Imf_copy and EXR format.

If you try using flags such as –r or –p you will be prompted with
MAIN 0.0  warn : imf_copy: mipmap pyramid levels can be created for .map files only, ignoring
MAIN 0.0  warn : imf_copy: tiles can be created for .map files only, ignoring

To create tillable images using the imf_copy command along with the –r flag , however this flag dosnt work with EXR format. You need to use map format as your output
order to properly create .exr rip-map or mip-map, you need to use exrmaketiled.exe which comes with openEXR distribution.