Effects Of spatial anti-aliasing methods for stereoscopic 3D image on visual comfort

Abstract

In stereoscopic 3D image viewing, there's a special problem that negative disparity causes frequency stretch, which results in a spatial-frequency aliasing — Disparity Adaptive Spatial Frequency Aliasing (DASFA). This problem potentially causes viewer discomfort. In order to eliminate this aliasing, the region of the stereoscopic 3D image with negative disparity need to be low-pass filtered. But few works focus on comparing effects of the filtering methods for DASFA elimination on visual comfort. In this paper, we compare the effects of three anti-aliasing filtering methods for stereoscopic 3D image on visual comfort: (1) multi-threshold anti-aliasing filtering — both left and right image are low-pass filtered with non-uniform cut-off frequency; (2) single-threshold anti-aliasing filtering — both image pair are low-pass filtered with uniform cut-off frequency; (3) asymmetric anti-aliasing filtering — right image filtered by the multi-threshold anti-aliasing filter, left image is unfiltered. We implement the three filtering systems and conduct a subjective experiment. The results show that: the multi-threshold method can improve visual comfort when the Absolute Value of Minimum Negative Disparity (AVMND) of a S3D image is not very large; but the single-threshold method will cause over-blurring and lead to visual discomfort; the effect of the asymmetric method is not obvious.