go get github.com/bodgit/megasd/...

To import an existing database generated by the C# tool:

megasd import /path/to/db.xml

(This will need the XML file and the original PNG image files.)

You can then scan your Micro SD card and generate the metadata:

megasd scan /Volumes/MEGADRIVE

The tool uses a small SQLite database, the location of which defaults to $PWD/megasd.db. You can pass a --db flag or set the environment variable $MEGASD_DB to put this file somewhere else.