A system to track an uninstrumented conductor’s baton by computer vision techniques is developed. An initial seek mode locates a baton in an image frame without prior knowledge; a subsequent track mode uses temporal information to cope with motion blur and noise. The seek mode utilises the characteristic form of detected edges to guide a maximal intensity trace. The track mode enhances this tec...

In this paper, we tackle the problem of temporally consistent boundary detection and hierarchical segmentation in videos. While finding the best high-level reasoning of region assignments in videos is the focus of much recent research, temporal consistency in boundary detection has so far only rarely been tackled. We argue that temporally consistent boundaries are a key component to temporally ...

It is recognized that block-wise dependence is a key requirement for fragile watermarking schemes to thwart vector quantization attack. It has also been proved that dependence with deterministic or limited context is susceptible to transplantation attack or even simple cover-up attacks. In this work, we point out that traditional nondeterministic block-wise dependence is still vulnerable to cro...

Public bike sharing systems are important alternatives to motorized individual traffic and are gaining popularity in larger cities worldwide. In order to maintain user satisfaction, operators need to actively rebalance the systems so that there are enough bikes available for rental as well as sufficient free slots for returning them at each station. This is done by a vehicle fleet that moves bi...

The problem of estimating local motion in the presence of noise deserves a thorough system-theoretical analysis. In current textbooks, the predominant procedures are classified into differential (’optical flow’) approaches and matching (or correlation) methods. From a system-theoretical point of view, both classes can be interpreted as a set of linear filters followed by a simple nonlinear oper...

The border between the gray and white matter is defined by an abrupt change in average blood flow. This difference allows one to distinguish structure with [14C]iodoantipyrine autoradiography. The angioarchitecture of the cortical gray-white junction suggests that an air embolism might preferentially lodge in this border zone, and thus ischemia of the border might go unrecognized if one depende...

Many digital contrast enhancement techniques have been used in order to optimize the visual quality of the image for human or machine vision through gray-scale or histogram modifications [l-4]. All these methods try to enhance the contrast of the input image without measuring the contrast itself. Moreover there is no universal criterion or unifying theory specifying the validity of a given enha...

We present a procedure for the characterization and the linearization of the photoresist response to UV exposure for application to the gray-scale fabrication of diffractive optical elements. A simple and reliable model is presented as part of the characterization procedure. Application to the fabrication of surface-relief diffractive optical elements is presented, and theoretical predictions a...

A noninvasive method of estimating regional cerebral blood flow (rCBF) in premature and full-term babies has been developed. Based on a modification of the xenon-133 inhalation rCBF technique, this method uses eight extracranial NaI scintillation detectors and an i.v. bolus injection of xenon-133 (approximately 0.5 mCi/kg). Arterial xenon concentration was estimated with an external chest detec...