OpenStreetMap Forum

wonk

Member

Registered: 2008-11-15

Posts: 42

Newbie question: calibrating maps

Hi,
as new user I first want to test the maps. I want to export a map for Oziexplorer ( it uses image maps).
It is easy to export the image file, but I do not understand from the wiki, how to calibrate it. It seems to me from the wiki, that I have to show the calibrated points on the image and than create the calibration new with oziexplorer ???
Is there no image-file-format, which INCLUDES the calibration and can be converted in formats for different moving-map-programms?
                                                 Wolfgang

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Gruss, wonk

emj

Member

From: .se (59.3N17.99E) 0735969076

Registered: 2006-06-18

Posts: 949

Re: Newbie question: calibrating maps

At this moment no there is no such support, though if you ask Ozieexplorer to include support for Openstreetmap I'm sure they could add it quite easily if they have support for image tiling mechanisms.

How does oziexplorer want the georeference of images to be done?

JRA

Member

Registered: 2007-12-17

Posts: 677

Re: Newbie question: calibrating maps

Hi,

Two alternatives if you don't especially want to learn how to do calibration manually:
- OSM Map at http://alpo.hassinen.googlepages.com/osm-map
- Nik2img.py utility that is now in 0.2 version.  It can be used to create maps which are georeferenced with ESRI world files, and those can be imported with OziExplorer.  This involves installing PostGIS database, downloading osm2pgsql program and a little bit learning, but it would give fine results.  For example I have now a Mapnik map covering the whole city of Helsinki as an OziExplorer map on a PDA and it seems to be perfectly georeferenced.

wonk

Member

Registered: 2008-11-15

Posts: 42

Re: Newbie question: calibrating maps

Hi

Two alternatives if you don't especially want to learn how to do calibration manually:
- OSM Map at http://alpo.hassinen.googlepages.com/osm-map

Wow, that is a nordic language, I have no idea.
                     
        Wolfgang

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Gruss, wonk

wonk

Member

Registered: 2008-11-15

Posts: 42

Re: Newbie question: calibrating maps

Hi!

At this moment no there is no such support, though if you ask Ozieexplorer to include support for Openstreetmap I'm sure they could add it quite easily if they have support for image tiling mechanisms.

How does oziexplorer want the georeference of images to be done?

The calibration is written to a text-file, but the iamge-file is also converted in a for me unknown way.
I'll try now, to write down the coordinates of the exported region. That should be the edges of the image. If I fix this coordinates to the pixel-counts of the images edge, it schould get a calibration???
               
                                       Wolfgang

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Gruss, wonk

emj

Member

From: .se (59.3N17.99E) 0735969076

Registered: 2006-06-18

Posts: 949

Re: Newbie question: calibrating maps

Well. It's a bit harder the images are rendered in a spherical mercator, and you should reproject the export coordinates in to that.  These are not included because as far as I know there is no way to include that in the images you download.

Even though Finland is our brotherland and their cause is ours, Finnish is a Finno-Urgic language more relation with Hungerian than Swedish (scarily so). But then again it's still Nordic.. ;-)

JRA

Member

Registered: 2007-12-17

Posts: 677

Re: Newbie question: calibrating maps

Hi,

There is no need to understand much Finnish if you get the program installed. That goes by
- download the zip
- unzip it into c:\osm-map
- run c:\osm-map\setup

After that find your area in the map window showing OSM slippy map. When you are satisfied press "Lataa kuvat" ("Download images"). It downloads the image tiles on the local computer.  Then press "Tallenna kuva" ("Save image") to save the downloaded images in a single mosaiced image file.  If "Tallenna MAP" is selected it creates Ozi calibration file at the same and image is ready to be used in Ozi PC version, or to be converted to ozf3 format with Image to ofz program. You may contact the author and ask if he would like to translate the program.

wonk

Member

Registered: 2008-11-15

Posts: 42

Re: Newbie question: calibrating maps

Hi!

There is no need to understand much Finnish if you get the program installed. That goes by
- download the zip
- unzip it into c:\osm-map
- run c:\osm-map\setup

After that find your area in the map window showing OSM slippy map. When you are satisfied press "Lataa kuvat" ("Download images"). It downloads the image tiles on the local computer.  Then press "Tallenna kuva" ("Save image") to save the downloaded images in a single mosaiced image file.  If "Tallenna MAP" is selected it creates Ozi

Thank you.
It works after i found out, that is not possible to choose other directories.

                                           Wolfgang

---

Gruss, wonk

wonk

Member

Registered: 2008-11-15

Posts: 42

Re: Newbie question: calibrating maps

Hi!

There is no need to understand much Finnish if you get the program installed. That goes by
- download the zip
- unzip it into c:\osm-map
- run c:\osm-map\setup

After that find your area in the map window showing OSM slippy map. When you are satisfied press "Lataa kuvat" ("Download images"). It downloads the image tiles on the local computer.  Then press "Tallenna kuva" ("Save image") to save the downloaded images in a single mosaiced image file.  If "Tallenna MAP" is selected it creates Ozi

Thank you.
It works after i found out, that is not possible to choose other directories.

                                           Wolfgang

Hi,
as far as I see, the program has a small bug. In the map-file in the 9th line, I find "Map Projection,Transverse Mercator". In my opinion this should be "Map Projection,Mercator". With this correction I get exact positions. Could someone check this? As Newbie I don't want to write to the author, when I'm not sure.
                                                                     Wolfgang

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Gruss, wonk

JRA

Member

Registered: 2007-12-17

Posts: 677

Re: Newbie question: calibrating maps

You are probably right.  Using Mercator was suggested in the Ozi mailing list when I asked about what projection to use with these spherical Mercator which are not directly supported by OziExplorer.  I will check that some day and if it seems to be correct I can contact the author.
If you are using maps in PDA try also Osmarender layer.  For my mind it is better for outdoor use.

wonk

Member

Registered: 2008-11-15

Posts: 42

Re: Newbie question: calibrating maps

Hi!

If you are using maps in PDA try also Osmarender layer.  For my mind it is better for outdoor use.

I use a PDA. Do you mean to alter layers to get other icons depending on the scale?
That would be useful.
I think, I would have to install Osmarender for that?
                                 
                                                      Wolfgang

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Gruss, wonk

JRA

Member

Registered: 2007-12-17

Posts: 677

Re: Newbie question: calibrating maps

Hi,
I meant that OSM Map lets you select the layer in the main map window with the usual ble "+" button. Unfortunately not all of the servers on the menu are no more active and obviously they are hard coded in the program and user cannot add new servers.  But Mapnik and Tiles@home seem to work.