Re: [LAStools] full-waveform file format
172 views
Skip to first unread message
Martin Isenburg
Jul 27, 2017, 4:00:25 PM7/27/17
to LAStools - efficient command line tools for LIDAR processing, PulseWaves - no pulse left behind
Hello Dong,
If all your scanners are RIEGL then this is an interesting alternative to PulseWaves. In fact we took a lot of ideas from that format when designing PulseWaves and it there is a straight forward mapping from a pair of two files *.lgc/*.lwf to a pair of two files *.pls/*.wvs. See for example this pulseinfo report for a a pair of two files *.lgc/*.lwf:
A better discussion forum for this is http://pulsewaves.org. You already find some info there:
The full waveform format consisting of a pair of two files *.lgc/*.lwf is very similar to the PulseWaves format but not quite as fexible. It is a format that was created by GeoLas Consulting with the primary goal to map the full waveform content from the SDF files produced by the Q-Line of RIEGL scanners into an geo-referenced and easier to parse binary format. The software sold by GeoLas Consulting takes SDF files, trajectories, and more as input and generates a pair of two files *.lgc/*.lwf as output. In particular when the SDF file contains a segment of the waveform that was sampled by the less sensitive 8 bit receiver (i.e. a high channel segment) then their software creates a *single* waveform segment that is sampled with 16 bits from the 8 bit low channel segment(s) and the 8 bit high channel segment.
E:\projects\pulsetools\bin>pulseinfo -i 130603_234218_L01.lgc
reporting all PULSE header entries:
file signature: 'PulseWavesPulse'
global parameters: 0
file source ID: 0
project ID GUID data 1-4: 00000000-0000-0000-0000-000000000000
system identifier: 'created by PULSEreaderGCW'
generating software: 'PulseWaves 0.3 r11 (150708) by rapidlasso'
file creation day/year: 333/2012
version major.minor: 0.3
header size: 352
offset to pulse data: 1488
number of pulses: 494738
pulse format: 0
pulse attributes: 0
pulse size: 48
pulse compression: 0
number vlrs: 3
number avlrs: 0
scale factor and offset t: 1e-006 1000000000
min max T: 0 0
scale factor x y z: 0.01 0.01 0.01
offset x y z: 52700000 8500000 0
min x y z: 52678586.58 8540391.86 -4.01
max x y z: 52678960.86 8540537.42 32.13
variable length header record 1 of 3:
reserved 0
user ID 'PulseWaves_Spec'
record ID 100001
length after header 248
description 'PulseWaves 0.3 r11 (150708) by rapidlasso'
PULSEscanner 1
instrument: ''
serial: ''
wave_length: 1064 [nanometer]
outgoing_pulse_width: 10 [nanoseconds]
scan_pattern: 0 ('undefined')
number_of_mirror_facets: 0
scan_frequency: 0 [hertz]
scan_angle_min: 0 [degree]
scan_angle_max: 0 [degree]
pulse_frequency: 0 [kilohertz]
beam_diameter_at_exit_aperture: 0 [millimeters]
beam_divergence: 0 [milliradians]
minimal_range: 0 [meters]
maximal_range: 0 [meters]
description: ''
variable length header record 2 of 3:
reserved 0
user ID 'PulseWaves_Spec'
record ID 200001
length after header 300
description 'PulseWaves 0.3 r11 (150708) by rapidlasso'
PULSEdescriptor 1
optical_center_to_anchor_point: 0x0 ('coincide')
number_of_extra_waves_bytes: 0
number_of_samplings: 2
sample_units: 1 [nanoseconds]
scanner_index: 1
compression: 0
description: 'GeoLas GCW pulse (8 bit)'
sampling[0]
type: 1 ('outgoing')
channel: 0
bits_for_duration_from_anchor: 0
scale_for_duration_from_anchor: 1
offset_for_duration_from_anchor: 0
bits_for_number_of_segments: 0
bits_for_number_of_samples: 16
number_of_segments: 1
number_of_samples: 0
bits_per_sample: 8
lookup_table_index: 0 ('undefined')
sample_units: 1.0 [nanoseconds]
compression: 0
description: 'outgoing at 8 bits'
sampling[1]
type: 2 ('returning')
channel: 0
bits_for_duration_from_anchor: 16
scale_for_duration_from_anchor: 1
offset_for_duration_from_anchor: 0
bits_for_number_of_segments: 0
bits_for_number_of_samples: 16
number_of_segments: 1
number_of_samples: 0
bits_per_sample: 8
lookup_table_index: 0 ('undefined')
sample_units: 1.0 [nanoseconds]
compression: 0
description: 'returning at 8 bits'
variable length header record 3 of 3:
reserved 0
user ID 'PulseWaves_Spec'
record ID 200002
length after header 300
description 'PulseWaves 0.3 r11 (150708) by rapidlasso'
PULSEdescriptor 2
optical_center_to_anchor_point: 0x0 ('coincide')
number_of_extra_waves_bytes: 0
number_of_samplings: 2
sample_units: 1 [nanoseconds]
scanner_index: 1
compression: 0
description: 'GeoLas GCW pulse (16 bit)'
sampling[0]
type: 1 ('outgoing')
channel: 0
bits_for_duration_from_anchor: 0
scale_for_duration_from_anchor: 1
offset_for_duration_from_anchor: 0
bits_for_number_of_segments: 0
bits_for_number_of_samples: 16
number_of_segments: 1
number_of_samples: 0
bits_per_sample: 8
lookup_table_index: 0 ('undefined')
sample_units: 1.0 [nanoseconds]
compression: 0
description: 'outgoing at 8 bits'
sampling[1]
type: 2 ('returning')
channel: 0
bits_for_duration_from_anchor: 16
scale_for_duration_from_anchor: 1
offset_for_duration_from_anchor: 0
bits_for_number_of_segments: 0
bits_for_number_of_samples: 16
number_of_segments: 1
number_of_samples: 0
bits_per_sample: 16
lookup_table_index: 0 ('undefined')
sample_units: 1.0 [nanoseconds]
compression: 0
description: 'returning at 16 bits'
reporting minimum and maximum for all PULSE record entries ...
ERROR: reading wfi
T 0 0
offset 0 104715818
anchor_X -2128591 -2118533
anchor_Y 4034290 4052961
anchor_Z 30071 33101
target_X -2133843 -2112549
target_Y 4034717 4054933
target_Z 15127 19652
first_returning_sample 240 2356
last_returning_sample 2065 2485
descriptor_index 1 2
reserved 0 0
edge_of_scan_line 0 0
scan_direction 0 0
mirror_facet 0 0
intensity 0 0
classification 0 0
re-reporting PULSE header entries populated during read pass:
min x y z 52678586.57 8540352.04 -32.17
max x y z 52678964.87 8540576.66 294.10
And attached a screenshot from running
E:\projects\pulsetools\bin>pulseview -i 130603_234218_L01.lgc
with the end-of-recording sample of the digitized part from each pulse once colored by elevation and once by pulsedescriptor (yellow = 8 bit waveform sampling, orange = 16 bit waveform sampling).
On Jul 23, 2017 12:07 PM, "dong chen" <chendon...@gmail.com> wrote:
Dear Martin,--What are differences between two types of full-waveform file format namely *lgc/*lwf and *.pls /*.wvs?Why do we use these two kinds of full-waveform format files rather than one of them? I am looking forward to you reply thanks.With my best regards,Dong Chen
Download LAStools at
http://lastools.org
http://rapidlasso.com
Be social with LAStools at
http://facebook.com/LAStools
http://twitter.com/LAStools
http://linkedin.com/groups/LAStools-4408378
Manage your settings at
http://groups.google.com/group/lastools/subscribe
Reply all
Reply to author
Forward
0 new messages