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Computational plenoptic image acquisition and display

University of British Columbia

Recent advances in camera technology, computing hardware, and optical fabrication have led to the emergence of computational photography, a field exploring the joint design of optical light modulation and computational processing. While conventional cameras record two-dimensional images, the "ultimate" computational camera would capture all visual information with a single shot. The amount of control over such high-dimensional data is unprecedented: dynamic range, depth of field, focus, colour gamut, and time scale of a photograph can be interactively controlled in post-processing. Required visual properties include the colour spectrum as well as spatial, temporal, and directional light variation - the plenoptic function. Unfortunately, digital sensors optically integrate over the plenoptic dimensions; most of the desired information is irreversibly lost in the process. We explore the multiplexed acquisition of the plenoptic function in this thesis. For this purpose, we introduce a mathematical framework that models plenoptic light modulation and corresponding computational processing. This framework not only allows us to evaluate and optimize the optical components of computational cameras, but also subsequent reconstructions. The combined design of optical modulation and computational processing is not only useful for photography, displays benefit from similar ideas. Within this scope, we propose multi-layer architectures and corresponding optimization schemes for glasses-free 3D display. Compared to conventional automultiscopic displays, our devices optimize brightness, resolution, and depth of field while preserving thin form factors. In a different application, adaptive coded apertures are introduced to projection displays as next-generation auto-iris systems. Combined with computational processing that exploits limitations of human perception, these systems increase the depth of field and temporal contrast of conventional projectors. With computational optics, integrated into sunglasses or car windshields, the capabilities of the human visual system can be extended. By optically modulating perceived intensities and colours, we demonstrate applications to contrast manipulation, preattentive object detection, and visual aids for the colour blind. Finally, we introduce computational probes as high-dimensional displays designed for computer vision applications, rather than for direct view. These probes optically encode refraction caused by transparent phenomena into observable changes in colour and intensity. Novel coding schemes enable single-shot reconstructions of transparent, refractive objects.

Text

2011-09-29

Attribution-NonCommercial-NoDerivatives 4.0 International

http://hdl.handle.net/2429/37674

Computer Science

University of British Columbia

UBCV

http://creativecommons.org/licenses/by-nc-nd/4.0/