Desktop map calibration

The Desktop converter is too complicated for me. I have no idea what DATUM is. I wish I could just to specify two points in pixels of an image file (not the corners!) and two geographical coordinates of these points. That so simple and that works fine in other software I used.
Can you please, please do that?

Hi, zc2

DATUM is neccesary; I live in
41.6900 N, 2.6000 E in European 1950 Datum
41.6889 N, 2.5988 E in WGS 1984 Datum
If I do not tell OruxMaps what datum I used to calibrate the map, I could wake up tomorrow in my neighbor's bed

Probably you are using WGS 1984 datum, but OruxMapsDesktop can not suppose that.
There are hundreds of different datums, I will go gradually mapping datums used in other systems (Ozi, Compe,...) to those used in OruxMaps, to make it a task automatically, but is a difficult task. But this will only work with precalibrated maps, not with simple images, where you always will need to know which system of coordinates (datum + projection) are you using.

PROJECTION is recommended, for full accuracy. If you are working with maps no bigger than 20x20 km, you can suppose a "FLAT EARTH" projection.

Calibration points. Until now, OruxMaps used the coordinates of the corners because they are normally provided by other systems (ozi, compe,...). Next versions will give support to other calibration procedures.

orux

Yes, the bitmaps I need to use covers small area, I think the projection should be flat.
I'd understand it's importance of the datum, sayif I provide a map already with coordinates made according a some particular datum.
But I provide lat/lon I take from Google maps or MS MapPoint, I believe they use the same datum as the GPS does (if that makes any sense).

As a sample software I'd like to point to Track by trackthisout.com
It does exactly what I need But it works with Windows Mobile.

zc2 wrote:Yes, the bitmaps I need to use covers small area, I think the projection should be flat.
I'd understand it's importance of the datum, sayif I provide a map already with coordinates made according a some particular datum.
But I provide lat/lon I take from Google maps or MS MapPoint, I believe they use the same datum as the GPS does (if that makes any sense).

As a sample software I'd like to point to Track by trackthisout.com
It does exactly what I need But it works with Windows Mobile.

Hi, zc2;

You are right; Google maps workS with wgs 1984 datum, and trackthisout.com seems to work with google maps, then should use wgs 1984 datum. This is the datum used by GPS.

If you are working with maps downloaded from Google maps, then it is a "Mercator" projection.

This is the information that you need to calibrate a map, plus 2 or more point coordinates.

I am working in a new version of OruxMapsDesktop that lets you calibrate a map with 2 points (plus datum and projection information), but it will take me some days.

orux

Great news!
Thank you very much!

Good luck in your work and best wishes!