Yoav Y. Schechner: Research

Visual Reverberations

An image acquired through a glass window is a superposition of two sources: a scene behind the window, and a reflection of a scene in front of the window. Light rays incident on the window are reflected back and forth inside the glass. Such internal reflections affect the radiance of both sources: a spatial effect is created of dimmed and shifted replications.

Our work generalizes the treatment of transparent scenes to deal with this effect. First, we present a physical model of the image formation. It turns out that each of the transmitted and reflected scenes undergoes a convolution with a particular point spread function (PSF), composed of distinct delta functions. Therefore, scene recovery involves inversion of these PSFs.

We analyze the fundamental limitations faced by any attempt to solve this inverse problem. We then present a solution approach. The approach is based on deconvolution by linear filtering and simple optimization. The input to the algorithm is a pair of frames, taken through a polarizing filter. The method is demonstrated experimentally.

Publications

1. Yaron Diamant and Yoav Y. Schechner, “Overcoming visual reverberations,” Proc. IEEE CVPR (2008).

Presentations

1. “Overcoming secondary reflections” (7.65 Mb, PowerPoint)

Related Research

1. Separation of Semi-Reflections using Polarization Analysis
2. Focus-based Separation of Transparent Layers
3. Blind Source Separation