such interaction. In this paper, we focus attention on
student’s face orientation, as one of the non-verbal
interaction occur in the classroom. We propose a
new method that generates lecture archiving content
based on students’ attention, that is, using their face
orientation. We consider that our acquisition
technology helps lecturer to grasp students’
condition and ROI (Region of Interest). Lecturers
can use students’ attention for improving lecture
method.
Figure 1: Equipment layout in the classroom.
In Section 2, we describe the overview of our lecture
archiving method. Then in Section 3, we describe
the acquisition of lecturer and students’ actions
occur in the classroom, and we propose a new
lecture archiving system based on interactions
between lecturer and student in Section 4.
2 OVERVIEW OF OUR LECTURE
ARCHIVE SYSTEM
In this section, we describe the overview of lecture
archiving system. We have been developing
automatic lecture archiving system that records
various information, such as lecturer and students’
voice, video, presentation slide and written
text/figure on whiteboard (Marutani et. al., 2006).
Figure 1 shows equipment layout in the
classroom. There are three screens at the front of
classroom; as a student’s view, presentation slide are
displayed on the left and center screen, written
text/figure on the whiteboard are displayed on the
right screen. The cameras located at rear side, right
side and left side of the classroom shoot lecturer,
and the three cameras located at front side are
shooting students. Furthermore, the system acquires
lecturer’s position and movement by the ultrasonic
location sensors, which set on roof, lecturer and
indication device.
Our lecture archiving system records and
synchronizes audio/video of lecturer and students,
presentation slide, written text/figure on the
whiteboard, then provide these data as a lecture
archiving system.
3 ACQUISITION OF ACTIONS IN
CLASSROOM
We have been working for the acquisition of time
sequential context occurs in the classroom, such as
lecturer’s action and movement; utterance, pointing
and writing whiteboard, and student’s action; face-
raising or note-taking (Marutani et. al., 2006),
(Hattori et. al., 2008).
3.1 Acquisition of Lecturer’s Action
In the classroom, there are three major classes of
lecturer’s action based on lecturer’s location and
orientation; descant, explanation of presentation
slide and explanation of text/figure on whiteboard.
Our system acquires these lecturer’s actions using
various sensors in the classroom. Ultrasonic location
sensors; installed on roof, lecturer and indication
device, given location information of lecturer and
pointing information. The archiving system records
the contents of slide and time to changing slide,
furthermore, contents of written text/figure on
whiteboard and time when the text/figure are
written. Then the system acquires lecturer’s actions.
3.2 Acquisition of Students’ Action
Three cameras located at the front of classroom
shoot students’ actions. Left camera is set up at the
top of left side screen, right camera is set up at the
top of right screen, and all three cameras focus on
center zone of students’ area. Then we acquire
students’ face orientation utilizing detecting faces
from recorded images.
Now, we categorize student’s action in the
classroom into four types; hear the lecturer’s
explanations, view a front screen, view a whiteboard
and take lecture notes. We identify these four types
based on installation position of equipments and
student’s face orientation.
3.3 Detecting Student’s Face
We experiment to verify the possibility of realize the
new archiving method based on student’s face
orientation. In usual, when lecturer explains using
left screen, students view left screen. At that time,
STUDY ON ACQUISITION OF LECTURER AND STUDENTS ACTIONS IN THE CLASSROOM
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