : multiplies all RGB values by 256 (to go from 8 bit to 16 bit numbers)  
-set_NIR [n]                        : set NearInfraRed value to [n]  
-set_RGB [r] [g] [b]                : set color to [r] [g] [b]  
-set_RGB_of_class [c] [r] [g] [b]   : set RGB values of class [c] to [r][g][b] (8 or 16 bit)  
-switch_RGBI_into_CIR               : set R to NIR; G to R; B to G  
-switch_RGB_intensity_into_CIR      : set R to intensity; G to R; B to G  
-switch_R_B                         : switch red and blue color value  
-switch_R_G                         : switch red and green color value  

### Coordinates
-add_attribute_to_z [n]             : add value of attribute [n] to z value  
-add_scaled_attribute_to_z [m] [n]  : scale attribute [m] value by [n] and add to z value  
-auto_reoffset                      : puts a reasonable offset in the header and translates the points accordingly. Only applicable to LAS/LAZ input files  
-bin_Z_into_point_source [n]        : set point source to z/[n]  
-clamp_raw_z [min] [max]            : limit raw z values to [min] and [max]  
-clamp_z [min] [max]                : limit z values to [min] and [max]  
-clamp_z_above [n]                  : limit z values to maximal [n]  
-clamp_z_below [n]                  : limit z values to minimal [n]  
-classify_z_above_as [m] [n]        : for z value above [m] set class to [n]  
-classify_z_below_as [m] [n]        : for z value below [m] set class to [n]  
-classify_z_between_as [m] [n] [o]  : for z value between [m] and [n] set class to [o]  
-copy_attribute_into_x [n]          : copy attribute [n] value into x  
-copy_attribute_into_y [n]          : copy attribute [n] value into y  
-copy_attribute_into_z [n]          : copy attribute [n] value into z  
-copy_intensity_into_z              : copy intensity to z value  
-copy_register_into_x [n]           : copy register [n] to x value  
-copy_register_into_y [n]           : copy register [n] to y value  
-copy_register_into_z [n]           : copy register [n] to z value  
-copy_user_data_into_z              : copy user data into z  
-copy_z_into_attribute [n]          : copy z value into attribute [n] value  
-drop_x [m] [n]                     : drop points with x value between [m] and [n]  
-drop_x_above [n]                   : drop points with x value above [n]  
-drop_x_below [n]                   : drop points with x value below [n]  
-drop_xy [x1] [y1] [x2] [y2]        : drop points within the [x1] [y1] [x2] [y2] rectangle  
-drop_xyz [x1] [y1] [z1] [x2] [y2] [z2]: drop points within the given cube dimensions  
-drop_y [m] [n]                     : drop points with y value between [m] and [n]  
-drop_y_above [n]                   : drop points with y value above [n]  
-drop_y_below [n]                   : drop points with y value below [n]  
-drop_z [m] [n]                     : drop points with z value between [m] and [n]  
-drop_z_above [n]                   : drop points with z value above [n]  
-drop_z_below [n]                   : drop points with z value below [n]  
-inside [x1] [y1] [x2] [y2]         : use only points within the [x1] [y1] [x2] [y2] rectangle  
-inside_circle [x] [y] [r]          : keep circle at pos [x] [y] with radius [r]  
-inside_rectangle [x1] [y1] [x2] [y2]: use only points within the [x1] [y1] [x2] [y2] rectangle  
-inside_tile [m] [n] [o]            : use only points inside tile at lower-left [x] [y] with size [s]  
-keep_circle [x] [y] [r]            : keep circle at pos [x] [y] with radius [r]  
-keep_profile [x1] [y1] [x2] [y2] [w]: keep profile with [x1] [y1] [x2] [y2] [w]  
-keep_tile [x] [y] [size]           : keep tile at lower-left [x] [y] with size [s]  
-keep_x [m] [n]                     : keep points with x value between [m] and [n]  
-keep_xy [x1] [y1] [x2] [y2]        : keep points within the [x1] [y1] [x2] [y2] rectangle  
-keep_xyz [x1] [y1] [z1] [x2] [y2] [z2]: keep points within the given cube dimensions  
-keep_y [m] [n]                     : keep points with y value between [m] and [n]  
-keep_z [m] [n]                     : keep points with z value between [m] and [n]  
-keep_z_above [n]                   : keep points with z value above [n]  
-keep_z_below [n]                   : keep points with z value below [n]  
-offset_adjust                      : adjusting the offset based on the results of point operations and transformations  
-reoffset [x] [y] [z]               : puts a new offset [x] [y] [z] into the header and translates the points accordingly  
-rescale [x] [y] [z]                : puts a new scale [x] [y] [z] into the header and rescales the points accordingly  
-rescale_xy [x] [y]                 : rescale x y by [x] [y]  
-rescale_z [z]                      : rescale z by [z]  
-rotate_xy [a] [x] [y]              : rotate points by [a] degrees, center at [x] [y]  
-rotate_xz [a] [x] [z]              : rotate points by [a] degrees, center at [x] [z]  
-rotate_yz [a] [y] [z]              : rotate points by [a] degrees, center at [y] [z]  
-scale_x [n]                        : scale x value by [n]  
-scale_xyz [m] [n] [o]              : scale xyz values by [m] [n] [o]  
-scale_y [n]                        : scale y value by [n]  
-scale_z [n]                        : scale z value by [n]  
-switch_x_y                         : exchange x and y value  
-switch_x_z                         : exchange x and z value  
-switch_y_z                         : exchange z and x value  
-transform_affine [k,w,x,y]         : transform by k*cos(w)+k*sin(w)+tx;k*cos(w)+k*sin(w)+ty - angle in second of arc  
-transform_helmert [m] [n] [o]      : do a helmert transformation with 3 or 7 comma separated parameters [n] ...  
-transform_matrix [r11,r12,r13] [r21,r22,r23] [r31,r32,r33] [tr1,tr2,tr3]: transform input using matrix [r11,r12,r13] [r21,r22,r23] [r31,r32,r33] [tr1,tr2,tr3]  
-translate_raw_x [n]                : translate raw x value by [n]  
-translate_raw_xy_at_random [x] [y] : translate raw xy values by random and max offset of [x] [y]  
-translate_raw_xyz [x] [y] [z]      : translate raw coordinates by [x] [y] [z]  
-translate_raw_y [n]                : translate raw y value by [n]  
-translate_raw_z [n]                : translate raw z value by [n]  
-translate_scale_translate_x [m] [n]: calculate x value as (x–[m])*[n]+[m]  
-translate_scale_translate_y [m] [n]: calculate y value as (y–[m])*[n]+[m]  
-translate_scale_translate_z [m] [n]: calculate z value as (z–[m])*[n]+[m]  
-translate_then_scale_x [m] [n]     : translate x value by [m] and scale by [n]  
-translate_then_scale_y [m] [n]     : translate y value by [m] and scale by [n]  
-translate_then_scale_z [m] [n]     : translate z value by [m] and scale by [n]  
-translate_x [n]                    : translate y value by [n]  
-translate_xyz [x] [y] [z]          : translate point coordinates by [x] [y] [z]  
-translate_y [n]                    : translate y value by [n]  
-translate_z [n]                    : translate z value by [n]  

### Simple thinning
-drop_every_nth [n]           : drop every [n]th point  
-keep_every_nth [n]           : keep every [n]th point  
-keep_random_fraction [m] [n] : keep points by random fraction [m]{0-1}, optional seed [n]  
-thin_points_with_time [n]    : thin points with time, [n] = timespacing  
-thin_pulses_with_time [n]    : thin pulses with time, [n] = timespacing  
-thin_with_grid [n]           : thin points by min grid size of [n]  
-thin_with_time [n]           : thin pulses with time, [n] = timespacing  

### Return number
-change_extended_number_of_returns_from_to [m] [n]: change extended number of returns from [m] to [n]  
-change_extended_return_number_from_to [m] [n]: change extended return number from [m] to [n]  
-change_number_of_returns_from_to [m] [n]: change number of returns from [m] to [n]  
-change_return_number_from_to [m] [n]: change return number from [m] to [n]  
-drop_double                        : drop double returns  
-drop_first                         : drop first return  
-drop_first_of_many                 : drop first of many returns  
-drop_last                          : drop last return  
-drop_last_of_many                  : drop last of many returns  
-drop_middle                        : drop middle returns  
-drop_number_of_returns [n]         : drop points with [n] number of returns  
-drop_quadruple                     : drop quadruple returns  
-drop_quintuple                     : drop quintuple returns  
-drop_return [m] [n]...             : drop points with return [m] [n]...  
-drop_return_mask [n]               : drop points with return mask [n]  
-drop_second_last                   : drop points with second last return  
-drop_single                        : drop points with single return  
-drop_triple                        : drop points with triple return  
-first_only                         : use first return only  
-keep_double                        : keep double returns  
-keep_first                         : keep first return  
-keep_first_of_many                 : keep first of many returns  
-keep_last                          : keep last return  
-keep_last_of_many                  : keep last of many returns  
-keep_middle                        : keep mittle returns  
-keep_number_of_returns [n]         : keep points with [n] number of returns  
-keep_quadruple                     : keep quadruple returns  
-keep_quintuple                     : keep quintuple returns  
-keep_return [m] [n]...             : keep points with return [m] [n]...  
-keep_return_mask [n]               : keep points with return mask [n]  
-keep_second_last                   : keep points with second last return  
-keep_single                        : keep points with single return  
-keep_triple                        : keep points with triple return  
-last_only                          : use last return only  
-repair_zero_returns                : sets return counts and number of returns that are zero to one  
-set_extended_number_of_returns [n] : set extended number of returns to [n]  
-set_extended_return_number [n]     : set extended return number to [n]  
-set_number_of_returns [n]          : set number of returns to [n]  
-set_return_number [n]              : set return number to [n]  

### Scanline
-drop_scan_direction [n]       : drop points with scan direction [n]  
-faf                           : input files are flightlines. do ***NOT*** use this for tiled input  
-faf_index [n]                 : set files are flightlines index [n]  
-files_are_flightlines         : input files are flightlines. do ***NOT*** use this for tiled input  
-drop_edge_of_flight_line      : drop points with "Edge of Flight Line" flag set  
-keep_edge_of_flight_line      : keep points with "Edge of Flight Line" flag set  
-keep_scan_direction_change    : keep points with changed scan direction flag  
-set_edge_of_flight_line [0/1] : set "Edge of Flight Line" flag to [0/1]  
-set_scan_direction_flag [0/1] : set scan direction flag to [0/1]  

### Scanner channel
-copy_scanner_channel_into_point_source: copy scanner channel into point_source  
-copy_scanner_channel_into_user_data: copy scanner channel into user data  
-copy_user_data_into_scanner_channel: copy user data into scanner channel  
-drop_scanner_channel [n]           : drop points with scanner channel [n]  
-keep_scanner_channel [n]           : keep points with scanner channel [n]  
-merge_scanner_channel_into_point_source: merge scanner channel to point source  
-set_extended_scanner_channel [n]   : set extended scanner channel to [n]  
-set_scanner_channel [n]            : set scanner channel to [n]  
-split_scanner_channel_from_point_source: split scanner channel from point source and save as extended scanner channel  

### Source ID
-apply_file_source_ID               : copy file source ID to target  
-bin_Z_into_point_source [n]        : set point source to z/[n]  
-bin_abs_scan_angle_into_point_source [n]: set point source to scan_angle/[n]  
-bin_gps_time_into_point_source [n] : set point source to gps/[n]  
-change_point_source_from_to [m] [n]: change point source from [m] to [n]  
-copy_attribute_into_point_source [n]: copy attribute [n] value into point source  
-copy_classification_into_point_source: copy classification to point source  
-copy_point_source_into_register [n]: copy point source into register [n]  
-copy_register_into_point_source [n]: copy register [n] to point source  
-copy_scanner_channel_into_point_source: copy scanner channel into point_source  
-copy_user_data_into_point_source   : copy user data into point source  
-drop_point_source [n]              : drop points with point source [n]  
-drop_point_source_above [n]        : drop points with with point source above [n]  
-drop_point_source_below [n]        : drop points with with point source below [n]  
-drop_point_source_between [m] [n]  : drop points with with point source between [n] and [m]  
-keep_point_source [n]              : keep points with point source [n]  
-keep_point_source_between [m] [n]  : keep points with with point source between [n] and [m]  
-map_point_source [fnm]             : set the point source by map in file [fnm]  
-merge_scanner_channel_into_point_source: merge scanner channel to point source  
-set_point_source [n]               : set point source to [n]  
-split_scanner_channel_from_point_source: split scanner channel from point source and save as extended scanner channel  

### User data
-add_scaled_attribute_to_user_data [m] [n]: scale attribute [m] value by [n] and add to user data  
-change_user_data_from_to [m] [n]   : change user data from [m] to [n]  
-copy_attribute_into_user_data [n]  : copy attribute [n] value into user data field  
-copy_classification_into_user_data : copy classification to user data  
-copy_register_into_user_data [n]   : copy register [n] to user data  
-copy_scanner_channel_into_user_data: copy scanner channel into user data  
-copy_user_data_into_attribute [n]  : copy user data into attribute [n] value  
-copy_user_data_into_classification : copy user data into classification  
-copy_user_data_into_point_source   : copy user data into point source  
-copy_user_data_into_register [n]   : copy user data to register [n]  
-copy_user_data_into_scanner_channel: copy user data into scanner channel  
-copy_user_data_into_z              : copy user data into z  
-drop_user_data [n]                 : drop points with user data value of [n]  
-drop_user_data_above [n]           : drop points with user data value above [n]  
-drop_user_data_below [n]           : drop points with user data value below [n]  
-drop_user_data_between [m] [n]     : drop points with user data between [m] and [n]  
-keep_user_data [n]                 : keep points with user data value of [n]  
-keep_user_data_above [n]           : keep points with user data value above [n]  
-keep_user_data_below [n]           : keep points with user data value below [n]  
-keep_user_data_between [m] [n]     : keep points with user data between [m] and [n]  
-map_user_data [fnm]                : set the user data by map in file [fnm]  
-scale_user_data [n]                : scale user data by [n]  
-set_user_data [n]                  : sets all user_data fields to [n]  

### Classification
-change_class_from_to [m] [n]       : change classification from [m] to [n]  
-change_classification_from_to [m] [n]: change classification from [m] to [n]  
-change_extended_class_from_to [m] [n]: change extended class from [m] to [n]  
-change_extended_classification_from_to [m] [n]: change extended class from [m] to [n]  
-classify_attribute_above_as [m] [n] [o]: for attribute [m] with value above [n] set class to [o]  
-classify_attribute_below_as [m] [n] [o]: for attribute [m] with value below [n] set class to [o]  
-classify_attribute_between_as [m] [n] [o] [p]: for attribute [m] with value between [n] and [o] set class to [p]  
-classify_intensity_above_as [m] [n]: for intensity value above [m] set class to [n]  
-classify_intensity_below_as [m] [n]: for intensity value below [m] set class to [n]  
-classify_intensity_between_as [m] [n] [o]: for intensity value between [m] and [n] set class to [o]  
-classify_z_above_as [m] [n]        : for z value above [m] set class to [n]  
-classify_z_below_as [m] [n]        : for z value below [m] set class to [n]  
-classify_z_between_as [m] [n] [o]  : for z value between [m] and [n] set class to [o]  
-copy_classification_into_point_source: copy classification to point source  
-copy_classification_into_user_data : copy classification to user data  
-copy_intensity_into_classification : copy intensity to classification  
-copy_user_data_into_classification : copy user data into classification  
-drop_class [m] [n] [o]...          : drop points with class in [m][n][o]...  
-drop_classification [m] [n] [o]... : drop points with class in [m][n][o]...  
-drop_classification_mask [n]       : drop points with classification mask matches [n]  
-drop_extended_class [m] [n]...     : drop extended class [m] [n]...  
-drop_extended_classification [n]   : drop points with extended classification [n]  
-drop_extended_classification_mask [a] [b] [c] [d] [e] [f] [g] [h]: drop points with extended classification mask matches [a] [b] [c] [d] [e] [f] [g] [h]  
-keep_class [m] [n] [o]...          : keep points with class in [m][n][o]...  
-keep_classification [m] [n] [o]... : keep points with class in [m][n][o]...  
-keep_classification_mask [n]       : keep points with classification mask matches [n]  
-keep_extended_class [m] [n]...     : keep extended class [m] [n]...  
-keep_extended_classification [n]   : keep points with extended class [n]  
-move_ancient_to_extended_classification: move old data to extended classification  
-set_RGB_of_class [c] [r] [g] [b]   : set RGB values of class [c] to [r][g][b] (8 or 16 bit)  
-set_classification [n]             : set classification to [n]  
-set_extended_classification [n]    : set extended classification to [n]  

### Extra byte
-add_attribute_to_z [n]             : add value of attribute [n] to z value  
-add_scaled_attribute_to_user_data [m] [n]: scale attribute [m] value by [n] and add to user data  
-add_scaled_attribute_to_z [m] [n]  : scale attribute [m] value by [n] and add to z value  
-classify_attribute_above_as [m] [n] [o]: for attribute [m] with value above [n] set class to [o]  
-classify_attribute_below_as [m] [n] [o]: for attribute [m] with value below [n] set class to [o]  
-classify_attribute_between_as [m] [n] [o] [p]: for attribute [m] with value between [n] and [o] set class to [p]  
-copy_attribute_into_B [n]          : copy attribute [n] value into blue  
-copy_attribute_into_G [n]          : copy attribute [n] value into green  
-copy_attribute_into_I [n]          : copy attribute [n] value into intensity  
-copy_attribute_into_NIR [n]        : copy attribute [n] value into NIR (NearInfraRed)  
-copy_attribute_into_R [n]          : copy attribute [n] value into red  
-copy_attribute_into_intensity [n]  : copy attribute [n] value into intensity  
-copy_attribute_into_point_source [n]: copy attribute [n] value into point source  
-copy_attribute_into_register [m] [n]: copy attribute [m] value into register [m]  
-copy_attribute_into_user_data [n]  : copy attribute [n] value into user data field  
-copy_attribute_into_x [n]          : copy attribute [n] value into x  
-copy_attribute_into_y [n]          : copy attribute [n] value into y  
-copy_attribute_into_z [n]          : copy attribute [n] value into z  
-copy_intensity_into_attribute [n]  : copy intensity to attribute [n] value  
-copy_register_into_attribute [m] [n]: copy register [m] to attribute [n] value  
-copy_user_data_into_attribute [n]  : copy user data into attribute [n] value  
-copy_z_into_attribute [n]          : copy z value into attribute [n] value  
-drop_attribute_above [m] [n]       : drop points with attribute [m] value > [n]  
-drop_attribute_below [m] [n]       : drop points with attribute [m] value < [n]  
-drop_attribute_between [m] [n] [o] : drop points with attribute [m] in range [n]...[o]  
-iadd_attribute [m] [n] [o] [p] [q] [r] [s] [t]: adds a new "extra_byte" attribute of data_type [m] name [n] description [o]; optional: scale[p] offset [q] pre_scale [r] pre_offset [s] no_data_value [t]  
-iadd_extra [m] [n] [o] [p] [q] [r] [s] [t]: adds a new "extra_byte" attribute of data_type [m] name [n] description [o]; optional: scale[p] offset [q] pre_scale [r] pre_offset [s] no_data_value [t]  
-keep_attribute_above [m] [n]       : keep points with attribute [m] value > [n]  
-keep_attribute_below [m] [n]       : keep points with attribute [m] value < [n]  
-keep_attribute_between [m] [n] [o] : keep points with attribute [m] in range [n]...[o]  
-load_attribute_from_text [m] [fnt] : load attribute [m] from file [fnt]  
-map_attribute_into_RGB [a] [fnm]   : map attribute [a] by table in file [fnm] to RGB values  
-scale_attribute [m] [n]            : scale attribute [m] by [n]  
-set_attribute [m] [n]              : set attribute [m] with value [n]  
-translate_attribute [m] [n]        : translate attribute [n] by [n]  

### Flags
-drop_keypoint                   : drop points flaged as keypoint  
-drop_overlap                    : drop points flaged as overlap  
-drop_scan_direction [n]         : drop points with scan direction [n]  
-drop_synthetic                  : drop points flaged as synthetic  
-drop_withheld                   : drop points flaged as withheld  
-keep_edge_of_flight_line        : keep points with "Edge of Flight Line" flag set  
-keep_keypoint                   : keep points flaged as keypoint  
-keep_overlap                    : keep points flaged as overlap  
-keep_scan_direction_change      : keep points with changed scan direction flag  
-keep_synthetic                  : keep points flaged as synthetic  
-keep_withheld                   : keep points flaged as withheld  
-set_edge_of_flight_line [0/1]   : set "Edge of Flight Line" flag to [0/1]  
-set_extended_overlap_flag [0/1] : set extended overlap flag to [0/1]  
-set_keypoint_flag [0/1]         : set keypoint flag to [0/1]  
-set_overlap_flag [0/1]          : set overlap flag to [0/1]  
-set_scan_direction_flag [0/1]   : set scan direction flag to [0/1]  
-set_synthetic_flag [0/1]        : set synthetic flag to [0/1]  
-set_withheld_flag [0/1]         : set withheld flag to [0/1]  

### GPS time
-adjusted_to_week                   : converts time stamps from Adjusted Standard GPS to GPS week  
-bin_gps_time_into_intensity [n]    : set intensity time to gps/[n]  
-bin_gps_time_into_point_source [n] : set point source to gps/[n]  
-drop_gps_time_above [n]            : drop points with GPS time above [n]  
-drop_gps_time_below [n]            : drop points with GPS time below [n]  
-drop_gps_time_between [m] [n]      : drop points with GPS time between [m] and [n]  
-drop_gpstime_above [n]             : drop points with GPS time above [n]  
-drop_gpstime_below [n]             : drop points with GPS time below [n]  
-drop_gpstime_between [m] [n]       : drop points with GPS time between [m] and [n]  
-keep_gps_time [m] [n]              : keep points with GPS time between [m] and [n]  
-keep_gps_time_above [n]            : keep points with GPS time above [n]  
-keep_gps_time_below [n]            : keep points with GPS time below [n]  
-keep_gps_time_between [m] [n]      : keep points with GPS time between [m] and [n]  
-keep_gpstime [m] [n]               : keep points with GPS time between [m] and [n]  
-keep_gpstime_above [n]             : keep points with GPS time above [n]  
-keep_gpstime_below [n]             : keep points with GPS time below [n]  
-keep_gpstime_between [m] [n]       : keep points with GPS time between [m] and [n]  
-set_gps_time [n]                   : set gps time to [n]  
-translate_gps_time [n]             : translate GPS time by [n]  

### Intensity
-bin_gps_time_into_intensity [n]    : set intensity time to gps/[n]  
-clamp_intensity [min] [max]        : limit intensity values to [min] and [max]  
-clamp_intensity_above [max]        : limit intensity values to maximal [max]  
-clamp_intensity_below [max]        : limit intensity values to minimal [min]  
-classify_intensity_above_as [m] [n]: for intensity value above [m] set class to [n]  
-classify_intensity_below_as [m] [n]: for intensity value below [m] set class to [n]  
-classify_intensity_between_as [m] [n] [o]: for intensity value between [m] and [n] set class to [o]  
-copy_B_into_intensity              : copy blue color value to intensity  
-copy_G_into_intensity              : copy green color value to intensity  
-copy_NIR_into_intensity            : copy NIR into intensity  
-copy_RGB_into_intensity            : copy weighted RGB value to intensity  
-copy_R_into_intensity              : copy red color value to intensity  
-copy_attribute_into_I [n]          : copy attribute [n] value into intensity  
-copy_attribute_into_intensity [n]  : copy attribute [n] value into intensity  
-copy_intensity_into_NIR            : copy intensity into NIR (NearInfraRed) value  
-copy_intensity_into_attribute [n]  : copy intensity to attribute [n] value  
-copy_intensity_into_classification : copy intensity to classification  
-copy_intensity_into_register [n]   : copy color intensitiy value into register [n]  
-copy_intensity_into_z              : copy intensity to z value  
-copy_register_into_intensity [n]   : copy register [n] into point intensitiy value  
-drop_intensity_above [n]           : drop points with intensity value above [n]  
-drop_intensity_below [n]           : drop points with intensity value below [n]  
-drop_intensity_between [m] [n]     : drop points with intensity value between [m] and [n]  
-iscale_intensity [n]               : scale intensity value by [n]  
-itranslate_intensity [n]           : translate input intensity by [n]  
-keep_NDVI_intensity_is_NIR [min] [max]: keep NDVI (Normalized Difference Vegetation Index) where intensity is NIR between [min] [max]  
-keep_intensity [m] [n]             : keep points with intensity between [m] and [n]  
-keep_intensity_above [n]           : keep points with intensity value above [n]  
-keep_intensity_below [n]           : keep points with intensity value below [n]  
-map_intensity [fnm]                : set the intensity by map in file [fnm]  
-scale_intensity [n]                : multiply intensity by [n]  
-set_intensity [n]                  : set intensity to [n]  
-switch_RGB_intensity_into_CIR      : set R to intensity; G to R; B to G  
-translate_intensity [n]            : translate intensity by [n]  
-translate_then_scale_intensity [m] [n]: translate intensity by [m] and scale by [n]  

### Raw point values
-clamp_raw_z [min] [max]            : limit raw z values to [min] and [max]  
-translate_raw_x [n]                : translate raw x value by [n]  
-translate_raw_xy_at_random [x] [y] : translate raw xy values by random and max offset of [x] [y]  
-translate_raw_xyz [x] [y] [z]      : translate raw coordinates by [x] [y] [z]  
-translate_raw_y [n]                : translate raw y value by [n]  
-translate_raw_z [n]                : translate raw z value by [n]  

### Registers
-add_registers [m] [n] [o]          : add register [m] and [n] and store result in register [o]  
-copy_B_into_register [n]           : copy blue color value into register [n]  
-copy_G_into_register [n]           : copy green color value into register [n]  
-copy_NIR_into_register [n]         : copy NearInfraRed value into register [n]  
-copy_R_into_register [n]           : copy red color value into register [n]  
-copy_attribute_into_register [m] [n]: copy attribute [m] value into register [m]  
-copy_intensity_into_register [n]   : copy color intensitiy value into register [n]  
-copy_point_source_into_register [n]: copy point source into register [n]  
-copy_register_into_B [n]           : copy register [n] into blue color value  
-copy_register_into_G [n]           : copy register [n] into green color value  
-copy_register_into_I [n]           : copy register [n] into NearInfraRed value  
-copy_register_into_NIR [n]         : copy register [n] into NearInfraRed value  
-copy_register_into_R [n]           : copy register [n] into red color value  
-copy_register_into_attribute [m] [n]: copy register [m] to attribute [n] value  
-copy_register_into_intensity [n]   : copy register [n] into point intensitiy value  
-copy_register_into_point_source [n]: copy register [n] to point source  
-copy_register_into_user_data [n]   : copy register [n] to user data  
-copy_register_into_x [n]           : copy register [n] to x value  
-copy_register_into_y [n]           : copy register [n] to y value  
-copy_register_into_z [n]           : copy register [n] to z value  
-copy_user_data_into_register [n]   : copy user data to register [n]  
-divide_registers [m] [n] [o]       : divide register [m] by register [n] and store result in register [o]  
-multiply_registers [m] [n] [o]     : Multiply register [m] with [n] and store result in register [o]  
-scale_register [m] [n]             : scale register index [m] with factor [n]  
-set_register [m] [n]               : set register [m] with value [n]  
-subtract_registers [m] [n] [o]     : subtract register [m] by register [n] and store result in register [o]  
-translate_register [m] [n]         : translate register index [m] value by [n]  

### Scan angle
-bin_abs_scan_angle_into_point_source [n]: set point source to scan_angle/[n]  
-drop_abs_scan_angle_above [max]    : drop points with absolute scan angle above [max]  
-drop_abs_scan_angle_below [min]    : drop points with absolute scan angle below [min]  
-drop_scan_angle_above [n]          : drop points with scan angle above [n]  
-drop_scan_angle_below [n]          : drop points with scan angle below [n]  
-drop_scan_angle_between [m] [n]    : drop points with scan angle between [m] and [n]  
-iscale_scan_angle [n]              : scale scan angle by [n]  
-itranslate_scan_angle [n]          : translate input scan angle by [n]  
-keep_scan_angle [m] [n]            : keep points with scan angle between [m] and [n]  
-keep_scan_angle_between [m] [n]    : keep points with scan angle between [m] and [n]  
-scale_scan_angle [n]               : scale scan angle by [n]  
-set_scan_angle [n]                 : set scan angle to [n]  
-translate_scan_angle [n]           : translate scan angle by [n]  
-translate_then_scale_scan_angle [m] [n]: translate scan angle by [m] and scale by [n]  

### Tiles
-keep_tile [x] [y] [size] : keep tile at lower-left [x] [y] with size [s]  

### Waveform packet
-drop_wavepacket [n]     : drop points with wavepacket value of [n]  
-flip_waveform_direction : flip the waveform direction in the waveform VLR  
-keep_wavepacket [n]     : keep points with wavepacket value of [n]  

### Logical
-filter_and         : boolean AND combination of last 2 filters  
-filter_or          : boolean OR combination of last 2 filters  
-filtered_transform : do the transformation only on points of the current filter  

### Input
-i [fnp]        : input file or input file mask [fnp] (e.g. *.laz;fo?.la?;esri.shp,...)  
-io_ibuffer [n] : use read-input-buffer of size [n] bytes  
-iparse [xyz]   : define fields [xyz] for text input parser  
-ipts           : input as PTS (plain text lidar source), store header in VLR  
-iptx           : input as PTX (plain text extended lidar data), store header in VLR  
-iptx_transform : use PTX file header to transform point data  
-iskip [n]      : skip [n] lines at the beginning of the text input  
-itxt           : expect input as text file  
-lof [fnf]      : use input out of a list of files [fnf]  
-unique         : remove duplicate files in a -lof list  
-merged         : merge input files  
-buffered [n]   : use on-the-fly buffering of size [n] for tiles without implicit buffer  
-stdin          : pipe from stdin  

### Output
-do_not_populate : do not populate header on output  
-pipe_on         : write output to command pipe, see also -std_in  
-populate        : populate header on output  
-temp_files [n]  : set base file name [n] for temp files (example: E:\tmp)  

### parse
The '-parse [xyz]' flag specifies how to interpret each line of the ASCII file.
For example, 'tsxyzssa' means that the first number is the gpstime, the next
number should be skipped, the next three numbers are the x, y, and z coordinate,
the next two should be skipped, and the next number is the scan angle.

The other supported entries are:  
  x : [x] coordinate  
  y : [y] coordinate  
  z : [z] coordinate  
  t : gps [t]ime  
  R : RGB [R]ed channel  
  G : RGB [G]reen channel  
  B : RGB [B]lue channel  
  I : N[I]R channel of LAS 1.4 point type 8  
  s : [s]kip a string or a number that we don't care about  
  i : [i]ntensity  
  a : scan [a]ngle  
  n : [n]umber of returns of that given pulse  
  r : number of [r]eturn  
  h : with[h]eld flag  
  k : [k]eypoint flag  
  g : synthetic fla[g]  
  o : [o]verlap flag of LAS 1.4 point types 6, 7, 8  
  l : scanner channe[l] of LAS 1.4 point types 6, 7, 8  
  E : terrasolid [E]hco Encoding  
  c : [c]lassification. If extended classes are used: Use o,l or I to force 1.4 format.  
  u : [u]ser data  
  p : [p]oint source ID  
  e : [e]dge of flight line flag  
  d : [d]irection of scan flag  
  0-9 : additional attributes described as extra bytes (0 through 9)  
  (13) : additional attributes described as extra bytes (10 and up)  
  H : a hexadecimal string encoding the RGB color  
  J : a hexadecimal string encoding the intensity  

## Licensing

This tool is free to use.

## Support

1. We invite you to join our LAStools Google Group (http://groups.google.com/group/lastools/).
   If you are looking for information about a specific tool, enter the tool name in the search 
   function and you'll find all discussions related to the respective tool. 
2. Customer Support Page: https://rapidlasso.de/customer-support/.  
3. Download LAStools: https://rapidlasso.de/downloads/.  
4. Changelog: https://rapidlasso.de/changelog/.  


If you want to send us feedback or have questions that are not answered in the resources above, 
please email to info@rapidlasso.de.
