[gdal-dev] gdalwarp on a separate RPC model

[Even Rouault]

Le lundi 15 juin 2015 20:18:02, Yi Dong a écrit :
> Dear List,
> 
> I have a question about recitify satellite images that has RPC camera
> using gdalwarp.  I know gdalwarp can be used for this task, with using
> RPC metadata (either packed inside the NITF or stored inside RPB files)
> Normally, the image folder shall contain following files
> input.ntf
> input.rpb
> input.imd
> etc...
> The command I used for this is
> gdalwarp -rpc input.ntf -to RPC_HEIGHT=200 rectified.tif
> 
> Now I performed some geo-correction on the satellite image and generate
> a corrected RPC model (with imporved offset values) and I store this
> correct RPC camera in 'correct.rpb'.  Now I am trying to use this
> 'correct.rpb' to recitify the image
> I tried
> gdalwarp -rpc input.ntf correct.rpb -to RPC_HEIGHT=200
> recitify_corrected.tif
> but it failed with following error
> ERROR 4: 'correct.rpb' not recognized as a supported file format
> 
> Then I tried to overwrite the 'input.rpb' in the image folder with my
> 'corrected.rpb', run 'gdalwarp -rpc input.ntf -to RPC_HEIGHT=200
> rectified.tif' again but I got exactly same results as I used the
> original RPC model.  I guess that might be because gdalwarp used RPC
> parameter that was packed inside NITF image itself, instead of getting
> them from rpb files ?
> 
> So Is there other way to use my corrected RPC model in gdal, like
> gdalwarp, gdal_transform, etc.?
> Also, gdaltransform doesn't not accept RPB files either.  It only
> recognizes GDAL dataset, i.e. vrt file.  Therefore I need to generate
> vrt file from my RPB.  Is there any vrt example for RPC camera that I
> can follow?

Ian,

I'd suggesting gdal_translate'ing your input.ntf into a VRT, and replace the 
values in the "VRT" metadata domain with your own values. Then you can run 
gdalwarp on this VRT file

Even

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