EyeLink II Scene Camera User Manual
©
2004-2007 SR Research Ltd.
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calibrated region. To reduce the size of the saved overlay file, the user can
choose a video codec for file saving. If “Preview while saving” option is checked,
playback may pause briefly when saving the .avi file with the overlay graphics
on; the saved AVI file, however, will play fine.
IMPORTANT!
When archiving a
SceneLink experiment data, please make sure the original EDF file and video
files created during data collection are saved.
5.4 Mapping Gaze Data to Digital Video Coordinates and Getting Frame
Number in the ASC File
The SceneLink application records eye-movement data in the resolution set in
the display screen (e.g., 1024 * 768). The user can use EDF2ASC utility to
convert the coordinate of eye data into the digital video coordinate (720 * 480).
Once a lookup table is created for synchronized playback of eye movement data
over the scene video (see section 5.1), the EDF2ASC converter can also be used
to insert scene camera frame number messages in the ASC file. The following
command line switches can be used with the EDF2ASC converter.
-gazemap
outputs gaze data in avi coordinates (
-g
can also be used instead)
-insertframe inserts frame number (
-i
can also be used instead)
-scenecam same as using -gazemap -insertframe together
The following modifications have been introduced to the Data Viewer so that
scene camera video information can be extracted.
1)
Two new options “Enable SceneLink Gaze Mapping” and “Generate
SceneLink Frame Message” are added to the Data Loading preferences of
Data Viewer. The former allows users to specify in data viewing session
options to load EDF file with mapped gaze data to scene video
coordinates. The latter allows the user to specify in data viewing session
options to generate frame number messages when loading file. Please
make sure you have made these changes before loading the intended
EDF file.
2)
The following variables are added to the Sample Report and
Saccade/Fixation Report.
•
Sample Report:
