Abstract: Some aspects include a virtual reality device configured to present to a user a virtual environment. The virtual reality device comprises a tracking device including at least one camera to acquire image data, the tracking device, when worn by the user, configured to determine a position associated with the user and a stereoscopic display device configured to display at least a portion of a representation of the virtual environment, wherein the representation of the virtual environment is based, at least in part, on the determined position associated with the user, wherein the display device and the tracking device are configured to be worn by the user.

Abstract: A method for the problem of reconstructing a watertight surface defined by an implicit equation from a finite set of oriented points. As in other surface reconstruction approaches disctretizations of this continuous formulation reduce to the solution of sparse least-squares problems. Rather than forcing the implicit function to approximate the indicator function of the volume bounded by the surface, in the present formulation the implicit function is a smooth approximation of the signed distance function to the surface. Then solution thus introduced is a very simple hybrid FE/FD discretization, which together with an octree partitioning of space, and the Dual Marching Cubes algorithm produces accurate and adaptive meshes.

Abstract: A method that estimates the coordinates of the calibration points in the projector image plane using local homographies obtained from the imaging camera. First, a dense set of correspondences between projector and camera pixels is found by projecting onto the calibration object an identical pattern sequence as the one later projected when scanning the target, reusing most of the software components written for the scanning application. Second, the set of correspondences is used to compute a group of local homographies that allow projection back of any of the points in the calibration object onto the projector image plane with sub-pixel precision. In the end, the data projector is then calibrated as a normal camera.

Abstract: In some aspects, a multi-camera device to facilitate multiple camera video conferencing is provided. The multi-camera device comprises a plurality of input ports, each configured to receive video information when connected to a respective external video camera, an output port configured to output video information, and a selection component coupled to the plurality of input ports and the output port, the selection component configured to provide video information received by at least one of the input ports to the output port for output to an external computer.

Abstract: Methods, structures and systems for encoding and decoding isosurface data. An encoder process takes volume data and an isolevel as input and produces compressed isosurface data as output. The compressed isosurface data produced by an encoder process is composed of an occupancy image record, an optional intersection points record, and an optional normal vectors record. An occupancy image is compressed with a context-based arithmetic encoder. Compressed isosurface data can be stored in a data storage device or transmitted through a communication medium to a remote computer system, where the decoder process is executed. The decoder processes take compressed surface data as input and produce surface data as output. The decoder processes first reconstructs the occupancy image by decoding the occupancy image record. An in-core isosurface decoder process produces a polygon mesh as a surface representation. An out-of-core isosurface decoder process produces a set of oriented points as a surface representation.

Abstract: An apparatus and method determine a 3D shape of an object in a scene. The object is illuminated to cast multiple silhouettes on a diffusing screen coplanar and in close proximity to a mask. A single image acquired of the diffusing screen is partitioned into subview according to the silhouettes. A visual hull of the object is then constructed according to isosurfaces of the binary images to approximate the 3D shape of the object.

Abstract: Methods and apparatus solving problems of polygonal approximations of isosurfaces extracted from uniformly sampled volumes increasing in size due to the availability of higher resolution imaging techniques. The large number of primitives represented hinders the interactive exploration of the dataset. Examples of methods are provided for adaptive isosurface extraction that are generally easy to implement and allows the user to decide the degree of adaptivity as well as the choice of isosurface extraction algorithm. The extraction of the isosurface is optimized by warping the volume. In a warped volume, areas of importance (e.g. containing significant details) are inflated while unimportant ones are contracted. Once the volume is warped, any extraction algorithm can be applied. The extracted mesh is subsequently unwarped such that the warped areas are rescaled to their initial proportions. The resulting isosurface is represented by a mesh that is more densely sampled in regions decided as important.

Abstract: Methods, structures and systems for encoding and decoding isosurface data. An encoder process takes volume data and an isolevel as input and produces compressed isosurface data as output. The compressed isosurface data produced by an encoder process is composed of an occupancy image record, an optional intersection points record, and an optional normal vectors record. An occupancy image is compressed with a context-based arithmetic encoder. Compressed isosurface data can be stored in a data storage device or transmitted through a communication medium to a remote computer system, where the decoder process is executed. The decoder processes take compressed surface data as input and produce surface data as output. The decoder processes first reconstructs the occupancy image by decoding the occupancy image record. An in-core isosurface decoder process produces a polygon mesh as a surface representation. An out-of-core isosurface decoder process produces a set of oriented points as a surface representation.

Abstract: Methods, structures and systems for encoding and decoding isosurface data. An encoder process takes volume data and an isolevel as input and produces compressed isosurface data as output. The compressed isosurface data produced by an encoder process is composed of an occupancy image record, an optional intersection points record, and an optional normal vectors record. An occupancy image is compressed with a context-based arithmetic encoder. Compressed isosurface data can be stored in a data storage device or transmitted through a communication medium to a remote computer system, where the decoder process is executed. The decoder processes take compressed surface data as input and produce surface data as output. The decoder processes first reconstructs the occupancy image by decoding the occupancy image record. An in-core isosurface decoder process produces a polygon mesh as a surface representation. An out-of-core isosurface decoder process produces a set of oriented points as a surface representation.

Abstract: A method, system, and computer program product for adjusting a unit image area within an input image according to information importance within the unit area. An image receiver configured to receive the input image. An image warper is coupled to an importance map as is configured to generate a warped image such that regions of higher importance in the input image are expanded in the warped image and regions of lower importance in the input image are compressed in the warped image. The importance map is configured to delineate the regions of higher importance and the regions of lower importance in the input image. Texture coordinates may also be warped in a similar manner. Thus, the image is unwarped automatically by modern graphics adapters having texture mapping capabilities.

Abstract: Disclosed are an image editing user interface system and method. The system includes one or more computers with one or more graphical user interfaces, and a receiving process for receiving one or more rendered two dimensional images on the computer graphical user interface. Each two dimensional image represents reflected light from a lit three dimensional object model, and the reflective light at each point of the two dimensional image corresponds to an object point on the three dimensional object model. The system further includes a changing process for changing a portion of the two dimensional image by changing the light intensity at a set of one or more points on the two dimensional image. The change in light intensity at the set of points causes a change in the three dimensional model to correspond to the change in the light intensity.

Abstract: A computer system, method, and article of manufacture for shading graphical objects and/or displays is disclosed. A graphical geometric data structure has a plurality of vertex positions defining one or more polygons, typically triangles. In a preferred embodiment, the polygons define a wireframe representation of a geometric object. Each of the vertex positions is associated with one or more sets of vertex color information. A color table has one or more fill colors to be rendered (shaded) between two or more of the vertex positions on a rendering of the geometric object. These colors can uniformly vary between the vertices of the triangle over the entire surface. A substitute color is associated with each of the fill colors so that at least two of the fill colors are associated with the same substitute color.

Abstract: The present invention smoothes a spherical graph signal composed of spherical signal points associated with graph vertices of a graph producing a smoothed spherical graph signal composed of smoothed spherical signal points. Each smoothed spherical signal point is computed by multiplying a vertex rotation matrix by the corresponding spherical signal point. The vertex rotation matrix is computed as a weighted average of neighbor rotation matrices using a local parameterization of the group of rotations. The present invention also filters anisotropically a graph signal composed signal points associated with graph vertices of a graph producing a filtered graph signal composed of filtered signal points. Each filtered signal point is computed as a weighted average of signal points corresponding to the corresponding graph vertices and neighbor graph vertices with neighbor weight matrices. The present invention also denoises the vertex positions of a polygon mesh without tangential drift.

Abstract: A computer system, method, and article of manufacture for shading graphical objects and/or displays is disclosed. A graphical geometric data structure has a plurality of vertex positions defining one or more polygons, typically triangles. In a preferred embodiment, the polygons define a wireframe representation of a geometric object. Each of the vertex positions is associated with one or more sets of vertex color information. A color table has one or more fill colors to be rendered (shaded) between two or more of the vertex positions on a rendering of the geometric object. These colors can uniformly vary between the vertices of the triangle over the entire surface. A substitute color is associated with each of the fill colors so that at least two of the fill colors are associated with the same substitute color.

Abstract: A method and apparatus are disclosed for finding a triangle mesh that interpolates a set of points obtained from a scanning system. A ball-pivoting algorithm computes a triangle mesh interpolating a given point cloud. The disclosed ball-pivoting algorithm triangulates a set of points by “rolling” a ball of radius r on the point cloud. The points are surface samples acquired with multiple range scans of an object. The ball-pivoting algorithm starts with a seed triangle, and pivots the ball of a given radius, r, around an edge of the triangle. During the pivoting operation, the ball revolves around the edge while keeping in contact with the edge's endpoints. The ball pivots until it touches another scan point, forming another triangle. The ball-pivoting operation continues until all reachable edges have been tried, and then starts from another seed triangle, until all scan points have been considered.

Abstract: Methods, systems and apparatus which resample a primal mesh signal composed of primal points associated with primal mesh vertices of a primal mesh connectivity of a primal mesh producing a dual mesh signal composed of dual points associated with primal mesh faces of said primal mesh connectivity. The dual points are computed by minimizing a quadratic energy function. The quadratic energy function is composed of a sum of square terms. The invention also constructs a dual mesh from a primal mesh, with the dual mesh signal constructed with the resampling method. It also smoothes a primal mesh signal of a primal mesh. It also constructs a primal-dual mesh from a primal mesh, with the primal-dual mesh connectivity of said primal-dual mesh constructed using a prior art method, and the primal-dual mesh signal constructed by concatenating said primal mesh signal and a dual mesh signal computed with the resampling method.

Abstract: Disclosed are an image editing user interface system and method. The system includes one or more computers with one or more graphical user interfaces, and a receiving process for receiving one or more rendered two dimensional images on the computer graphical user interface. Each two dimensional image represents reflected light from a lit three dimensional object model, and the reflective light at each point of the two dimensional image corresponds to an object point on the three dimensional object model. The system further includes a changing process for changing a portion of the two dimensional image by changing the light intensity at a set of one or more points on the two dimensional image. The change in light intensity at the set of points causes a change in the three dimensional model to correspond to the change in the light intensity.

Abstract: Methods and apparatus solving problems of polygonal approximations of isosurfaces extracted from uniformly sampled volumes increasing in size due to the availability of higher resolution imaging techniques. The large number of primitives represented hinders the interactive exploration of the dataset. Examples of methods are provided for adaptive isosurface extraction that are generally easy to implement and allows the user to decide the degree of adaptivity as well as the choice of isosurface extraction algorithm. The extraction of the isosurface is optimized by warping the volume. In a warped volume, areas of importance (e.g. containing significant details) are inflated while unimportant ones are contracted. Once the volume is warped, any extraction algorithm can be applied. The extracted mesh is subsequently unwarped such that the warped areas are rescaled to their initial proportions. The resulting isosurface is represented by a mesh that is more densely sampled in regions decided as important.

Abstract: The present invention smoothes a spherical graph signal composed of spherical signal points associated with graph vertices of a graph producing a smoothed spherical graph signal composed of smoothed spherical signal points. Each smoothed spherical signal point is computed by multiplying a vertex rotation matrix by the corresponding spherical signal point. The vertex rotation matrix is computed as a weighted average of neighbor rotation matrices using a local parameterization of the group of rotations. The present invention also filters anisotropically a graph signal composed signal points associated with graph vertices of a graph producing a filtered graph signal composed of filtered signal points. Each filtered signal point is computed as a weighted average of signal points corresponding to the corresponding graph vertices and neighbor graph vertices with neighbor weight matrices. The present invention also denoises the vertex positions of a polygon mesh without tangential drift.

Abstract: Methods, systems and apparatus which resample a primal mesh signal composed of primal points associated with primal mesh vertices of a primal mesh connectivity of a primal mesh producing a dual mesh signal composed of dual points associated with primal mesh faces of said primal mesh connectivity. The dual points are computed by minimizing a quadratic energy function. The quadratic energy function is composed of a sum of square terms. The invention also constructs a dual mesh from a primal mesh, with the dual mesh signal constructed with the resampling method. It also smoothes a primal mesh signal of a primal mesh. It also constructs a primal-dual mesh from a primal mesh, with the primal-dual mesh connectivity of said primal-dual mesh constructed using a prior art method, and the primal-dual mesh signal constructed by concatenating said primal mesh signal and a dual mesh signal computed with the resampling method.