Abstract: A “texture generator” uses an inverse texture synthesis solution that runs in the opposite direction to traditional forward synthesis techniques to construct 2D texture compactions for use by a graphics processing unit (GPU) of a computer system. These small 2D texture compactions generally summarize an original globally variant texture or image, and are used to reconstruct the original texture or image, or to re-synthesize new textures or images under user-supplied constraints. In various embodiments, the texture generator uses the texture compaction to provide real-time synthesis of globally variant textures on a GPU, where texture memory is generally too small for large textures. Further, the texture generator provides an optimization framework for inverse texture synthesis which ensures that each input region is properly encoded in the output compaction. In addition, the texture generator also computes orientation fields for anisotropic textures containing both low- and high-frequency regions.

Abstract: A software-implemented transform and lighting module and pipeline designed and optimized for embedded platforms (such as mobile computing devices). The transform and lighting module and pipeline includes a number of features that make it well-suited for use on embedded devices. These features include a single streamline branched architecture that allows efficient processing on a CPU of an embedded device and saves computational time. This architecture is facilitated by use of a vertex cache that stores vertices as needed to avoid duplication in processing of the vertices. A culling feature culls vertices before lighting instead of lighting all vertices. A back face culling technique examines each of the vertices to determines whether a back face of a triangle is formed. If so, then the vertex is culled. A second technique involved determining whether a vertex is outside of one view frustum clip plane. If so, then the vertex is culled.

Abstract: The present soft shadowing technique pre-computes visibility of blockers using a log of a spherical harmonic visibility function. These logs can then be accumulated and exponentiated in real-time to yield the product visibility vector over all the blockers. The product visibility vector is combined with the light intensity and surface reflectance to determine shading at a receiver point in a computer-generated scene.

Abstract: User interactive methods of determining vertex correspondence between boundaries or curves on objects to be merged is provided. One method relates to projecting a boundary of one object onto a second object to determine a merging curve, along which the two objects will be joined. Another method includes projecting a first object onto a plane to form a planar curve. The planar curve is then mapped to a second object to form a merging curve. Still another method includes interactively selecting corresponding key vertices on different objects to form a merging curve. A system presented that can use one or more of the methods of determining correspondence between boundaries. A merged object can be generated from the merging curve using a mesh solver, such as a Poisson or non-Poisson mesh solver.

Abstract: Rendering of a partially translucent object is performed using a set of parameter maps derived from data measuring reflectance and transmittance of light received at the surface of the partially translucent object. Data is captured from an actual object being modeled, rather than estimated based on internal structure and composition. Parameter maps relating albedo, thickness variation, and specular intensity and roughness are stored as textures to facilitate rendering. In addition, realistic illumination from high energy sources such as sunlight is effected by separating light into low frequency and high frequency components. Low frequency components are rendered by precomputed radiance transfer. High frequency components, which are not modeled well by precomputed radiance transfer, are modeled using a light visibility convolution integral to generate light visibility maps for positions of the high frequency light source.

Abstract: The present surface detail rendering technique provides an efficient technique for applying a mesostructure to a macrostructure for an object that minimizes the amount of memory required for pre-computed data. A leap texture is pre-computed for a mesostructure by classifying each voxel in the mesostructure geometry and assigning a value in the leap texture based upon the classification. The value in the leap texture represents a distance to jump along a ray cast in any view direction when a model is decorated with the mesostructure geometry.

Abstract: A non-linear beam tracing technique that supports full non-linear beam tracing effects including multiple reflections and refractions for computer graphics applications. The technique introduces non-linear beam tracing to render non-linear ray tracing effects such as curved mirror reflection, refraction, caustics, and shadows. Beams are allowed to be non-linear where rays within the same beam are not parallel or do not intersect at a single point. Such is the case when a primary beam bounces off of a surface and spawns one or more secondary rays or beams. Secondary beams can be rendered in a similar manner to primary rays or beams via polygon streaming. Beyond smooth ray bundles, the technique can also be applied to incoherent ray bundles which is useful for rendering bump mapped surfaces.

Abstract: An exemplary method includes providing image data for an illuminated physical sample of a heterogeneous translucent material, determining one or more material properties of the material based in part on a diffusion equation where one of the material properties is a diffusion coefficient for diffusion of radiation in the material and where the determining includes a regularization term for the diffusion coefficient, mapping the one or more material properties to a virtual object volume, assigning virtual illumination conditions to the virtual object volume, and rendering the virtual object volume using the virtual illumination conditions as a boundary condition for a system of diffusion equations of the virtual object volume. Other methods, devices and systems are also disclosed.

Abstract: An exemplary computer-implementable method includes providing a computer-generated object wherein the object has characteristics, emitting a computer-generated particle, determining if the particle interacts with the object and, if the particle interacts with the object, altering one or more of the characteristic of the object wherein the altering simulates weathering or aging of the object. Various other exemplary techniques are also disclosed.

Abstract: A system and process for determining the vignetting function of an image and using the function to correct for the vignetting is presented. The image can be any arbitrary image and no other images are required. The system and process is designed to handle both textured and untextured segments in order to maximize the use of available information. To extract vignetting information from an image, segmentation techniques are employed that locate image segments with reliable data for vignetting estimation. Within each image segment, the system and process capitalizes on frequency characteristics and physical properties of vignetting to distinguish it from other sources of intensity variation. The vignetting data acquired from segments are weighted according to a presented reliability measure to promote robustness in estimation.

Abstract: A computer implemented method for generating a representation of structure for use in rendering a synthesized image is provided. The representation is a view-dependent displacement mapping that represents displacements along a viewing direction. This view dependency allows the representation to be used to determine self shadows as well as shading, occlusion and silhouettes when used during rendering for synthesis.

Abstract: A method and apparatus improve the efficiency of simulating a virtual environment by filtering information about the virtual environment on a group basis instead of a character basis. The filtered information is sent to each client associated with a character in the group.

Abstract: Pre-computed shadow fields are described. In one aspect, shadow fields for multiple entities are pre-computed. The shadow fields are pre-computed independent of scene configuration. The multiple entities include at least one occluding object and at least one light source. A pre-computed shadow field for a light source indicates radiance from the light source. A pre-computed shadow field for an occluding object indicates occlusion of radiance from the at least one light source.

Abstract: Radiometric calibration of an image capture device (e.g., a digital camera) using a single image is described. The single image may be a color image or a grayscale image. The calibration identifies and analyzes edge pixels of the image that correspond to an edge between two colors or grayscale levels of a scene. Intensity distributions of intensities measured from the single image are then analyzed. An inverse response function for the image capture device is determined based on the intensity distributions. For a color image, the radiometric calibration involves calculating an inverse response function that maps measured blended colors of edge pixels and the associated measured component colors into linear distributions. For a grayscale image, the radiometric calibration involves deriving an inverse response function that maps non-uniform histograms of measured intensities into uniform distributions of calibrated intensities.

Abstract: An apparatus and method provide for providing an output image from an input image. The input image may contain at least one portion that does not display certain desired information of the image, such as texture information. The desired information may be obtained from a second portion of the input image and applied to the at least one portion that does not contain the texture information or contains a diminished amount of the texture information. Also, at least one characteristic of the second portion of the input image may not be applied to the at least one portion such as illumination information. In another example, the input image may be decomposed into multiple parts such as a high frequency and a low frequency component. Each component may be hallucinated individually or independently and combined to form the output image.

Abstract: A real-time algorithm for rendering an inhomogeneous scattering medium such as fog is described. An input media animation is represented as a sequence of density fields, each of which is decomposed into a weighted sum of a set of radial basis functions (RBFs) such as Gaussians. The algorithm computes airlight and surface reflectance of the inhomogeneous scattering medium. Several approximations are taken which lead to analytical solutions of quantities such as an optical depth integrations and single scattering integrations, and a reduced number of integrations that need to be calculated. The resultant algorithm is able to render inhomogeneous media including their shadowing and scattering effects in real time. The algorithm may be adopted for a variety of light sources including point lights and environmental lights.

Abstract: A real-time algorithm for rendering of an inhomogeneous scattering media such as smoke under dynamic low-frequency environment lighting is described. An input media animation is represented as a sequence of density fields, each of which is decompressed into a weighted sum of a set of radial basis functions (RBFs) and an optional residual field. Source radiances from single and optionally multiple scattering are directly computed at only the RBF centers and then approximated at other points in the volume using an RBF-based interpolation. Using the computed source radiances, a ray marching technique using slice-based integration of radiance along each viewing ray is performed to render the final image. During the ray marching process, the residual field may be compensated back into the radiance integral to generate images of higher detail.

Abstract: A real-time algorithm for rendering of an inhomogeneous scattering media such as smoke under dynamic low-frequency environment lighting is described. An input media animation is represented as a sequence of density fields, each of which is represented by an approximate model density field and a residual density field. The algorithm uses the approximate model density field to compute an approximate source radiance, and further computes an effective exitant radiance by compositing the approximate source radiance using a compositing methods such as ray marching. During the compositing process (e.g., ray marching), the residual field is compensated back into the radiance integral to generate images of higher detail.

Abstract: A real-time algorithm for rendering of an inhomogeneous scattering medium such as fog with a surface object immersed therein is described. An input media animation is represented as a sequence of density fields. The algorithm computes surface reflectance of the surface object in the inhomogeneous scattering medium. The algorithm may also compute airlight of the inhomogeneous scattering medium. Several approximations are taken which lead to analytical solutions of quantities such as optical depth integrations and single scattering integrations, and a reduced number of integrations that need to be calculated. The resultant algorithm is able to render inhomogeneous media including their shadowing and scattering effects in the real time. The algorithm may be adopted for a variety of light sources including point lights and environmental lights.

Abstract: A real-time algorithm for rendering of an inhomogeneous scattering media such as smoke under dynamic low-frequency environment lighting is described. An input media animation is represented as a sequence of density fields, each of which is decomposed into a weighted sum of a set of radial basis functions (RBFs) and an optional residual field. Source radiances from single and optionally multiple scattering are directly computed at only the RBF centers and then approximated at other points in the volume using an RBF-based interpolation. Unique approximation techniques are introduced in the computational algorithms to simplify and speed up the computation of source radiance contributed by single and multiple scattering. Using the computed source radiances, a ray marching technique using slice-based integration of radiance along each viewing ray may be performed to render the final image.