Shape is one of the primary low level image features in the newly emerged Content Based Image Retrieval (CBIR). Many shape representations have been proposed, and they are generally classified into contour-based methods and region-based methods. Contour-based methods capture shape boundary features while ignore shape inner content. Region-based methods capture shape inner features while do not ...

This paper compares two methods for object localization from contours: shape context and chamfer matching of templates. In the light of our experiments, we suggest improvements to the shape context: Shape contexts are used to find corresponding features between model and image. In real images it is shown that the shape context is highly influenced by clutter, furthermore even when the object is...

Shape algebraic representations provide several advantages over more traditional geometric representations. The use of predicate logic formulations of shape and spatial relations provides a natural, intuitive way to extend shape representations of the shape grammar formalism to provide generalized, parametric grammars. Introduction Research in the use of grammars and similar production systems ...

Shape grammars have been introduced in architectural theory some decades ago. They have been applied to architectural construction methods (e.g. Chinese traditional wooden buildings) or for analyzing the design patterns of well-known architects (e.g. Palladio, Frank Lloyd-Wright). These examples demonstrated that complex geometrical shapes could be generated by a set of replacement rules out of...

We present a geometric approach for constructing shape atlases of sulcal curves on the human cortex. Sulci and gyri are represented as continuous open curves in R3, and their shapes are studied as elements of an infinite-dimensional sphere. This shape manifold has some nice properties--it is equipped with a Riemannian L2 metric on the tangent space and facilitates computational analyses and cor...

Each subregion of the amygdala is characterized by a distinct cytoarchitecture and function. However, most previous studies on sexual dimorphism and aging have assessed differences in the structure of the amygdala at the level of the amygdala in its entirety rather than at the subregional level. Using an amygdala subregional shape analysis, we investigated the effects of sex, age, and the sex ×...

A good charge transfer efficiency is very important for high-speed application CMOS image sensors. This paper presents a method to optimize the pinned-photodiode (PPD) shape, which is implemented in the 4T CMOS pixel for reducing the image lag of large area photodiode pixels. The new design allows combining a better light sensitivity with a good charge transfer. A CMOS image sensor test chip is...

The problem of efficiently finding images that are similar to a target image has attracted much attention in the image processing community and is rightly considered an information retrieval task. However, the problem of finding structure and regularities in large image datasets is an area in which data mining is beginning to make fundamental contributions. In this work, we consider the new pro...

For satellite remote sensing, radiances received at the sensor are not only affected by the atmosphere but also by the topographic properties of the terrain surface. As a result, atmospheric correction alone does not yield output images that truly reflect terrain surface properties, namely surface reflectance (bidirectional reflectance factor, BRF) of objects on the earth surface. Following the...

An important objective in weed management is the discrimination between grasses (monocots) and broad-leaved weeds (dicots), because these two weed groups can be appropriately controlled by specific herbicides. In fact, efficiency is higher if selective treatment is performed for each type of infestation instead of using a broadcast herbicide on the whole surface. This work proposes a strategy w...