OruxMaps supports tfw, for jgw just rename extension from jgw to tfw. The batch conversion tool has not yet support for tfw/jgw.
If the map is of unsupported datum and/or projection, or you want to use batch tool.
For jpeg-maps: rename the extensions, jpeg to jpg and tfw to jgw, for OziExplorer to be able to find the files, if needed.
jpg maps uses jgw as calibration file, tiff/bmp uses tfw.
Import the converted file(s) as DRG maps in OziExplorer. Ozi will create map-files for each jpg-file.
Convert all maps using OruxMapsDesktop, use projection UTM. To be able to do this in a batch (while so many map tiles are created) do as follow:
add “RT 90|RT90Swedish” to the file Ozi2Orux.txt in the OruxMapsDesktop install directory if the map uses RT90 datum.
if needed: in all created map-files, change “(SG) Swedish Grid” to “(UTM) Universal Transverse Mercator”, this because the batch converter in OruxMapsDesktop currently do not support Swedish grid.