Calibrating Map Images - GPS TrackMaker Reference Manual

11.3 Calibrating Map Images

How to Calibrate a Map Image
To configure the program for the map coordinates inserted in the background of the screen, first load an image
through Tools > Insert Map Image button
the button will be enabled and the button
GTM PRO® will also show the Map Rotation Tool
GPS TrackMaker® uses a process of calibration with two stages:
1 – Image rotation to match the angle of the map grid with the program grid.
2 – Image calibration with two points, changing the position, height and width of the image.
The rotation stage is available only in GTM PRO®. To calibrate images in free version of the program, be sure the
image is already rotated.
Rotating the Image before calibrating with two points
If the inserted image is rotated, it won't be possible to calibrate it with two points. It is necessary to rotate the
image to match the image grid with the grid of the program.
To know how to rotate images in GTM PRO®, see the topic
Calibrating the Map through the Points of the Extremities of the Image
To know how to calibrate an image this way, see
or by pressing F7. The map will appear in the center of the screen,
will appear to its side.
After rotated, an easy way to calibrate map images is through the indication
of the coordinates of the upper-left and lower-right corners of the image.
This method, in spite of being easier, can't provide good precision because its
not always that it is possible to obtain the values of the extremities of the
map in a precise way, mainly when there are borders at the map or
generated in scan process.
Calibrating Images through Extremities
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and the Map Clipping Tool
Rotating Images.
.
Points.