Visual Object Tracking: The Initialisation Problem

Model initialisation is an important component of object tracking. Tracking algorithms are generally provided with the first frame of a sequence and a bounding box (BB) indicating the location of the object. This BB may contain a large number of background pixels in addition to the object and can lead to parts-based tracking algorithms initialising their object models in background regions of the BB. In this paper, we tackle this as a missing labels problem, marking pixels sufficiently away from the BB as belonging to the background and learning the labels of the unknown pixels. Three techniques, One-Class SVM (OC-SVM), Sampled-Based Background Model (SBBM) (a novel background model based on pixel samples), and Learning Based Digital Matting (LBDM), are adapted to the problem. These are evaluated with leave-one-video-out cross-validation on the VOT2016 tracking benchmark. Our evaluation shows both OC-SVMs and SBBM are capable of providing a good level of segmentation accuracy but are too parameter-dependent to be used in real-world scenarios. We show that LBDM achieves significantly increased performance with parameters selected by cross validation and we show that it is robust to parameter variation.Comment: 15th Conference on Computer and Robot Vision (CRV 2018). Source code available at https://github.com/georgedeath/initialisation-proble

Biomedical Ethics in the Soviet Union

*This is an abbreviated version of a paper presented first at a joint MIT-Harvard Faculty Seminar on the humanistic dimensions of Soviet Science on November 20, 1987, and then at the Western Michigan University Ethics Center on February 10, 1988. An expanded, fully documented version, under the title Soviet Biomedical Ethics will appear in a volume edited by Loren Graham, and tentatively entitled The Human Side of Soviet Science, Harvard University Press, 1989

Can Corporations Have Moral Responsibility?

Editor\u27s note: This paper was read at the eighth annual University of Dayton Philosophy Colloquium, held in 1979. The notion of collective moral responsibility has received relatively little treatment in the Anglo-American philosophical literature. This is surprising, given the increasingly widespread practice of ascribing moral responsibility to groups, peoples, and other collections of individuals. After World War II it was common for people to speak of the moral responsibility of the German people for Nazi atrocities; during the Viet Nam War many people accused America of immorality in carrying on an immoral war and using immoral tactics such as defoliation and napalm bombings; the whites in the United States have been said to be morally responsible for the plight of the blacks and responsible for making due reparation; and so on. There are many issues involved in the ascription of collective moral responsibility. In this paper I shall focus on collective responsibility as it pertains to corporations

Computers, Ethics and Business

When it comes to computers and computer-related activities, moral responsibility is in short supply. Our language often manifests the myth that computers are responsible and hence no one is to blame. This paper explores the idea that computer programmers are morally responsible for the consequences of their programming

On the evolution of young radio-loud AGN

This paper describes an investigation of the early evolution of extragalactic radio sources using samples of faint and bright Gigahertz Peaked Spectrum (GPS) and Compact Steep Spectrum (CSS) radio galaxies. Correlations found between their peak frequency, peak flux density and angular size provide strong evidence that synchrotron self absorption is the cause of the spectral turnovers, and indicate that young radio sources evolve in a self-similar way. In addition, the data seem to suggest that the sources are in equipartition while they evolve. If GPS sources evolve to large size radio sources, their redshift dependent birth-functions should be the same. Therefore, since the lifetimes of radio sources are thought to be short compared to the Hubble time, the observed difference in redshift distribution between GPS and large size sources must be due to a difference in slope of their luminosity functions. We argue that this slope is strongly affected by the luminosity evolution of the individual sources. A scenario for the luminosity evolution is proposed in which GPS sources increase in luminosity and large scale radio sources decrease in luminosity with time. This evolution scenario is expected for a ram-pressure confined radio source in a surrounding medium with a King profile density. In the inner parts of the King profile, the density of the medium is constant and the radio source builds up its luminosity, but after it grows large enough the density of th e surrounding medium declines and the luminosity of the radio source decreases. A comparison of the local luminosity function (LLF) of GPS galaxies with that of extended sources is a good test for this evolution scenario [abridged].Comment: LaTeX, 11 pages, 8 figures; Accepted by MNRAS. Related papers may be found at http://www.ast.cam.ac.uk/~snellen . Valuable comments of referee incorporated. More discussion on simulation