sample data wanted: Albers CONUS / Albers Equal Area Conic

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Martin Isenburg

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May 15, 2015, 3:54:21 PM5/15/15
to LAStools - efficient command line tools for LIDAR processing
Hello,

does someone have sample LAS / LAZ data in a Albers CONUS / Albers Equal Area Conic projection such as one of those?


I would need a small tile for testing.

Thanks!

Martin @rapidlasso

Heidemann, Hans

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May 29, 2015, 2:58:34 AM5/29/15
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5072

Karl

H. Karl Heidemann, GISP
Physical Scientist, Lidar Science
U.S. Geological Survey
Mundt Federal Building
47914 252nd Street
Sioux Falls, SD  57110

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WA_PierceCo_2010_w1987n2977.laz

Martin Isenburg

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May 29, 2015, 5:33:27 AM5/29/15
to LAStools - efficient command line tools for LIDAR processing
Hello,

thanks for the sample data. Not that interesting though (a bit of the water surface of commencement bay). But it the new EPSG codes (and the Albers Equal Area Conic projection) seem to work okay:

// using EPSG 5072 directly
las2dem -i WA_PierceCo_2010_w1987n2977.laz -last_only -hillshade -opng
lasinfo -i WA_PierceCo_2010_w1987n2977.laz -odix _info -otxt

// reproject to UTM
las2las -i WA_PierceCo_2010_w1987n2977.laz -target_utm auto -odix _utm -olaz 

// using reprojected UTM
las2dem -i WA_PierceCo_2010_w1987n2977_utm.laz -last_only -hillshade -opng
lasinfo -i WA_PierceCo_2010_w1987n2977_utm.laz -odix _info -otxt

Regards,

Martin @rapidlasso

PS: Looks like I need to make sure that when reprojection las2las will *delete* the then out-of-date LAStiling information from the LAS header ...
WA_PierceCo_2010_w1987n2977_info.txt
WA_PierceCo_2010_w1987n2977.kmz
WA_PierceCo_2010_w1987n2977_utm_info.txt

Martin Isenburg

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May 29, 2015, 6:00:18 AM5/29/15
to LAStools - efficient command line tools for LIDAR processing
Hello again.

offline Karl had send me a larger LAZ file with about half a million points that already has the ESPG code 5072 in its GeoTIFF tags.

las2dem -i EPSG-5072_Sample.laz -last_only -hillshade -opng

the resulting geo-referenced KML embedded PNG seems reasonably well aligned with Google Earth imagery (see attached pic). Nevertheless we use las2las to set (*only* set. this does not reproject) the EPSG key to 5072 via the GeoTIFF tags

las2las -i EPSG-5072_Sample.laz -epsg 5072 -odix _5072 -olaz

and look at the new GeoTIFF tags with lasinfo

lasinfo -i EPSG-5072_Sample_5072.laz

reporting all LAS header entries:
  file signature:             'LASF'
  file source ID:             0
  global_encoding:            0
  project ID GUID data 1-4:   905441C8-9857-4AB7-62A2-F970E8D1D7D2
  version major.minor:        1.2
  system identifier:          'LAStools (c) by rapidlasso GmbH'
  generating software:        'las2las (version 150516)'
  file creation day/year:     55/2012
  header size:                227
  offset to point data:       1085
  number var. length records: 2
  point data format:          1
  point data record length:   28
  number of point records:    448566
  number of points by return: 369493 72679 6196 198 0
  scale factor x y z:         0.01 0.01 0.01
  offset x y z:               0 0 0
  min x y z:                  2128000.00 2711000.00 28.21
  max x y z:                  2128568.03 2711760.39 87.18
variable length header record 1 of 2:
  reserved             43707
  user ID              'LASF_Projection'
  record ID            34735
  length after header  40
  description          'by LAStools of rapidlasso GmbH'
    GeoKeyDirectoryTag version 1.1.0 number of keys 4
      key 1024 tiff_tag_location 0 count 1 value_offset 1 - GTModelTypeGeoKey: ModelTypeProjected
      key 3072 tiff_tag_location 0 count 1 value_offset 5072 - ProjectedCSTypeGeoKey: NAD83(NSRS2007) / Conus Albers
      key 3076 tiff_tag_location 0 count 1 value_offset 9001 - ProjLinearUnitsGeoKey: Linear_Meter
      key 4099 tiff_tag_location 0 count 1 value_offset 9001 - VerticalUnitsGeoKey: Linear_Meter
variable length header record 2 of 2:
  reserved             43707
  user ID              'liblas'
  record ID            2112
  length after header  710
  description          'OGR variant of OpenGIS WKT SRS'
LASzip compression (version 2.3r0 c2 50000): POINT10 2 GPSTIME11 2
LAStiling (idx 9591, lvl 7, sub 0, bbox 2.065e+006 2.642e+006 2.193e+006 2.77e+006)
reporting minimum and maximum for all LAS point record entries ...
  X           212800000  212856803
  Y           271100000  271176039
  Z                2821       8718
  intensity           0        255
  return_number       1          4
  number_of_returns   1          4
  edge_of_flight_line 0          1
  scan_direction_flag 0          1
  classification      1         18
  scan_angle_rank    -3         23
  user_data         198        255
  point_source_ID   811        812
  gps_time -26285365.622809 -26284922.939496
WARNING: range violates GPS week time specified by global encoding bit 0
overview over number of returns of given pulse: 297200 132611 17965 790 0 0 0
histogram of classification of points:
          193899  unclassified (1)
           58853  ground (2)
             161  noise (7)
             332  road surface (11)
          159141  bridge deck (17)
           36180  Reserved for ASPRS Definition (18)

Regards,

Martin @rapidlasso
epsg_5072.png
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