#601135 navit can't read my garmin img file

Package:
navit
Source:
navit
Description:
Car navigation system with routing engine
Submitter:
Mouarfffff
Date:
2017-10-06 17:03:03 UTC
Severity:
normal
#601135#5
Date:
2010-10-23 17:20:34 UTC
From:
To:
Hello,

I have a problem when I load a img garmin file on navit.
I see abnormal caracteres and no map.

When I lanuch garmin from the command line, I can see this :

:garmin_obj.c:849:3|:Loading level:2 bits:19
:garmin_obj.c:886:1|:Error no objects found
:garmin.c:852:2|:Loaded 0 objects

Sometimes, navit doesn't response at all when i load this map.
It's work with OSM maps.

#601135#10
Date:
2010-10-24 09:28:14 UTC
From:
To:
Hi Mouarfffff,

Mouarfffff a écrit , Le 23/10/2010 19:20:

I knew I would eventually receive such a bug report :/

The reason is that I don't have any Garmin map to test the plugin with.

I'm not sure about what to do there. It may ends up by removing
libgarmin from squeeze if I can't find out what's going on.

Is is possible for you to send me a - not too heavy - Garmin file so I
could have a look at the problem?

Thanks,

_g.

#601135#15
Date:
2012-09-02 19:42:07 UTC
From:
To:
Dear Maintainer,

You can find some free maps at (assuming you're able unpack it):

http://www8.garmin.com/support/download_details.jsp?id=3645

Regards

#601135#20
Date:
2015-08-09 23:16:11 UTC
From:
To:
Hi Mouarfffff and Philippe,

I forwarded the bug to upstream to have a status of the Garmin
support. (ttps://github.com/navit-gps/navit/issues/16)
Note that it is still claimed as "being worked on" in their wiki.

Joseph

#601135#27
Date:
2015-12-08 00:40:44 UTC
From:
To:
Hi,

thanks for bringing up this bug report.

Unfortunately, I think as it stands this bug will need to be closed as
unreproducible.
Without having the file the bug reporter used, it's next to impossible
to tell what the problem was - in particular because there are different
versions / variations of the Garmin file format.

To test Navit's Garmin map driver, I just randomly grabbed a Garmin map
file off the Internet - I used the file from
http://www.miscjunk.org/mj/mp_mnohv.html , specifically
http://www.miscjunk.org/mj/downloads/mnohv_install.exe .
Running it (e.g. with wine) produces a file 88000001.img , which can be
loaded as a Navit map (map entry with type="garmin", enabled="yes",
data="/path/to/88000001.img").

Then moving to coordinates 47.4874N 92.4679W shows the streets of
Gilbert, Minnesota.

So the Garmin map driver (still) works in principle. Thus without a
reproducible test case (including a map file), I propose to close this
bug.

Greetings

Sebastian Leske

#601135#32
Date:
2015-12-21 12:13:21 UTC
From:
To:
Hi Sebastian,

Sebastian Leske a écrit le 08/12/2015 01:40 :

I confirm that the bug is reproducible. Back in 2010 the OP gave me
access to such a map file coming from a garmin GPS device. But I failed
solving the problem.

Thanks,

_g.

#601135#37
Date:
2015-12-22 23:30:27 UTC
From:
To:
Hi Gilles,

2015-⁠12-⁠21 13:13, Gilles Filippini:

Yes, that file would be helpful. Is there some way to obtain this file?
If yes, then I'll try to investigate the problem.

If not, then there is still no way to investigate further, so I'd still
propose closing the bug.

Greetings

S.Leske

#601135#42
Date:
2016-01-28 07:53:10 UTC
From:
To:
Gilles gave me access to an example Garmin file from a real device
(thanks!).  With that file, I can reproduce the problem described in
this bug.

It seems the current Garmin maps from Garmin use a format that has not
yet been reverse-engineered, and OP most likely used such a map.

It seems very unlikely that Navit will be the first to do this reverse
engineering work, as this is out of scope for Navit, and rather
difficult: The existing support for Garmin maps is based on an external
library (libgarmin), which has seen little development during the last
years. Also, the projects I could find that deal with Garmin maps focus
on creating Garmin maps (often from OpenStreetMap data), not on reading
original (and proprietary) Garmin maps (which, at any rate, may be
illegal in some countries).

I have documented this limitation in the Navit wiki under
http://wiki.navit-project.org/index.php/Garmin_maps .

Thus I'm tagging this bug as "wontfix".

Sebastian Leske

Navit developer
--------------------------------------

( https://bitbucket.org/maproom/qmapshack/issues/12/cannot-import-nt-format-map-file )

I also could not find any library/program that claims to read "NT
Format" Garmin files (apparently there are "pseudo-NT" files, which can
be read, but Garmin themselves produce "true" NT Files, which are
different).