Abstract: A system for evaluating cognitive ability of a subject includes a display unit, an input unit, and a way-finding test module including a database and a test processor. The database stores two-dimensional map data and a three-dimensional model of a virtual environment. The three-dimensional model is comprised of surface elements representing features visible in the virtual environment. The test processor is operable to control the display unit to generate a map image corresponding to the two-dimensional map data during an initial stage of a way-finding test. The input unit is operable by the subject during a subsequent stage of the way-finding test to provide control signals to the test processor. The test processor is responsive to the control signals to select the surface elements corresponding to the features in the virtual environment that become visible, and to control the display unit to generate three-dimensional animation.

Abstract: A portal/non-portal image registration system for registering portal and non-portal images includes a user interface, an image preprocessing unit, a contour detecting unit, and an image registration unit. The user interface is operable for selecting points on portal and non-portal images. The image preprocessing unit is operable, with reference to the selected points, so as to adjust orientations and scales of the portal and non-portal images to obtain preprocessed portal and non-portal images. The contour detecting unit is operable so as to reconstruct contours of the preprocessed portal and non-portal images to obtain reconstructed portal and non-portal contours. The image registration unit includes a registering module operable so as to conduct image registration based upon feature information of the reconstructed portal and non-portal contours using Generalized Hough Transform.