Adding an option to gdal_translate to preserve selected metadata domains (for example when changing data types)

[chuck1987]

What is the bug?

When I am translating a NITF file to NITF file I except the TRE information to be maintained.
It was noticed then anytime a run this translation I will lose my TRE information if I specify a -ot flag.

Even if I translate the NITF file to the same -ot of the original, the TRE information is still removed. If I specify no -ot flag the TRE information is maintained.

Steps to reproduce the issue

.\gdal_translate.exe .\input.ntf .\output.ntf -co IC=C8 -co JPEG2000_DRIVER=JP2OpenJPEG -ot Byte -> TRE information lost

.\gdal_translate.exe .\input.ntf .\out.ntf -co IC=C8 -co JPEG2000_DRIVER=JP2OpenJPEG -> TRE information maintained

Versions and provenance

Windows/Linux
GDAL 3.10

Additional context

No response

[rouault]

Changing the output data type might invalidate metadata.
When you just do direct NITF -> NITF without options (but driver creation options), the NITF driver is able to retrieve information directly from the source NITF dataset.
When you use -ot, gdal_translate uses internally a VRT dataset, and out of caution doesn't preserve metadata, but a few safe metadata domains. You must keep in mind that gdal_translate is a generic tool that has no particular knowledge of NITF specificities.
For your use case, for the time being, you'd better use the Python/C++ API and manually se the metadata
Perhaps gdal_translate could have a new switch where the user could specify which metadata domains to preserve or all

[chuck1987]

I figured it had something to do with that, but yes the gdal_translate switch would be a nice addition.
Currently using the TRE creation options to pass in all the original TRE information to the gdal_translate call as a possible work around.