Importing Digitized Coordinates

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Module information
Modules BESA Research Basic or higher
Version 5.2 or higher

How do I import digitized electrode coordinates and head surface points

Digitized electrode locations can be provided in a surface point file (extension *.sfp) in ASCII format. It is recommended that the first three digitized coordinates are the fiducials (fiduciary points), labeled FidNz, FidT9, FidT10, followed by electrodes, and possibly additional skin points. A detailed description of the file and how to import it is given in the BESA help files (chapter: Working with Electrodes and Surface Locations).

An example sfp file could look like this:

FidNz -10.89	0.04	-4.30FidT9 -0.61	-7.78	-5.24FidT10 -0.70	7.34	-5.86E1 -1.52	-2.31	6.98
E2 -1.65	-7.67	2.54
E3 -4.26	-8.31	-3.86
...

The file is read in using the Channel and digitized head surface point information dialog in menu "File → Head Surface Points and Sensors → Load Coordinate Files" (use CTRL-L key on the keyboard).

How do I check the result

You can check on the correct reading of the file using the Surface points window (menu "File → Head Surface Points and Sensors → View" or V on the keyboard).

See also the article Verify Electrode Coordinates.

Digitized head surface points dialog.png