3D电视图片视差引发的EEG和VEP变化的研究

VEP and EEG Signal-Based Research on Different Parallax Images in 3D-TV

采集志愿者观看3D电视不同视差图片时的脑电信号,分析其在观看过程中产生的视觉诱发电位,计算各波段功率得到视觉疲劳因子R值,以此来探究3D影片中视差因素对人体健康的影响,为3D片源的制作提供一定的指标参考。基于Neuroscan脑电仪搭建实验系统,选取10名健康志愿者观看不同视差的3D图片,采集脑电信号的同时当其感觉不适时(刺痛感或者眩晕感)通过按键反馈。对采集的脑电信号中枕部视觉功能区的O1、O_z、O_2等3个导联的数据采取叠加平均的方法提取其视觉诱发电位(VEP),得到N_(135)成分波和P_(260)成分波;将预处理后的脑电信号依照相同的图片刺激序号进行叠加,将结果用Matlab的EEG工具包进行相对功率计算,进一步得到疲劳因子R值。结果表明,不同视差图片诱发的VEP的电位幅值和潜伏期有所差异,潜伏期的差异尤为明显(不同分组的均值变化为30%);志愿者观看只有负视差的3D图片时疲劳因子R值较大,即所有导联的均值比其他分组图片高10%。P_(260)成分的幅值和潜伏期可以作为评价3D片源的一个参考指标;负视差的图片更容易引起人眼的疲劳;正负视差都有的图片引起的疲劳度等级最低。

The EEG of volunteers was collected when they were watching 3D images with different parallaxes.The visual evoked potential（ VEP） of different images and the visual fatigue factor R were analyzed to explore the effects of parallax of 3D film on human body. Test systems were set up based on the Neuroscan electroencephalograph. Ten healthy volunteers received picture-stimulation of different parallaxes. A feedback button could be pressed when they felt discomfort（ tingling or vertigo）. Through the method of superimposed average,VEP was extracted based on three lead O1,Oz,and O2 in occipital domain of visual sense,obtaining N135 composition and P260 composition wave. The preprocessed ECG signals were superposed upon the same stimulus serial number. The fatigue factor R was obtained from the relative power calculated by the superposed signals with Matlab. Results showed that the amplitudes and the latency period of the VEP were not the same while watching different visual parallax images,especially for the latency period（ the variation of mean value between different groups was 30%）. The fatigue factor R was the biggest when volunteers watched negative parallax 3D images,and the average values of all leads were 10% higher than that when watching other groups.In conclusions,the P260component（ amplitude and incubation period） can be used to detect 3D pictures;Negative parallax images more likely make human eyes fatigue; Images with both positive and negative parallaxes is in the least possibility to cause fatigue.