Skip to main content

Hi,

I have two raster files, DEM_epsg25831_orthoHeights.tif and GEOID_epsg4326.tif, and I have to convert from orthometric heights of raster DEM to ellipsoidal ones. I am using CsmapReprojector 3] with FME Workbench 2019.1 but I have problems with vertical adjustment.

I always get this error:

CsmapReprojector: Reproject: Could not reproject the geometry of the preceding feature: 

Program Terminating

Translation FAILED.

  

 

These are the steps that I follow for vertical adjustment:

 

1) I have converted DEM_epsg25831_orthoHeights.tif into dtm_epsg25831_orto.asc (Esri Ascii GRID), because CsmapReprojector can only reproject raster files in 2D (that is, with Ignore heights and leave them unchanged) a1].

 

This is the content of dtm_epsg25831_orto.asc (sample data for test),

NCOLS          3

NROWS          3

XLLCENTER    398955.000000000

YLLCENTER    4624395.00000000

CELLSIZE    5.00000000000000

NODATA_VALUE    -9999

252.71 252.38 251.94

252.97 252.63 252.26

253.23 252.89 252.55

 

 

2) I also, I have converted GEOID_epsg4326.tif to EGM96 GRD format using convert-ngrid-to-grd.fmw M2].

 

3) F‌inally, I have created a .gdc file and I have copied binary ._96 file with .grd file n2, Update note]

 

I have tried CsmapReprojector with 2D reprojection (epsg2581 -> epsg4326) and works perfect, the problem is with vertical adjustment.

 

I am wondering if there is something else I'm forgetting to do?

Thank you

 

;1] http://docs.safe.com/fme/html/FME_Desktop_Documentation/FME_Transformers/Transformers/csmapreprojector.htm

f2] https://community.safe.com/s/article/creating-vertical-adjustment-grid-files-for-use-wi

v3] https://community.safe.com/s/article/which-transformer-do-i-use-to-do-3d-reprojection-v

FME interprets the FME ASCII grid also as a raster - so I suspect this could be where the problem is. You can instead convert to a PointCloud and then apply the vertical adjustment. go back to a raster (NmericRasteriser)

https://community.safe.com/s/question/0D54Q000080hHnySAE/how-can-i-change-the-vertical-datum-vertically-reproject-in-a-raster-dem

 

Here's an example workflow

 


FME interprets the FME ASCII grid also as a raster - so I suspect this could be where the problem is. You can instead convert to a PointCloud and then apply the vertical adjustment. go back to a raster (NmericRasteriser)

https://community.safe.com/s/question/0D54Q000080hHnySAE/how-can-i-change-the-vertical-datum-vertically-reproject-in-a-raster-dem

 

Here's an example workflow

 

Thank you @virtualcitymatt​ , your suggestion works perfect !


Reply