New methods are proposed for the numerical evaluation of f (A) or f (A)b, where f (A) is a function such as A 1/2 or log(A) with singularities in (−∞, 0] and A is a matrix with eigenvalues on or near (0, ∞). The methods are based on combining contour integrals evaluated by the periodic trapezoid rule with conformal maps involving Jacobi elliptic functions. The convergence is geometric, so that ...

Conventional screening for Fetal Alcohol Syndrome in children involves time-consuming and intrusive facial distance measurements. We are developing an alternative method that will allow automatic measurement of the relevant distances from a pair of stereo photographs, as a screening aid. This paper describes a method for automatic extraction from such photographs of the points on the eyes used ...

Global warming, increasing CO2 concentration, and environmental disturbances affect grassland communities throughout the world. Here, we report on variations in the C3/C4 pattern of Inner Mongolian grassland derived from soil and vegetation. Soil samples from 149 sites covering an area of approximately 250 000 km within Inner Mongolia, People’s Republic of China were analyzed for the isotopic c...

This paper addresses the problem of articulated motion tracking from image sequences. We describe a method that relies on an explicit parameterization of the extremal contours in terms of the joint parameters of an associated kinematic model. The latter allows us to predict the extremal contours from the body-part primitives of an articulated model and to compare them with observed image contou...

This paper describes two new methods for the reconstruction of discrete surfaces from shading images. Both approaches are based on the reconstruction of a discrete surface by mixing photometric and geometric techniques. The processing of photometric information is based on reflectance maps, which are classic tools of Shape from Shading. The geometric features are extracted from the discrete sur...

New methods are proposed for the numerical evaluation of f(A) or f(A)b, where f(A) is a function such as A1/2 or log(A) with singularities in (−∞, 0] and A is a matrix with eigenvalues on or near (0,∞). The methods are based on combining contour integrals evaluated by the periodic trapezoid rule with conformal maps involving Jacobi elliptic functions. The convergence is geometric, so that the c...

A novel method is introduced to simultaneously recognize and segment time-varying human gestures from continuous video streams. Motion is represented by a 3D spatio-temporal surface based upon the evolution of a contour over time. The temporal endpoints of a gesture are estimated by Dynamically Time Warping the input sequence against a set of Compound Gesture Models, which are composed of the c...

MR Imaging techniques provide a non-invasive and accurate method for determining the ultra-structural features of human anatomy. In this study, we utilise a novel approach to segment out the ventricular system in a series of high resolution T1-weighted MR images. Our approach is based on an automated landmark extraction algorithm which automatically selects points along the contour of the ventr...

Topographical measurements of surfaces yield a lot of data which are usually presented by tables of height coordinates or by contour maps. Here a method is described to characterize the surface geometry by just a few parameters which quantify the functional properties: sphericity, twist and waviness. Examples of applications are given from the field of surface plate measurement. Some measuremen...

This paper describes two new methods for the reconstruction of discrete surfaces from shading images. Both approaches are based on the reconstruction of a discrete surface by mixing photometric and geometric techniques. The processing of photometric informations is based on reflectance maps which are classic tools of shape from shading. The geometric features are extracted from the discrete sur...