2,552 research outputs found
Minimal Solvers for Monocular Rolling Shutter Compensation under Ackermann Motion
Modern automotive vehicles are often equipped with a budget commercial
rolling shutter camera. These devices often produce distorted images due to the
inter-row delay of the camera while capturing the image. Recent methods for
monocular rolling shutter motion compensation utilize blur kernel and the
straightness property of line segments. However, these methods are limited to
handling rotational motion and also are not fast enough to operate in real
time. In this paper, we propose a minimal solver for the rolling shutter motion
compensation which assumes known vertical direction of the camera. Thanks to
the Ackermann motion model of vehicles which consists of only two motion
parameters, and two parameters for the simplified depth assumption that lead to
a 4-line algorithm. The proposed minimal solver estimates the rolling shutter
camera motion efficiently and accurately. The extensive experiments on real and
simulated datasets demonstrate the benefits of our approach in terms of
qualitative and quantitative results.Comment: Submitted to WACV 201
Wireless Software Synchronization of Multiple Distributed Cameras
We present a method for precisely time-synchronizing the capture of image
sequences from a collection of smartphone cameras connected over WiFi. Our
method is entirely software-based, has only modest hardware requirements, and
achieves an accuracy of less than 250 microseconds on unmodified commodity
hardware. It does not use image content and synchronizes cameras prior to
capture. The algorithm operates in two stages. In the first stage, we designate
one device as the leader and synchronize each client device's clock to it by
estimating network delay. Once clocks are synchronized, the second stage
initiates continuous image streaming, estimates the relative phase of image
timestamps between each client and the leader, and shifts the streams into
alignment. We quantitatively validate our results on a multi-camera rig imaging
a high-precision LED array and qualitatively demonstrate significant
improvements to multi-view stereo depth estimation and stitching of dynamic
scenes. We release as open source 'libsoftwaresync', an Android implementation
of our system, to inspire new types of collective capture applications.Comment: Main: 9 pages, 10 figures. Supplemental: 3 pages, 5 figure
- …