空间频率通道中噪声对体视匹配的影响

本工作希望了解噪声在各空间频率通道中对体视的影响.产生从5%至35%每隔5%的七个等级的随机点噪声图象,参照Wilson四通道模型的频率分别用两种不同滤波器对随机点立体图对(RDS)及噪声图象进行滤波,然后在各通道图对中加入不同通道噪声进行匹配观察.得到:1.高频通道的体视抗干扰能力高于低频通道.2.Gabor函数滤波后图对的体视抗干扰能力高于Butterworth滤波器滤波后的,但均低于未滤波的.3.当噪声大于15%时,低频噪声对低频图对及高频噪声对高、低频图对的体视匹配有抑制作用,而低频噪声对高频图对则影响很小.4.未滤波及各通道图对的最大噪声容限均不超过25%.

THE EFFECT OF NOISE ON STEREOPSIS IN DIFFERENT SPATIAL FREQUENCY CHANNELS

We attempted to understand the effect of noise on stereopsis in different spatial channels. Seven random noise images with noise level from 5% to 35% in every 5% interval were designed. These noise images and random-dot stereogram were filtered digitally by Butterworth filter and Gabor function filter with Centre frequency and band width as Wilson's four spatial frequency channels. Filtered stereograms added to the different noise images were examined under a stereoscope to see if any depth could be perceived.We get the results as follows.1. Stereoscopic noise tolerance in high frequency channel is greater than that in low frequency channel.2. Slereoscopic noise tolerance of unfiltered stereograms is the greatest, that of stereogram filtered by Gabor function filter is greater than that of stereogram filtered by Butterworth filter.3. When noise exceeds 15%, low frequency noise restrains the match between low frequency stereograms, so does high frequency noise to the match between low frequency stereograms or high frequency stereograms. However, low frequency noise has no effect on match between high frequency stereograms.4. The maximum noise tolerance of unfiltered stereogram and all stereograms of spatial frequency channels do not exceed 25%.