(발제) gaze awareness for video-conferencing: software approach +ieee multimedia 2000 -jim gemmel...
TRANSCRIPT
� ����� ������������������������������������ ������� ������������� �����
손보연������������
Gaze Awareness for Video-conferening: A Software Approach
Gemmell, J.; Toyama, K.; Zitnick, C.L.; Kang, T.; Seitz, S.;
Microsoft Res., San Francisco, CA
August 6, 2002
Boyeon Son December 8, 2011
Video Conferencing Research
Video conferencing began with Ives’ 1927 research at Bell labs
Some studies of group problem solving and task accomplishment found no advantage in videoconferencing over audio-only communication. ◦ Compared problem solving using video
conference to that using voice only, handwriting, and typing
◦ voice is only a little slower than video conf.
Video Conferencing Research
The negative results are in part due to technical problems
If video contributes to enhanced communications, it could prove valuable in other contexts, such as negotiations, sales, and relationship building.
Importance of Gaze Awareness
gaze awareness—and eye contact in particular—is extremely important in face-to-face communication ◦ Practical use
: Using gaze to direct turn-taking in conversation
◦ Abstract social values : People who use frequent eye contact are perceived as more attentive, friendly, cooperative, confident, mature, and sincere than those who avoid it
Loss of Gaze Awareness
Most videoconferencing systems make it impossible for participants to make eye contact or even to determine where or at what the other participants are looking
May in fact be a contributing factor in the failure of videoconferencing
Loss of Gaze Awareness
Parallax ◦ Disparity in the location
of the camera and that of the opponent’s eyes appeared in the display
◦ When participants look at each other, they stare into their displays
Gaze Awareness in Video Conf.
Unless people look directly into the camera, you will never perceive them as making eye contact with you
Conversely, if they’re looking into the camera, they will always appear to be looking at you, even when you move around
Hardware Solutions
Existing systems restore gaze awareness only by using special and typically expensive hardware ◦ Reducing parallax
by minimizing the disparity in the locations and the “eye-contact angle”
◦ half-silvered mirrors ◦ Pinhole cameras in dislays
Software Approach
Aims to develop an inexpensive videoconferencing system that supports two to four participant
System which works with cheap, commonly available hardware
Rendering
The system uses the vision information to extract the head from the video frame, correct the gaze, and place it in the virtual 3D space ◦ Replaces the eyes with synthetic eyes to aim
the gaze ◦ Adjusts the head pose
Eye Manipulation
Simply repositioning the pupils can change facial expression
The top eyelid has to move accordingly as a person looks up or down
Eye Manipulation
Altering Head Pose
Texture mapping ◦ Creates a 3D model in the shape of the
subject’s head ◦ Executes texture mapping, projecting the face
image form the video frame onto the model ◦ Rotate the model to any desired orientation
Altering Head Position
Conclusion
The Methods are still too slow and inaccurate
Video that supports gaze awareness—along with low-latency, high-quality audio and easy call set up—will mean that a videoconferencing system finally has a chance to succeed.