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Revisiting radial distortion absolute pose

To model radial distortion there are two main approaches; either the image points are undistorted such that they correspond to pinhole projections, or the pinhole projections are distorted such that they align with the image measurements. Depending on the application, either of the two approaches can be more suitable. For example, distortion models are commonly used in Structure-from-Motion since

Why having 10,000 parameters in your camera model is better than twelve

Camera calibration is an essential first step in setting up 3D Computer Vision systems. Commonly used parametric camera models are limited to a few degrees of freedom and thus often do not optimally fit to complex real lens distortion. In contrast, generic camera models allow for very accurate calibration due to their flexibility. Despite this, they have seen little use in practice. In this paper,

From two rolling shutters to one global shutter

Most consumer cameras are equipped with electronic rolling shutter, leading to image distortions when the camera moves during image capture. We explore a surprisingly simple camera configuration that makes it possible to undo the rolling shutter distortion: two cameras mounted to have different rolling shutter directions. Such a setup is easy and cheap to build and it possesses the geometric const

Deep shutter unrolling network

We present a novel network for rolling shutter effect correction. Our network takes two consecutive rolling shutter images and estimates the corresponding global shutter image of the latest frame. The dense displacement field from a rolling shutter image to its corresponding global shutter image is estimated via a motion estimation network. The learned feature representation of a rolling shutter i

Online invariance selection for local feature descriptors

To be invariant, or not to be invariant: that is the question formulated in this work about local descriptors. A limitation of current feature descriptors is the trade-off between generalization and discriminative power: more invariance means less informative descriptors. We propose to overcome this limitation with a disentanglement of invariance in local descriptors and with an online selection o

Infrastructure-based multi-camera calibration using radial projections

Multi-camera systems are an important sensor platform for intelligent systems such as self-driving cars. Pattern-based calibration techniques can be used to calibrate the intrinsics of the cameras individually. However, extrinsic calibration of systems with little to no visual overlap between the cameras is a challenge. Given the camera intrinsics, infrastructure-based calibration techniques are a

Full-Field Electroretinography Changes Associated with Age-Related Macular Degeneration : A Systematic Review with Meta-Analyses

Background: The aim of this study was to systematically review the literature and to perform meta-analyses on full-field electroretinography (ffERG) between healthy controls and age-related macular degeneration (AMD) to map the extent of retinal dysfunction. Summary: We systematically searched 11 databases on 3 March 2021. Eligible studies had to measure retinal function using ffERG in eyes with A

Selecting predictive biomarkers from genomic data

Recently there have been tremendous efforts to develop statistical procedures which allow to determine subgroups of patients for which certain treatments are effective. This article focuses on the selection of prognostic and predictive genetic biomarkers based on a relatively large number of candidate Single Nucleotide Polymorphisms (SNPs). We consider models which include prognostic markers as ma

Bile leakage and the number of metal clips on the cystic duct during laparoscopic cholecystectomy

Background and objective: The most common way of closing the cystic duct in laparoscopic cholecystectomy is by using metal clips (>80%). Nevertheless, bile leakage occurs in 0.4%–2.0% of cases, and thus causes significant morbidity. However, the optimal number of clips needed to avoid bile leakage has not been determined. The primary aim of this study was to evaluate bile leakage and post-procedur

Dynamic epigenetic age mosaicism in the human atherosclerotic artery

Accelerated epigenetic ageing, a promising marker of disease risk, has been detected in peripheral blood cells of atherosclerotic patients, but evidence in the vascular wall is lacking. Understanding the trends of epigenetic ageing in the atheroma may provide insights into mechanisms of atherogenesis or identify targets for molecular therapy. We surveyed DNA methylation age in two human artery sam

Effects of Infant Massage : A Systematic Review

Infant massage is performed in various international contexts. There is a need for an updated literature review on this topic. The purpose of the current review was to investigate the effects of infant massage. A systematic literature review was conducted to investigate the effects of infant massage on the following outcomes: pain relief, jaundice, and weight gain. The inclusion criteria were infa

Backward Shift and Nearly Invariant Subspaces of Fock-type Spaces

We study the structure of the backward shift invariant and nearly invariant subspaces in weighted Fock-type spaces ℱWp, whose weight is not necessarily radial. We show that in the spaces ℱWp, which contain the polynomials as a dense subspace (in particular, in the radial case), all nontrivial backward shift invariant subspaces are of the form ℘n, that is, finite-dimensional subspaces consisting of

How slow is slow? Managing fire hydrant operation for protecting water infrastructure

There have been several water main breaks attributed to fire hydrant operations despite the persistent guidance from stakeholders to operate the hydrants “slowly.” Traditional water hammer simulations for determining the safe operational times for every hydrant can be tedious and impractical for most water utilities. While the rapid operation of certain hydrants can generate excessive pressures, m

The association between plasma metabolites and future risk of all-cause mortality

Background: Metabolite profiles provide snapshots of the overall effect of numerous exposures accumulated over life courses, which may lead to health outcomes in the future. Objective: We hypothesized that the risk of all-cause mortality is linked to alterations in metabolism earlier in life, which are reflected in plasma metabolite profiles. We aimed to identify plasma metabolites associated with

The grammaticalization of SIC : On narrative particles in Romance and Scandinavian

The Old Romance continuations of Latin sic, such as Old French si and Old Italian sì, involve four different functions, all of which are referred to here as sic. The first one, which is closest to the original Latin usage, is that of a lexical adverbial, while the other three are functional elements introducing main clauses: the second sic follows elements preposed to the verb, the third one intro

Privacy preserving structure-from-motion

Over the last years, visual localization and mapping solutions have been adopted by an increasing number of mixed reality and robotics systems. The recent trend towards cloud-based localization and mapping systems has raised significant privacy concerns. These are mainly grounded by the fact that these services require users to upload visual data to their servers, which can reveal potentially conf

Multiplier Tests and Subhomogeneity of Multiplier Algebras

Multipliers of reproducing kernel Hilbert spaces can be characterized in terms of positivity of n n matrices analogous to the classical Pick matrix. We study for which reproducing kernel Hilbert spaces it suffices to consider matrices of bounded size n. We connect this problem to the notion of subhomogeneity of non-selfadjoint operator algebras. Our main results show that multiplier algebras of ma

Handcrafted outlier detection revisited

Local feature matching is a critical part of many computer vision pipelines, including among others Structure-from-Motion, SLAM, and Visual Localization. However, due to limitations in the descriptors, raw matches are often contaminated by a majority of outliers. As a result, outlier detection is a fundamental problem in computer vision and a wide range of approaches, from simple checks based on d

Calibration-free structure-from-motion with calibrated radial trifocal tensors

In this paper we consider the problem of Structure-from-Motion from images with unknown intrinsic calibration. Instead of estimating the internal camera parameters through some self-calibration procedure, we propose to use a subset of the reprojection constraints that is invariant to radial displacement. This allows us to recover metric 3D reconstructions without explicitly estimating the cameras’