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Light transport contains all light information between a light source and an image sensor. As an important application of light transport, dual photography has been a popular research topic, but it is challenged by long acquisition time, low signal-to-noise ratio, and the storage or processing of a large number of measurements. In this Letter, we propose a novel hardware setup that combines a flying-spot micro-electro mechanical system (MEMS) modulated projector with an event camera to implement dual photography for 3D scanning in both line-of-sight (LoS) and non-line-of-sight (NLoS) scenes with a transparent object. In particular, we achieved depth extraction from the LoS scenes and 3D reconstruction of the object in a NLoS scene using event light transport.
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Dense Lissajous sampling and interpolation for dynamic light-transport
Light-transport represents the complex interactions of light in a scene. Fast, compressed, and accurate light-transport capture for dynamic scenes is an open challenge in vision and graphics. In this paper, we integrate the classical idea of Lissajous sampling with novel control strategies fordynamic light-transport applicationssuch as relighting water drops and seeing around corners. In particular, this paper introduces an improved Lissajous projector hardware design and discusses calibration and capture for a microelectromechanical (MEMS) mirror-based projector. Further, we show progress towards speeding up the hardware-based Lissajous subsampling for dual light transport frames, and investigate interpolation algorithms for recovering back the missing data. Our captured dynamic light transport results show complex light scattering effects for dense angular sampling, and we also show dual non-line-of-sight (NLoS) capture of dynamic scenes. This work is the first step towards adaptive Lissajous control for dynamic light-transport.
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- PAR ID:
- 10231839
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optics Express
- Volume:
- 29
- Issue:
- 12
- ISSN:
- 1094-4087; OPEXFF
- Format(s):
- Medium: X Size: Article No. 18362
- Size(s):
- Article No. 18362
- Sponsoring Org:
- National Science Foundation
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