Tool for Creating Custom Maps

[TomGo]

Hi
Making maps in kml/kmz format with Google Earth using an graphical map image file is cumbersome.
Assigning the image map to geographical positions by placing and stretching the image is
exhausting and imprecise.
I guess, there are tools, where the image file can be placed near a reference map like OSM and make the geographical reference by placing points the both of these maps.
Do you know about such tools to make custom maps ?

Thank you
Kind regards,
Tom

[Boyd]

Have a look at these

http://www.the-thorns.org.uk/mapping/
https://moagu.com/?page_id=155

The best approach is to start with imagery that is already georeferenced. Then it's just a matter of cutting it into tiles that meet Garmin's spec.

The other very useful tool is Mobile Atlas Creator (MOBAC)

http://mobac.sourceforge.net

I have adopted it as a method of distributing my own maps because of its versatility. The software runs on MacOS, Windows and Linux and can export maps that work on almost any platform - Android, iOS, Garmin Custom Maps, Magellan RMP and others.

The method I use to create maps in this format is rather complex, but the result is a system that's very easy for the end user. Here's one of many free maps on my site that uses Mobile Atlas Creator: https://boydsmaps.com/new-york-and-long-island-2017-orthoimagery/

I wrote a detailed tutorial for end users here: https://boydsmaps.com/docs/Using-Mobile-Atlas-Creator-with-Boyds-Maps.pdf

[MojaveMan]

I make a lot of custom maps.  I have found one of the biggest difficulties I have faced is that many maps use different "projections" than google earth or the garmin.  A good example of this is the topo maps and imagery that come from the USGS.  If you look at the map as provided from the USGS, it is mostly a trapezoid with the bottom slightly longer than the top - and more importantly if you look at the lat/long reference marks they are definitely not "square" as Google Earth is.  This is probably done like this so a simple measurement on the paper map is "true".
In order to rectify this I find these reference marks and measure them, and I figure out where the tick marks should be in order to square off the image.  I feed these measurements into free image manipulation software (imagemagick) using its "polynomial distortion" routine to force these tick-marks to be squared off.  The end result is that imagemagick "streches" the image (pixel by pixel) so that everything is shifted into place.
http://www.imagemagick.org/Usage/distorts/#polynomial
That makes georeferencing the topo map (and the image file) trivial.  They now have reference marks for the lat/long, and they are perfectly square as google earth needs.  Additionally, the shadow images I make from DEM files are also squared off (the DEM data is on a squared-off projection), so now the projections on the topo map and the shadow image match - it really makes a difference.
Just out of curiosity - does the map you are trying to georeference have any sort of callibration markings on it?  Is it a map I could download and take a peek at?
Jeff

[jolly47roger]

MAPC2MAPC will reproject from most existing projections, doing the calculations automatically.

[I declare an interest : I wrote it]

[MojaveMan]

Yes, I believe you and I have discussed MAPC2MAPC.  I found when I used it, that it munged my images terribly.  If I recall correctly, you stated that it was likely an API call you were making to windows - windows was altering the jpg compression and making my nice sharp topo lines into a blur...
I just found the email exchange we had - March 16, 2017
I would say you were very responsive and helpful to my questions, though.

I would like to add that for most applications, I bet MAPC2MAPC is a terrific solution.  In our email exchange, I referred to my process as having "stupid-high" standards which I may have to abandon.  Well, I'm not smart enough to have abandoned them....yet.

[Boyd]

qGIS is another way to re-project a map. Have only played around with it a bit myself (I use GlobalMapper) but qGIS is very powerful, and it's free.   https://docs.qgis.org/2.8/en/docs/training_manual/vector_analysis/reproject_transform.html

[Pooneil]

Do you know about such tools to make custom maps ?

I use QGIS to produce raster maps as a georeferenced tiff file.  Then convert to garmin compatible KMZ maps using G-Raster.

QGIS will also make georeferenced PDFs.  The 3.2 version is still a work in development but worth getting started on versus the older 2.18 long term release version.

[sandersg]

QGis comes with the osgeo4w shell  which implements GDAL.  It's command line but if you need the Clark 1866 ellipsoid for instance this is the app for you