E T V I S I O N M A N U A L
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icon on the menu bar. After calibration the blue cross, superimposed on the scene video image,
should accurately show the subjects instantaneous point-of-gaze so long as the eye pupils are correctly
detected. (For some subjects, the pupil may not be detectable or pupil detection may not be stable
when they look at extreme positions near the edges or corners of the scene image field.)
The
Scene Image
window can be moved by dragging the title bar, can be resized by dragging a corner,
or can be set to “full screen” by clicking the “maximize” symbol on the
Scene Image
window title bar.
When the
Scene Image
window is maximized, the left and right eye windows are displayed at the
upper left and right corners. Left clicking anywhere on the maximized
Scene Image
window display
will cause it to cover the eye displays. Click the “restore” icon to return the window to normal size.
The
Scene Image
window display updates 30 times per sec. The underlying scene image is 1280x720
pixels (as is the resolution of the scene video file recordings). Resolution of the maximized real-time
Scene Image
display on the
ETVision
application may be slightly different depending on the laptop
screen resolution.
6.6.4
Data Display
window
Click the “Data Display" icon to bring up the
Data Display
window. It will first appear to the right of
the normal
Scene Image
window, but can be moved and resized in the usual way. It can also be
“maximized” to full screen and “restored” using the icons on the title bar. Click the “Data Display”
icon again to close the window.
The
Data Display
window shows point-of-gaze with respect to the scene camera graphically, as a
real-time X-Y plot point, and also displays real-time digital values for data computed by the system.
The “POG Display” area plots point-of-gaze as a moving spot on a display area that represents the two
dimensional either the head mounted camera scene space or, if in
ET3Space
mode, the current scene
plane surface. If “POG text” is checked, digital horizontal and vertical coordinate values will appear
just below the POG dot and travel with it. These values are in the form “
(h, v)”,
where h is the
horizontal coordinate and
v
is the vertical. Note that the X-Y plot essentially duplicates the movement
of the point-of-gaze cursor in the
Scene Image
window (described in the previous section), but without
the background image.
The real time digital values appear within the POG (point-of-gaze) plot display. If the “Display Gaze
Data” check box is checked, the gaze position values are displayed at the upper left corner of the POG
display. These values represent a position with respect to the 1280x720 scene camera image, reported
to the nearest hundredth. The upper left corner of the scene camera field has coordinates (0.00,0.00),
the lower right corner is (1280.00, 720.00), center is (640.00, 360.00), etc. If the “POG text” box is
checked, the same information is displayed just below the point-of-gaze dot on the X-Y plot.
If the “Display System Values” check box is checked, a set of additional values is displayed at the top
right corner of the POG display. These include external data values, manual event mark values, pupil
diameter values for both eyes, and corneal reflection (CR) diameter values for both CRs on each eye.
XDAT values are external data values that can optionally be sent by an external device via LAN
connection. Network communication protocol is described in a separate “Network Communication”