Depth from a polarisation + RGB stereo pair

Dizhong Zhu; William A. P. Smith

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arXiv · 1903.12061

Depth from a polarisation + RGB stereo pair

Dizhong Zhu·William A. P. Smith

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Abstract

In this paper, we propose a hybrid depth imaging system in which a polarisation camera is augmented by a second image from a standard digital camera. For this modest increase in equipment complexity over conventional shape-from-polarisation, we obtain a number of benefits that enable us to overcome longstanding problems with the polarisation shape cue. The stereo cue provides a depth map which, although coarse, is metrically accurate. This is used as a guide surface for disambiguation of the polarisation surface normal estimates using a higher order graphical model. In turn, these are used to estimate diffuse albedo. By extending a previous shape-from-polarisation method to the perspective case, we show how to compute dense, detailed maps of absolute depth, while retaining a linear formulation. We show that our hybrid method is able to recover dense 3D geometry that is superior to state-of-the-art shape-from-polarisation or two view stereo alone.

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BibTeX RIS

Dizhong Zhu, William A. P. Smith. 2019-04-03. Depth from a polarisation + RGB stereo pair. https://arxiv.org/abs/1903.12061

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