PDF-Omni: Poincaré Dual Disk Distortion Field-based Recurrent Update for Omnidirectional Stereo Matching

Omnidirectional stereo matching (OSM) estimates 360◦ depthfrom multi-view fisheye images, where inherent fisheye distortion causessparse matching cues in seam regions. However, existing methods rely onspatially uniform update policies, degrading performance in these chal-lenging regions. To address this limitation, we propose PDF-Omni, ageometry-aware OSM framework built on a Poincaré Dual Disk distor-tion field that models spatially varying geometric uncertainty across seamregions. We introduce a distortion-informed GRU with distortion-awareattention to selectively expand the receptive field in high-uncertaintyregions while preserving efficiency in low-uncertainty ones. We furtherpresent a local entropy cumulative loss to supervise high-entropy costdistributions in ambiguous regions. Experimental results demonstratestate-of-the-art performance with consistent gains especially in seam re-gions. The code is available at https://github.com/ynskyang/PDF-Omni