[Liblas-devel] Re: GetProj4() string and NAD83

[Adam Stylinski]

On Tue, Jan 10, 2012 at 1:25 PM, Howard Butler <hobu.inc at gmail.com> wrote:

> and LAStools now does vertical datum transformations too? If so, even more
> reason to not use libLAS :)
>
> On Jan 10, 2012, at 12:10 PM, Martin Isenburg wrote:
>
> > Hi,
> >
> > when debugging GDAL it may help to look at what LASlib's
> > geoprojectionconverter does, which finds that the file
> > "IowaDNR-CloudPeakSoft-1.0-UTM15N.las" has correct GeoTIFFs . When I
> > create an intensity grid with
> >
> > lasgrid -i IowaDNR-CloudPeakSoft-1.0-UTM15N.las -intensity -opng -step 3
> >
> > the generated intensity raster is automatically geo-referenced and a
> > corresponding KML file is generated that places the PNG onto Google
> > Earth at the exact right spot as you can see here:
> >
> > http://lastools.org/download/data/IowaDNR-CloudPeakSoft-1.0-UTM15N.kmz
> >
> > Cheers,
> >
> > Martin @lastools
> >
> > PS: below is the report of lasinfo -i
> IowaDNR-CloudPeakSoft-1.0-UTM15N.las
> >
> > reporting all LAS header entries:
> >  file signature:            'LASF'
> >  file source ID:            0
> >  global_encoding:           0
> >  project ID GUID data 1-4:  0 0 0 ''
> >  version major.minor:       1.0
> >  system identifier:         ''
> >  generating software:       'CPS/RTW LAS Lib v1.08'
> >  file creation day/year:    0/0
> >  header size                227
> >  offset to point data       639
> >  number var. length records 3
> >  point data format          1
> >  point data record length   28
> >  number of point records    5847380
> >  number of points by return 2920986 2926394 0 0 0
> >  scale factor x y z         0.001 0.001 0.001
> >  offset x y z               0 4000000 0
> >  min x y z                  614000.000 4791999.999 311.676
> >  max x y z                  615999.990 4793999.989 398.959
> > variable length header record 1 of 3:
> >  reserved             43707
> >  user ID              'LASF_Projection'
> >  record ID            34735
> >  length after header  88
> >  description          'Projection Info'
> >    GeoKeyDirectoryTag version 1.1.0 number of keys 10
> >      key 1024 tiff_tag_location 0 count 1 value_offset 1 -
> > GTModelTypeGeoKey: ModelTypeProjected
> >      key 1026 tiff_tag_location 34737 count 13 value_offset 0 -
> > GTCitationGeoKey: UTM zone 15N
> >      key 2050 tiff_tag_location 0 count 1 value_offset 6269 -
> > GeogGeodeticDatumGeoKey: Datum_North_American_Datum_1983
> >      key 2056 tiff_tag_location 0 count 1 value_offset 7019 -
> > GeogEllipsoidGeoKey: Ellipse_GRS_1980
> >      key 3072 tiff_tag_location 0 count 1 value_offset 26915 -
> > ProjectedCSTypeGeoKey: PCS_NAD83_UTM_zone_15N
> >      key 3075 tiff_tag_location 0 count 1 value_offset 1 -
> > ProjCoordTransGeoKey: CT_TransverseMercator
> >      key 3076 tiff_tag_location 0 count 1 value_offset 9001 -
> > ProjLinearUnitsGeoKey: Linear_Meter
> >      key 4096 tiff_tag_location 0 count 1 value_offset 5103 -
> > VerticalCSTypeGeoKey: VertCS_North_American_Vertical_Datum_1988
> >      key 4097 tiff_tag_location 34737 count 19 value_offset 13 -
> > VerticalCitationGeoKey: GEOID 2003 Applied
> >      key 4099 tiff_tag_location 0 count 1 value_offset 9001 -
> > VerticalUnitsGeoKey: Linear_Meter
> > variable length header record 2 of 3:
> >  reserved             43707
> >  user ID              'LASF_Projection'
> >  record ID            34737
> >  length after header  32
> >  description          'Projection Info'
> >    GeoAsciiParamsTag (number of characters 32)
> >      UTM zone 15N GEOID 2003 Applied
> > variable length header record 3 of 3:
> >  reserved             43707
> >  user ID              'CloudPeakSoft'
> >  record ID            0
> >  length after header  128
> >  description          'CPSInfo'
> > the header is followed by 2 user-defined bytes
> > reporting minimum and maximum for all LAS point record entries ...
> >  x 614000000 615999990
> >  y 791999999 793999989
> >  z 311676 398959
> >  intensity 1 3240
> >  edge_of_flight_line 0 0
> >  scan_direction_flag 0 0
> >  number_of_returns_of_given_pulse 2 2
> >  return_number 1 2
> >  classification 1 12
> >  scan_angle_rank 0 0
> >  user_data 0 0
> >  point_source_ID 14 18
> >  gps_time 597987.305116 600731.680834
> > overview over number of returns of given pulse: 0 5847380 0 0 0 0 0
> > histogram of classification of points:
> >  2762810 Unclassified (1)
> >  2156929 Ground (2)
> >     6318 Low Point (noise) (7)
> >   921323 Overlap Points (12)
>
> _______________________________________________
> Liblas-devel mailing list
> Liblas-devel at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/liblas-devel
>
>
I should probably mention that my proj.4 is built with datum grids as well.
 Liblas is built with GDAL and geotiff as well.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.osgeo.org/pipermail/liblas-devel/attachments/20120110/ff1d889c/attachment-0001.html