This window offers the possibility of calibrating your video. Pressing on the Calibration tab will take you to the Calibration window. For this I often use a piece of recording in which a ruler or a piece of graph paper (I have plastinated a small piece of graph paper for this purpose) is visible on the screen. With the mouse, I click on the beginning of a mark and drag along the required distance, in this case 16 mm (the width of the electrodes was 16 mm). In the left panels, the amount of pixels and mm are indicated. Pressing the “mm” button, allows me to insert the correct distance. The other buttons makes it possible to select the location (X and Y) and orientation (vertical or horizontal) of the calibration scale in the next window.
If you already know the calibration of your video (because you have already analyzed previous segments), then you don’t have to measure anything on the screen and just fill in the appropriate values for “mm:” and “pixels:”.