Geometry Processing of Conventionally Produced Mouse Brain Slice Images

Brain mapping research in most neuroanatomical laboratories relies on conventional processing techniques, which often introduce histological artifacts such as tissue tears and tissue loss. In this paper we present techniques and algorithms for automatic registration and 3D reconstruction of conventionally produced mouse brain slices in a standardized atlas space. This is achieved first by constructing a virtual 3D mouse brain model from annotated slices of Allen Reference Atlas (ARA). Virtual re-slicing of the reconstructed model generates ARA-based slice images corresponding to the microscopic images of histological brain sections. These image pairs are aligned using a geometric approach through contour images. Histological artifacts in the microscopic images are detected and removed using Constrained Delaunay Triangulation before performing global alignment. Finally, non-linear registration is performed by solving Laplace's equation with Dirichlet boundary conditions. Our methods provide significant improvements over previously reported registration techniques for the tested slices in 3D space, especially on slices with significant histological artifacts. Further, as an application we count the number of neurons in various anatomical regions using a dataset of 51 microscopic slices from a single mouse brain. This work represents a significant contribution to this subfield of neuroscience as it provides tools to neuroanatomist for analyzing and processing histological data.Comment: 14 pages, 11 figure

A Unified Architecture for the computation of B-Spline Curves and Surfaces

B-Splines in general, and Non-Uniform Rational B-Splines in particular, have become indispensable modeling primitives in computer graphics and geometric modeling applications. In this paper a novel high-performance architecture for the computation of uniform, non-uniform, rational and non-rational B-Spline curves and surfaces is presented. This architecture has been derived through a sequence of steps. First, a systolic architecture for the computation of the basis function values, the basis function evaluation array (the BFEA), is developed. Using the BFEA as its core, an architecture for the computation of non-uniform rational B-Spline curves is constructed. This architecture is then extended to compute NURBS surfaces. Finally, this architecture is augmented to compute the surface normals so that the output from this architecture can be directly used for rendering the NURBS surface. The overall linear structure of the architecture, its small I/O requirements, its non-dependence on t..

Immersive Teleconferencing: A New Algorithm to Generate Seamless Panoramic Video Imagery

This paper presents a new algorithm for immersive teleconferencing, which addresses the problem of registering and blending multiple images together to create a single seamless panorama. In the immersive teleconference paradigm, one frame of the teleconference is a panorama that is constructed from a compound-image sensing device. These frames are rendered at the remote site on a projection surface that surrounds the user, creating an immersive feeling of presence and participation in the teleconference. Our algorithm efficiently creates panoramic frames for a teleconference session that are both geometrically registered and intensity blended. We demonstrate a prototype that is able to capture images from a compound-image sensor, register them into a seamless panoramic frame, and render those panoramic frames on a projection surface at 30 frames per second