Development of head-free remote eye gaze detection system

为了开发使用者可以将头部移动10 cm左右的非接触、远程视频、高精度的视线检测系统，进行了研究，以便使用视线向计算机输入信息。在最终的视线检测系统中，通过两个立体广角摄像机获取用户脸部的完整图像，从而精确地检测出瞳孔的三维位置。另一个窄的摄像机固定在一个云台单元上，对准用户的眼睛，并捕捉放大的眼睛图像。在图像中，检测瞳孔图像的中心和光源的角膜反射的中心。使用它们的相对位置，确定视线相对于窄相机的光轴的角度。在2003年以前，红外线发光二极管（LED）都是以立体摄像机的光圈为中心，呈环状排列。T的两个环 ...更多信息 LED与视频的奇/偶信号同步开启，并且在每个相机中交替地获得瞳孔和暗瞳孔图像。区分这些图像简化了瞳孔检测。计算瞳孔的三维位置，并使窄相机指向瞳孔。在窄摄像机上，在光圈附近和稍远的地方安装与立体宽摄像机不同波长的LED环，以同样的方式检测瞳孔，并在明亮的眼睛图像中检测肉体反射。2004财政年度，提出了眼睛注视校准方法，其利用眼球的光学具有围绕眼球的视轴轴对称的形状的假设。这可以很容易地校准眼睛凝视点，只需看一个已知的点在PC屏幕上和狭窄的相机。实验结果表明，检测到的眼睛注视点在屏幕的某些位置显示出系统误差。然而，屏幕与被试者面部之间的距离的变化不影响眼睛注视检测结果。实验结果表明了该方法的有效性。此外，当瞳孔边缘处存在角膜反射时，很难估计从窄相机获得的图像中的瞳孔中心。该问题的改进使得眼睛注视点在屏幕上的分散小于1.5cm。少

Studies for development of non-contact, remote video-based, high-precision eye-gaze detection systems in which users can move their head around 10 cm were conducted for information input into a computer using light of sight. In the principle of the final eye gaze detection system, the precise 3-D pupil position was detected by two stereo wide cameras which can grab whole image of users' face. Another narrow camera fixed on a pan-tilt unit was directed toward user's eye, and grabbed a magnified eye image. In the image, the center of the pupil image and the center of the corneal reflection of the light source were detected. Using their relative positions, the angle of the light of sight relative to the light axis of the narrow camera was determined. The intersection between the light of sight and the visual object was detected as the eye gaze point.Until 2003 fiscal year, the infrared LEDs were arranged in a ring shape around the aperture of each of the stereo cameras. The two rings of t … More he LEDs were switched on synchronously with an odd/even signal of the video and, the pupil and dark pupil images were alternately obtained in each camera. Diffentiating these images eased pupil detection. The 3D positions of the pupil was calculated and the narrow camera was made to direct toward the pupil. On the narrow camera, the rings of LEDs having a different wavelength from that of the stereo wide cameras were attached to near the aperture and a little far from there, and the pupil was detected in the same fashion, and the carnal reflection was detected in the bright eye image.In 2004 fiscal year, an eye gaze calibration method was proposed, which utilized an assumption that the optics of eye ball has a shape of axial symmetry around the visual axis of the eyeball. This could easily calibrate eye gaze point by just looking at one known point on a PC screen and the narrow camera. The experimental results indicated that the detected eye gaze points showed the systematic errors in some positions of the screen. However, the change of the distance between the screen and the face of the subject did not influence the eye gaze detection results. This result showed the efibctiveness of this eye gaze detection method. In addition, it was difficult to estimate the pupil center in the image obtained from the narrow camera when the oarneal reflection was located at the edge of the pupil. The improvement of this problem made the dispersion of the eye gaze point on the screen less than 1.5 cm. Less