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NLeSC / PattyData

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Add spacial reference information to las file headers #4

Closed Maartenvm closed 10 years ago

Maartenvm commented 10 years ago

Currently, the las file headers look like: 

---------------------------------------------------------
  Header Summary
---------------------------------------------------------

  Version:                     1.2
  Source ID:                   0
  Reserved:                    1
  Project ID/GUID:             '00000000-0000-0000-0000-000000000000'
  System ID:                   ''
  Generating Software:         'TerraScan'
  File Creation Day/Year:      15/2014
  Header Byte Size             227
  Data Offset:                 229
  Header Padding:              2
  Number Var. Length Records:  None
  Point Data Format:           3
  Number of Point Records:     1765844
  Compressed:                  False
  Number of Points by Return:  1765844 0 0 0 0
  Scale Factor X Y Z:          0.001 0.001 0.001
  Offset X Y Z:                -0.000 4000000.000 -0.000
  Min X Y Z:                   296889.853 4632264.826 121.496
  Max X Y Z:                   296989.862 4632364.823 138.196
  Spatial Reference:           None

The Spacial Reference field is empty, and we need this information to determine the correct transformations required for georeferencing.

We believe the correct spatial reference information can be found in the footprints.

oscarmartinezrubi commented 10 years ago

The spatial reference is -> SRID = 32633

Maartenvm commented 10 years ago

Created an issue for the Analysis team to add this spatial reference information to the aligned las output data as well... See: https://github.com/NLeSC/PattyAnalytics/issues/2

elboyran commented 10 years ago

Oscar provided alternative solution- the reference systems are specified in a JSOn file together with the Point cloud.