Convert folder to .db

I have a map that I created using the 'old' oruxmaps settings in mobac that I would like to transfer to my phone. Unfortunately one of the folders has too many image tiles.

Is there a way of converting this folder of images (over 25,000 of them) into a .db image database. I have the original .xml file with coordinates of the map corners, but can't find a way of doing the conversion.