Kontinuation commented on issue #941:
URL: https://github.com/apache/sedona/issues/941#issuecomment-1710981065

   `RS_FromGeoTiff` reads CRS metadata from the GeoTiff file, and the resulting 
raster value will have that CRS property. You can retrieve the EPSG code of the 
CRS using `RS_SRID` (if it has one).
   
   `RS_FromGeoTiff` is using GeoTools GeoTiff reader under the hood. However, 
I've not found any documentation describing the limitation of GeoTools GeoTiff 
reader. The limitation I am aware of is that it does not support user defined 
Model CRS type (GTModelTypeGeoKey = 32767, see [Requirements Class 
GTModelTypeGeoKey](https://docs.ogc.org/is/19-008r4/19-008r4.html#_requirements_class_gtmodeltypegeokey)).
   
   For vector data, the default SRID is 0, which indicates that the geometry 
does not have a defined CRS. `ST_GeomFromGeoJSON` does not support parsing the 
crs member in GeoJSON, and the resulting geometries always have SRID = 0.
   
   SRID is the EPSG code of coordinate reference systems. The CRS is forced to 
easting/northing or lon/lat axis order since 
https://github.com/apache/sedona/pull/963, which will be released with 1.5.0. 
For any released versions of Apache Sedona, the CRS uses the original axis 
order defined by EPSG.
   
   I think explicitly documenting the behaviors related to CRS would be 
beneficial. As we integrate raster support into Apache Sedona, this aspect is 
gaining increasing significance.


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