This paper describes shape analysis of the caudate nucleus structure in a large schizophrenia study (30 controls, 60 schizophrenics). Although analysis of the caudate has not drawn the same attention as the hippocampus, it is a key basal ganglia structure shown to present differences in early development (e.g. autism) and also to present changes due to drug treatment. Left and right caudate wer...

Posing objects in their upright orientations is the very first step of 3D shape analysis. However, 3D models in existing repositories may be far from their right orientations due to various reasons. In this paper, we present a data-driven method for 3D object upright orientation estimation using 3D Convolutional Networks (ConvNets), and the method is designed in the style of divide-and-conquer ...

We offer an overview a novel, comprehensive approach to the computational differential geometry of curves, with applications to shape analysis and discovery/recognition of objects in images. The main idea is to specify a space of curves with constraints suited to the application, and exploit the differential geometry of this space to solve optimization and inference problems. Applications of th...

We propose a shape analysis system based upon the description of landmarks with measurement covariance, which extends statistical linear modelling processes to ‘pseudo landmarks’ for scientific studies. We discuss the properties of our approach and how measurement covariances can be considered characteristic of the local shape. Our formulation includes corrections for parameter bias, induced by...

A main focus of statistical shape analysis is the description of variability of a population of geometric objects. In this paper, we present work in progress towards modeling the shape and pose variability of sets of multiple objects. Principal geodesic analysis (PGA) is the extension of the standard technique of principal component analysis (PCA) into the nonlinear Riemannian symmetric space o...

Biomedical imaging of large patient populations, both cross-sectionally and longitudinally, is becoming a standard technique for noninvasive, in-vivo studies of the pathophysiology of diseases and for monitoring drug treatment. In radiation oncology, imaging and extraction of anatomical organ geometry is a routine procedure for therapy planning an monitoring, and similar procedures are vital fo...

This work discusses an ongoing project for hands gesture recognition in computer vision systems. The proposed approach is based on the shape analysis tools introduced in [1]. More specifically, the wavelet transform will be used for generating features for the recognition of hand gestures based on contours.

Natural objects can be subject to various transformations yet still preserve properties that we refer to as invariants. Here, we use definitions of affine-invariant arclength for surfaces in R in order to extend the set of existing non-rigid shape analysis tools. We show that by re-defining the surface metric as its equi-affine version, the surface with its modified metric tensor can be treated...

A specimen of Holohalaelurus shark (Scyliorhinidae; Chondrichthyes) recently collected off southern Mozambique, represents a southward range extension of 2200km for the recently described, H. grennian Human 2006. This specimen presents not only a significant extension of its known distribution, but is also only the second female specimen known for this species. Moreover, the specimen exhibits m...

This paper presents a methodology for shape analysis of anatomical structures. A template shape is used as a unit, and a shape transformation mapping the template to a particular structure is used to quantify the shape of the structure with respect to the template. The geometric characteristics of the boundaries of the template and of an individual structure are used to deene corresponding regi...