Create Basecamp installer .exe from mkgmap generated IMG

I swear I’ve spent hours and hours searching the internet for the answer.

I have downloaded a Garmin IMG that was originally created from OSM data.
I’ll all it “downloaded_freedonia_osm.img” here.
It works if I copy it to nuvi:/Internal Storage/Map. It works in Basecamp if I connect the Nuvi to my computer. It works with Basecamp if copy it to a connected thumb drive. E.g. e:/Garmin/Maps/downloaded_freedonia_osm.img.

But I want to install it on the PC so that I can use it with basecamp without a thumb drive or the Nuvi connected to the computer.

I do:
java -ea -Xmx1200m -jar mkgmap.jar

Then I run makensis.

The resulting .exe is not right. There is no main map in it. There appears to be the overview map.
I look in the osmmap.nsi and I see.
; Files to be installed
SetOutPath “$INSTDIR”
File “${MAPNAME}.img” (osmmap.img)
File “${MAPNAME}.tdb”

I think osmmap.img is an overview map. There seems to be is no main map listed.

When I try a simple test starting with OSM data, not a OSM Garmin IMG, I get a “63240001.img” file. And there is an additional entry in the nsi for it.
File “63240001.img”

Why do I get a 63240001.img when starting from a .osm but not from a .img?

How do I make a Basecamp installable from a premade OSM Garmin IMG?


What’s the content of downloaded_freedonia_osm.img? Is is a single map tile or a gmapsupp file?
mkgmap cannot read the latter.
If it is a gmapsupp file you can copy it to a usb device into a \Garmin folder and try to open that in Basecamp. Or install it on a device and attach that device via USB before starting Basecamp. If that doesn’t work the map has a bit set which tells Basecamp to NOT open this gmapsupp. If the file downloaded_freedonia_osm.img is a gmapsupp that was created with mkgmap it should be possible to split it with e.g. gmaptool and produce either the nsis installer or the gmapi format. You probably also want the --index option for this.

Thanks for the tips. Gmaptool did the trick for me. Using the Split tab I can take in the equivalent of a gmapsupp.img and make something that can be installed on the PC for Basecamp.

(I didn’t want to have to copy the gmapsupp.img to my Nuvi or usb stick and then have to have that connected to the computer in order to use it on Basecamp.)



You can also use osm combiner to do this