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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.