Map RGB to intensity (or vice versa)

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Blake Lytle

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Oct 24, 2018, 6:12:02 PM10/24/18

to LAStools - efficient tools for LiDAR processing

I'm working with some point clouds I created using our FARO terrestrial scanner, some with RGB color and some without. Those without RGB seem to have the intensity mapped to RGB as that's how they display using RGB. Is there an easy way to map one attribute to the other with the LAStools?

Martin Isenburg

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Oct 24, 2018, 6:41:30 PM10/24/18

to last...@googlegroups.com

Hello,

if you look at the source code of lastransform.cpp (available on github and in the LASlib subfolder) you see the supported transforms. Also below is a way to list them. It seems you need ' -copy_RGB_into_intensity'. Do you also need '-copy_intensity_into_RGB'?

Martin

C:\software\LAStools\bin> las2las -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

-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

-copy_intensity_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

-copy_RGB_into_intensity

-copy_NIR_into_intensity

-copy_attribute_into_intensity 0

-bin_gps_time_into_intensity 0.5

Transform scan_angle.

-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

-set_number_of_returns 2

-set_number_of_returns 15

-change_number_of_returns_from_to 0 2

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

-copy_attribute_into_user_data 1

Modify the point source ID.

-set_point_source 500

-change_point_source_from_to 1023 1024

-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

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

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 mar...@rapidlasso.com) version 181001

usage:

las2las -i *.las -utm 13N

las2las -i *.laz -first_only -olaz

las2las -i *.las -drop_return 4 5 -olaz

las2las -latlong -target_utm 12T -i in.las -o out.las

las2las -i in.laz -target_epsg 2972 -o out.laz

las2las -point_type 0 -lof file_list.txt -merged -o out.las

las2las -remove_vlr 2 -scale_rgb_up -i in.las -o out.las

las2las -i in.las -keep_xy 630000 4834500 630500 4835000 -keep_z 10 100 -o out.las

las2las -i in.txt -iparse xyzit -keep_circle 630200 4834750 100 -oparse xyzit -o out.txt

las2las -i in.las -remove_padding -keep_scan_angle -15 15 -o out.las

las2las -i in.las -rescale 0.01 0.01 0.01 -reoffset 0 300000 0 -o out.las

las2las -i in.las -set_version 1.2 -keep_gpstime 46.5 47.5 -o out.las

las2las -i in.las -drop_intensity_below 10 -olaz -stdout > out.laz

las2las -i in.las -last_only -drop_gpstime_below 46.75 -otxt -oparse xyzt -stdout > out.txt

las2las -i in.las -remove_all_vlrs -keep_class 2 3 4 -olas -stdout > out.las

las2las -h

On Thu, Oct 25, 2018 at 12:12 AM Blake Lytle <bal...@g.clemson.edu> wrote:

I'm working with some point clouds I created using our FARO terrestrial scanner, some with RGB color and some without. Those without RGB seem to have the intensity mapped to RGB as that's how they display using RGB. Is there an easy way to map one attribute to the other with the LAStools?

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J. Thaddeus Eldredge

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Oct 24, 2018, 6:42:21 PM10/24/18

to last...@googlegroups.com

So the FARO export gives you an option to export both color and b&w. Otherwise color includes the RGB and no I, and uncolored has the I. Select the option and you get RGBI (or whatever order these values are assigned).

On Wed, Oct 24, 2018, 6:11 PM Blake Lytle <bal...@g.clemson.edu> wrote:

I'm working with some point clouds I created using our FARO terrestrial scanner, some with RGB color and some without. Those without RGB seem to have the intensity mapped to RGB as that's how they display using RGB. Is there an easy way to map one attribute to the other with the LAStools?