BEGIN:VCALENDAR VERSION:2.0 PRODID:Linklings LLC BEGIN:VTIMEZONE TZID:Australia/Melbourne X-LIC-LOCATION:Australia/Melbourne BEGIN:DAYLIGHT TZOFFSETFROM:+1000 TZOFFSETTO:+1100 TZNAME:AEDT DTSTART:19721003T020000 RRULE:FREQ=YEARLY;BYMONTH=4;BYDAY=1SU END:DAYLIGHT BEGIN:STANDARD DTSTART:19721003T020000 TZOFFSETFROM:+1100 TZOFFSETTO:+1000 TZNAME:AEST RRULE:FREQ=YEARLY;BYMONTH=10;BYDAY=1SU END:STANDARD END:VTIMEZONE BEGIN:VEVENT DTSTAMP:20240214T070245Z LOCATION:Meeting Room C4.11\, Level 4 (Convention Centre) DTSTART;TZID=Australia/Melbourne:20231213T152000 DTEND;TZID=Australia/Melbourne:20231213T153000 UID:siggraphasia_SIGGRAPH Asia 2023_sess125_papers_208@linklings.com SUMMARY:SOL-NeRF: Sunlight Modeling for Outdoor Scene Decomposition and Re lighting DESCRIPTION:Technical Papers, TOG\n\nJia-Mu Sun and Tong Wu (Institute of Computing Technology, Chinese Academy of Sciences; University of Chinese A cademy of Sciences); Yong-Liang Yang (University of Bath); Yu-Kun Lai (Car diff University); and Lin Gao (Institute of Computing Technology, Chinese Academy of Sciences; University of Chinese Academy of Sciences)\n\nOutdoor scenes often involve large-scale geometry and complex unknown lighting co nditions, making it difficult to decompose them into geometry, reflectance and illumination. Recently researchers made attempts to decompose outdoor scenes using Neural Radiance Fields (NeRF) and learning-based lighting an d shadow representations. However, diverse lighting conditions and shadows in outdoor scenes are challenging for learning-based models. Moreover, ex isting methods may produce rough geometry and normal reconstruction and in troduce notable shading artifacts when the scene is rendered under a novel illumination. To solve the above problems, we propose SOL-NeRF to decompo se outdoor scenes with the help of a hybrid lighting representation and a signed distance field geometry reconstruction. We use a single Spherical G aussian (SG) lobe to approximate the sun lighting, and a first-order Spher ical Harmonic (SH) mixture to resemble the sky lighting. This hybrid repre sentation is specifically designed for outdoor settings, and compactly mod els the outdoor lighting, ensuring robustness and efficiency. The shadow o f the direct sun lighting can be obtained by casting the ray against the m esh extracted from the signed distance field, and the remaining shadow can be approximated by Ambient Occlusion (AO). Additionally, sun lighting col or prior and a relaxed Manhattan-world assumption can be further applied t o boost decomposition and relighting performance. When changing the lighti ng condition, our method can produce consistent relighting results with co rrect shadow effects. Experiments conducted on our hybrid lighting scheme and the entire decomposition pipeline show that our method achieves better reconstruction, decomposition, and relighting performance compared to pre vious methods both quantitatively and qualitatively.\n\nRegistration Categ ory: Full Access\n\nSession Chair: Michael Gharbi (Adobe, MIT) URL:https://asia.siggraph.org/2023/full-program?id=papers_208&sess=sess125 END:VEVENT END:VCALENDAR