[Liblas-devel] Vertical Datum Conversion (Follow Up: Works fine with new liblas release)

[Ibraheem Ali]

Dear All,

I have downloaded the new release of "libLAS (libLAS 1.6.0b2)" from
"OSGeo4W" and run the vertical datum conversion command as follow:

las2las gal_000052.las --a_srs EPSG:32615 --t_srs EPSG:32615+5703

which basically assign (wgs84, UTM15) coordinate system to the original file
( --a_srs EPSG:32615 ), then transform the vertical datum to NAVD 88 (
--t_srs EPSG:32615+5703).

It worked great, thanks for the great effort.

I have also compared the result with the results from V-datum and they match
to the second decimal place very nicely.(sample calcs. included in this
e-mail).

Thank you very much,

With best regards,
Ibraheem



Below some sample lines from the original file, and the results from liblas,
and V-datum

Original file (WGS 84 UTM15, ellipsoidal height):

293999.95 3219406.51 -25.55
293999.9 3219406.56 -25.53
293999.77 3219406.67 -25.53
293999.72 3219406.71 -25.53
293999.71 3219406.72 -25.51

Liblas Conversion Result  (WGS 84 UTM15, NAVD 88)::

293999.95 3219406.51 0.94
293999.9 3219406.56 0.96
293999.77 3219406.67 0.96
293999.72 3219406.71 0.96
293999.71 3219406.72 0.98

V-Datum Conversion Result (WGS 84 UTM15, NAVD 88):

293999.95 3219406.51 0.9364
293999.9 3219406.56 0.9564
293999.77 3219406.67 0.9564
293999.72 3219406.71 0.9564
293999.71 3219406.72 0.9764
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