Surface Nomral-based Spatial Propagation

Inspired by the spatial propagation mechanism utilized in the depth completion task \cite{NLSPN}, we introduce a normal incorporated non-local disparity propagation module in which we hub NDP to generate non-local affinities and offsets for spatial propagation at the disparity level. The motivation lies that the sampled pixels for edges and occluded regions are supposed to be selected. The propagation process aggregates disparities via plane affinity relations, which alleviates the phenomenon of disparity blurring at object edges due to frontal parallel windows. And the disparities in occluded areas are also optimized at the same time by being propagated from non-occluded areas where the predicted disparities are with high confidence.