Minimal Rolling Shutter Absolute Pose with Unknown Focal Length and Radial Distortion

Zuzana Kukelova, Cenek Albl, Akihiro Sugimoto, Konrad Schindler, Tomas Pajdla

Abstract:

The internal geometry of most modern consumer cameras is
not adequately described by the perspective projection. Almost all cameras exhibit some radial lens distortion and are equipped with electronic
rolling shutter that induces distortions when the camera moves during
the image capture. When focal length has not been calibrated offline, the
parameters that describe the radial and rolling shutter distortions are
usually unknown. While, for global shutter cameras, minimal solvers for
the absolute camera pose and unknown focal length and radial distortion
are available, solvers for the rolling shutter were missing. We present the
first minimal solutions for the absolute pose of a rolling shutter camera
with unknown rolling shutter parameters, focal length, and radial distortion. Our new minimal solvers combine iterative schemes designed for
calibrated rolling shutter cameras with fast generalized eigenvalue and
Gr¨obner basis solvers. In a series of experiments, with both synthetic
and real data, we show that our new solvers provide accurate estimates
of the camera pose, rolling shutter parameters, focal length, and radial
distortion parameters. The implementation of our solvers is available at
github.com/CenekAlbl/RnP.