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I used R to batch process object based image segmentation on some geoTIFF files using rgdal to communicate with SAGA GIS. I got the resulting shapefiles, all with the following properties:

Projection Undefined Coordinate System West -0.5 East 7999.5 West-East 8000 South -0.5 North 3999.5 South-North 4000 Type Polygon Vertex Type X, Y

For each individual file, I got the following warnings:

15:13:13: Warning: Unknown field with tag 33550 (0x830e) encountered (in module "TIFFReadDirectory") 15:13:13: Warning: Unknown field with tag 33922 (0x8482) encountered (in module "TIFFReadDirectory") 15:13:13: Warning: Unknown field with tag 34735 (0x87af) encountered (in module "TIFFReadDirectory") 15:13:13: Warning: Unknown field with tag 33550 (0x830e) encountered (in module "TIFFReadDirectory") 15:13:13: Warning: Unknown field with tag 33922 (0x8482) encountered (in module "TIFFReadDirectory") 15:13:13: Warning: Unknown field with tag 34735 (0x87af) encountered (in module "TIFFReadDirectory")

The shapefiles that were created are fine, expect that when I attempt to project them in any given coordinate system, it projects incorrectly. I am not sure what the standard or default projection is in SAGA, as it appears that when the TIFFs were imported, they lost their spatial reference/coordinate system. I have tried defining and projecting a coordinate system, but when I change the extent of the grid file, I get an empty map.

I would like to copy the coordinate system and extent of the TIFF file and "assign" or coerce it to its respective shapefile in SAGA. The desired attributes are as follows:

Projection Projected Coordinate System [EPSG 2006]: St.Lucia1955/BritishWestIndiesGrid [+proj=tmerc +lat_0=0 +lon_0=-62 +k=0.9995000000000001 +x_0=400000 +y_0=0 +ellps=clrk80 +towgs84=-149,128,296,0,0,0,0 +units=m +no_defs ] West 499993.1 East 502004.5 West-East 2011.400000000023 South 1522994.7 North 1524000.4 South-North 1005.6999999999534 Cell Size 8.9

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  • Your "errors" are just warnings, though they may indicate incomplete support for the geoTIFF source image. Please Edit the question to focus on one GIS package, since three is two too many to meet the "One question per Question" policy, as described in the Tour.
    – Vince
    Jun 15, 2017 at 11:09
  • It looks like the original raster is not georeferenced, or the georeferencing was not used when converting to shapefiles. If you can't fix the export, you'll have to use the spatial adjustment tool bar (if in ArcMap) to force the data to a known coordinate system.
    – mkennedy
    Jun 15, 2017 at 20:33

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