Polarized Optical-Flow Gyroscope

Abstract

We merge by generalization two principles of passive optical sensing of motion. One is common spatially resolved imaging, where motion induces temporal readout changes at high-contrast spatial features, as used in traditional optical-flow. The other is the polarization compass, where axial rotation induces temporal readout changes due to the change of incoming polarization angle, relative to the camera frame. The latter has traditionally been modeled for uniform objects. This merger generalizes the brightness constancy assumption and optical-flow, to handle polarization. It also generalizes the polarization compass concept to handle arbitrarily textured objects. This way, scene regions having partial polarization contribute to motion estimation, irrespective of their texture and non-uniformity. As an application, we derive and demonstrate passive sensing of differential ego-rotation around the camera optical axis.