1 Multi - View People Counting System – Pedestrian Representation

In this chapter, a multi-view people counting system is presented. This system uses as the input data the video sequences acquired by a camcorder. The camcorder can be mounted anywhere (e.g., below a ceiling, on a side wall, or at a corner) with any viewing direction. In order to manage various appearances of people, a multi-view representation of pedestrian is introduced. This representation is characterized by a unit sphere, called the viewsphere. The viewsphere is composed of a number of nested spherical layers all centered at the core of the viewsphere. Each layer forms a 2D manifold of viewing directions (viewpoints), which are uniformly distributed over the layer. Pedestrian views generated according to the viewpoints of the viewsphere are clustered into so-called aspects. The pedestrian views within an aspect possess the same characteristics of silhouette.