Handling data with GCPs or RPCs

[rbudhu]

Hi: I am trying to use TiTiler for image data that does not have CRS information in the header, but does have ground control points and rational polynomial coefficients (example: a NITF converted to a COG). Could TiTiler be updated to use this information (rasterio support calculating transforms with GCP and RPC values)? Can such a capability be added to the feature roadmap? Thanks!

[vincentsarago]

Hi @rbudhu
could you check if you can open your file using rio_tiler.io.GCPCOGReader ?

from rio_tiler.io import GCPCOGReader

with GCPCOGReader("youfile") as cog:
    print(cog.info())

if this works, then you could create your own application as shown here https://developmentseed.org/titiler/examples/code/mini_cog_tiler/

but instead of using default COGReader use GCPCOGReader as the reader

cog = TilerFactory(reader=GCPCOGReader)

[rbudhu]

Awesome! Seems to work! Thanks!