MAPC2MAPC Help pages : Edit
How to ....
Grids and Datums
Map Images
System Issues

Edit Preferences and Settings : Allows a warning to be issued before an output file is overwrittten.   
                          : When creating a .tfw file from only two calibration points, the default is to
                             rotate the map. A preference allows you to stretch the map instead. This
                             may be needed if whatever is reading the .tfw file needs the 2nd and 3rd
                             lines to be zero. 
                           : When reading a .map, .jpr or .tfw file that is not WGS84 will write a WGS84 version 
                           : Size of tiles when tiling maps
                           : Whether to show a WGS84 latitude and longitude grid on calibrated maps
                           :  Set the DrawOrder and JPG quality for Garmin maps
                           :  To enable advanced tiling for Garmin : more control over tile sizes and ability to selectively          
                               remove tiles from the output KMZ file (eg a map of an island with areas of sea that are not
                           :  To select which calibration types are to be written
                           :  To choose to write JPG instead of PNG for map images and SQLITEDB mobile atlas - this
                               inherits the JPG qulaity settings from Garmin Maps

Edit Locate 7-Zip Program : Opens a dialogue box to locate "7z.exe". If this is done, 7-Zip will be invoked by the program to create the .kmz file for Garmin Custom Maps

Edit Locate MrSIDGeoDecode : Opens a dialogue box to locate "mrsidgeodecode.exe". If this is done, mrsiddecode will be invoked by the program to decode MrSID .sid and .jp2 georeferenced files into a .tif and .tfw. MrSIDDecide can be downloaded from the GeoExpress section of

Edit Locate GDAL_Translate : Opens a dialoge to locate GDAL_Translate.exe. Needed to load ECW, OXF2, OZFX3, GEOPDF, GEOTIF and othe files with GDAL. The best download of GDAL is at

Edit Locate SRTM2OSM : Opens a dialoge to locate SRTM2OSM.exe. Needed to load SRTM 10-metre contours
Edit functions change the map in memory, to preserve the result the map and calibrations need to be saved

Edit Rescale map  : Choose a percentage (10-90) by which to rescale the map.

Edit Crop Map  : Choose an area to crop (left click for top left, right click for bottom right)

Edit Fit Coordinates : A common occurence is to have a map that was drawn to a projection that is not equirectangular but latitude/longitude is the only calibration information. As part of the loading proccess the program displays the 'Average projection error in simple TFW' showing how far away the calibration appears to be from the original (For more details, see here) . If you know the original projection then this function calculates the best fit coefficients for that projection. For example, for a UTM map it will calculate the UTM northings and eastings of the calibration points. If you do not know the projection but have at least seven calibration points then this function can calculate a polynomial best fit. The best fit coefficients will then be used when creating a Garmin Custom Map or will be saved in a specific format in a .p2p file for later use. Or, they can be used with the Edit Warp function to reproject the map.

Edit Warp map  : If the original calibration was not a simple equirectangular Latitude/Longitude then this function (which may take some time to process) will reproject the map to an equirectangular one. If the map covers a large area and is not based on a simple projection then, in its original form, an exact Garmin custom map may not be created. As pixels are being resampled some loss of quality is inevitable. As part of this process the map will be oriented to the north.  A map with straight grid lines and curved latitude/longitude lines will now have straight latitude/longitude and a curved grid. For a map calibrated as a simple equirectangular Latitude/Longitude then this function rotates the map to point north. As maps are warped, any areas needed to infill the new bounding box are set as RGB 253,253,253. If the result is saved as a 8-bit PNG these will be transparent - but not all systems understand transparency.

Edit Load Track Overlay : Loads a file (plt,rxf,mxf, txf, gpx or kml) of track or route points. Choose whether to put these on the map as points or a line and their colour. Several files may be loaded in succession. When the file is written the overlays are included. Points may also specified as icons - identify a PNG file to be used whose middle is placed on the point. Anything white - or nearly white is ignored. See the pages on Map Pins for more information on marking points onto maps.

Edit Darken/Lighten image : Makes the image darker or lighter. Enter a number greater than 1 and less than 3. If pixel colours are in the range 0 to 255, the difference between the pixel's colour and 255 is multiplied (darken) or divided (lighten) by the number given.

Edit Sharpen Map : After warping or rescaling, a map may look blurred. This process sharpens the look of the image.

Edit Undo : Undoes the last Edit function. To preserve memory, only one level of Undo is available

Edit Forget Datum Match : Once two datum name have been matched, the program remembers the mathc and does not ask again. If you need to change the match then this will force the program to ask next time.

Edit Recalibrate map : Allows you to recalibrate a map, losing all previous calibration information.

Edit Load SRTM Contours : If you have an Internet connection and have installed and Located SRTM2OSM this will draw contours from the SRTM  (Shuttle Rdar Topography) database onto your map. Especially useful for maps from Open Street Map

Edit Fix Icons; Edit Save Icon Positions, Edit Create Waypoint Icons  : see the Pins page

Edit Map Sources : Allows you to define sources of Map Tiles (either locally on on the Internet) in addition to those supplied with the program.