THE EFFECT OF NOISE ON STEREOPSIS IN DIFFERENT SPATIAL FREQUENCY CHANNELS
空间频率通道中噪声对体视匹配的影响

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%.