|MAPC2MAPC Help pages : File >Load
File Load Calibrated Map
: Reads a calibration file that may be .map,
.gux, .tfw, .jpr, .mcd, .gmi., jgw, .pgw, .cal and .imp. KAP and
WCI files (combined image and calibration) can also be read. The file
is loaded into memory and datum or grid conversions performed. A
locate an image file may be needed; also to match datum names. A
.tfw file using UTM or Grid coordinates will also open a
dialogue needing input of the zone and Datum or the Grid details. If these details are present in a .prj file then no dialogue occurs.
The program will also open other files by using helper applications. These applications need to be installed on your system then use Edit>Locate to 'open' the relevant .exe file. This only needs to be done once unless you reinstall the helper applications:
KMZ uses 7-zip (7z.exe)
JP2 uses MRSidDecode (mrsiddecode.exe)
TIF (Geotiff) and PDF (GeoPDF) use GDAL (gdal_translate.exe)
File Load Image For Calibration : Loads an image file (.png, .jpr, .gif, .bmp or .tif) and displays it.
Choose how to calibrate the map : North/South/East/West, the Four corners, by clicking on the map and entering coordinates or from a file of points(see below).
Click at the top left to choose the way the file is calibrated : The Map Grid (Latitude/Longitude, OS Great Britain or UTM) and the Datum of the map (see below). Click on the map for each point and input the coordinates. For UTM and OS the Northings and Eastings are in metres (5 digits each for OS), for UTM only enter the numeric part of the zone (1 to 60). For latitude and longitude either enter whole degrees and minutes and seconds, whole degrees with decimal minutes or decimal degrees : 51 degrees 30 minutes 30 seconds OR 51 degrees 30.5 minutes OR 51.508333 degrees whichever is easier. And North/South and East/West. Between 2 and 30 points may be entered. Click at the top left to finish - you can then write calibrations and/or view the calibrated map. Right clicking on a completed calibration point allows it to be 'nudged' to an accurate position. There is a tutorial here.
To load and (re)calibrate an image with an embedded calibration (e.g. KAP or WCI charts) use File>Open Calibration then Edit>Recalibrate image
File Load Image for Calibration > From a file of points : Loads an image file as above then opens a file of WGS84 points (rxf,txf,mxf,plt,kml) then each click on the map is given the coordinates from that file. Particularly useful if calibrating from Google earth : draw a path, save as KML. Tutorial here.
File Load Image for Calibration > From a list of waypoints : Loads an image file as above then opens a file of WGS84 points (rxf,txf,mxf,plt,kml) then each click on the map shows the list and you can select one to give the coordinates of the point you clicked on the map. Useful if you can identify points on the map using, for example, Basecamp or Mapsource.
File Load via GDAL : Uses GDAL_Translate (see Edit) and FWTOOLS Listego (listegeo.exe) to load a range of image types including ECW. A full list is here.
File Build Map from Map Source : This builds a map from a store of 256x256 map tiles. The tiles can come from a Tile Server on the Internet or a local tile store that may be individual files, a SQLITE database, MBTILES or MGMAPS. The available tile sources are specified in a file 'tileurls.txt' distributed with the program and can be extended with Edit Map Sources. The area to be built can be defined with a loaded Track file (or files) (the map covers the extent of the GPX points with a one tile margin around), from a named place (uses Geonames and needs an Internet connection) or from coordinates. For a named place or coordinates, the extent of the map surrounding the place is specified as the size of the margin (so a 3 tile margin will extend 7 tiles wide and high making 49 in all)
This function operates in two modes which are chosen on the map source selection screen. The map can be loaded in the normal way and then edited and/or output Alternatively, the map can be loaded in a mode where it may be scrolled indefinitely but neither altered nor output. This can be useful for viewing a map (e.g choose 'York' as the place and immediately see a map of York) and for using the map source as a base for displaying and editing Tracks. In the first mode, zooming shrinks or stretches the map at the chosen zoom level; in the second mode the zoom levels are changed. If a place is reached for which there is no map in the map source at the requested zoom level then the second mode defaults to Open Street Map.
In the second mode, if you click the mouse with the CTRL key held down, an area of map around that point and at the currently displayed zoom level is selected and can be used as in the first mode. The size of the area (always square) can be specified as a number of tiles - but if any tracks have been loadewd with track manager - or drawn - then a rectangular area to cover the track(s) is selected.
Map tiles are held in a cache to improve speed of access.
Please note that if you publish a map built form a tile server you should attribute it to the source such as Open Street Map and conform to the terms and conditions of the server.
After the file is loaded, the program calculates the accuracy of the calibration. Also see the page about Calibration and Rubber Sheeting.