Enhanced Shadow Retargeting with Light-Source Estimation Using Flat Fresnel Lenses

Casas, Llogari; Fauconneau, Matthias; Kosek, Maggie; Mclister, Kieran; Mitchell, Kenny

Abstract

Shadow-retargeting maps depict the appearance of real shadows to virtual shadows given corresponding deformation of scene geometry, such that appearance is seamlessly maintained. By performing virtual shadow reconstruction from unoccluded real-shadow samples observed in the camera frame, this method efficiently recovers deformed shadow appearance. In this manuscript, we introduce a light-estimation approach that enables light-source detection using flat Fresnel lenses that allow this method to work without a set of pre-established conditions. We extend the adeptness of this approach by handling scenarios with multiple receiver surfaces and a non-grounded occluder with high accuracy. Results are presented on a range of objects, deformations, and illumination conditions in real-time Augmented Reality (AR) on a mobile device. We demonstrate the practical application of the method in generating otherwise laborious in-betweening frames for 3D printed stop-motion animation

Citation

Casas, L., Fauconneau, M., Kosek, M., Mclister, K., & Mitchell, K. (2019). Enhanced Shadow Retargeting with Light-Source Estimation Using Flat Fresnel Lenses. Computers, 8(2), Article 29. https://doi.org/10.3390/computers8020029

• Journal Article Type: Article
• Conference Name: CVGC2018
• Acceptance Date: Mar 26, 2019
• Online Publication Date: Apr 2, 2019
• Publication Date: Apr 2, 2019
• Deposit Date: Apr 2, 2019
• Publicly Available Date: Apr 3, 2019
• Journal: Computers
• Electronic ISSN: 2073-431X
• Publisher: MDPI
• Peer Reviewed: Peer Reviewed
• Volume: 8
• Issue: 2
• Article Number: 29
• Edition: Special Issue Selected Papers from the Computer Graphics & Visual Computing (CGVC 2018)
• DOI: https://doi.org/10.3390/computers8020029
• Keywords: Augmented reality; mixed reality; computer graphics; interactive graphics; human–computer interaction
• Public URL: http://researchrepository.napier.ac.uk/Output/1702408
• Publisher URL: https://www.mdpi.com/2073-431X/8/2/29
• Contract Date: Apr 2, 2019