Abstract: A method is provided for calculating edge normals when transforming 3D geometric data (e.g., polygon mesh data) to voxel data, which includes four steps. First, each geometric unit (e.g., each polygon) in the 3D geometric data is mapped to a voxel grid. Second, edge voxels are detected in the voxel grid. As used herein, an edge voxel means a voxel forming an edge of an object to be rendered. Third, for each edge voxel, one or more normals of the one or more geometric units that intersect with that edge voxel are calculated and stored. Fourth, for each edge voxel, an edge normal is obtained by combining (e.g., equal-weight-averaging) the one or more normals stored in association with that edge voxel.

Abstract: A system and method for improved antialiasing in video processing is described herein. Embodiments include multiple video processors (VPUs) in a system. Each VPU performs some combination of pixel sampling and pixel center sampling (also referred to as multisampling and supersampling). Each VPU performs sampling on the same pixels or pixel centers, but each VPU creates samples positioned differently from the other VPUs corresponding samples. The VPUs each output frame data that has been multisampled and/or supersampled into a compositor that composites the frame data to produce an antialiased rendered frame. The antialiased rendered frame has an effectively doubled antialiasing factor.

Abstract: The present invention relates to a technology of appropriately improving image resolution. According to an image signal processing method of the present invention, an input video signal contains an image signal whose pixel size is converted at a specified magnification scale. The input image signal is used to calculate sampling frequencies for image signals before and after the pixel size conversion. A ratio of sampling frequencies before and after the pixel size conversion is used to determine the specified magnification scale. A sampling phase for the image signal before the pixel size conversion is calculated from the input image signal after the pixel size conversion. A sampling carrier for the image signal before the pixel size conversion is generated from the sampling frequency and the sampling phase both before the pixel size conversion.

Abstract: An apparatus for smoothed aliasing on a two-dimensional plane includes a data input unit for receiving at least one piece of data input by a user, a graphic engine processing unit for generating a quadrangle including a form of the at least one piece of data and differently applying transparency to at least one transparent area included in the quadrangle, and a display unit for displaying the at least one piece of data processed by the graphic engine processing unit.

Abstract: In an implementation, a pixel is selected from a target digital image. Multiple candidate pixels, from one or more digital images, are evaluated based on values of the multiple candidate pixels. For the selected pixel, a corresponding set of pixels is determined from the multiple candidate pixels based on the evaluations of the multiple candidate pixels and on whether a predetermined threshold number of pixels have been included in the corresponding set. Further for the selected pixel, a substitute value is determined based on the values of the pixels in the corresponding set of pixels. Various implementations described provide adaptive pixel-based spatio-temporal filtering of images or video to reduce film grain or noise. Implementations may achieve an “even” amount of noise reduction at each pixel while preserving as much picture detail as possible by, for example, averaging each pixel with a constant number, N, of temporally and/or spatially correlated pixels.

Abstract: A graphics processing platform includes a rasteriser 50 that receives primitives representing an image to be displayed for processing. The rasteriser 50 determines which sets of sampling points of the image include sampling points that are covered by a given primitive, and then generates a fragment for rendering for each set of sampling points found to include a sampling point that is covered by the primitive and passes those fragments to a renderer 51 for rendering. The renderer 51 carries out rendering operations on the fragments that it receives, and stores the rendered fragment data in tile buffers 52. The rendered fragment data is stored in multiple copies in the appropriate sample positions in the tile buffers 52, so as to provide a separate set of fragment data for each individual sample position taken of the image. The data from the tile buffers 52 is input to a downsampling unit 53, and hence output to a frame buffer 54 of a display device 55 for display.

Abstract: A method and apparatus for performing multisampling-based antialiasing in a system that includes first and second graphics processing unit (GPUs) that reduces the amount of data transferred between the GPUs and improves the efficiency with which such data is transferred. The first GPU renders a first version of a frame using a first multisampling pattern and the second GPU renders a second version of a frame in the second GPU using a second multisampling pattern. The second GPU identifies non-edge pixels in the second version of the frame. The pixels in the first version of the frame are then combined with only those pixels in the second version of the frame that have not been identified as non-edge pixels to generate a combined frame.

Abstract: An image filtering method, apparatus and system, wherein the method comprising the steps of detecting at least one portion of an edge, wherein the portion of the edge provides an indication that ringing artifact are probable; subjecting at least one portion of a pixel, related to the at least a portion of the edge, to a low pass filter to produce a filtered pixel; and blending the filtered pixel with a value relating to the filter prior to filtering to produce a filtered image.

Abstract: Surfaces without a global surface coordinate system are divided into surface regions having local surface coordinate systems to enable the caching of surface attribute values. Surface attribute functions are evaluated to determine surface attribute values for the surface regions. A surface attribute value for a surface region may include contributions from two or more adjacent surfaces. A multiresolution cache stores surface attribute values at different resolution levels for surface regions of one or more surfaces, which may be discontiguous. Surface attribute values for a surface are retrieved from the multiresolution cache by dividing the surface into surface regions at a desired resolution level and selecting a corresponding resolution level of the multiresolution cache. One or more cached surface attribute values are retrieved for each surface region.

Abstract: A liquid crystal drive device includes: a frame memory retaining image information of a second frame immediately preceding a first frame; a first calculator calculating a first difference between image information of the first frame and the image information of the second frame; an edge enhancement processor performing edge enhancement processing of the first frame for each of pixels of the first frame and outputting edge enhancement image information; a selector selecting and outputting the edge enhancement image information or image information of the first frame; a second calculator calculating a second difference between an output of the selector and the image information of the second frame; an enhancement coefficient calculator multiplying an output of the second calculator by an enhancement correction coefficient; and a third calculator calculating sum information by adding together an output of the enhancement coefficient calculator and the image information of the second frame.

Abstract: A digital image composition method is adapted to eliminate a ghost image produced by a digital image-capturing apparatus due to handshakes in shooting. The method includes the steps. In a pre-shooting process, a base image and a comparison image are respectively captured. A base pixel is selected from the base image, and a core window is set with the base pixel at the center. A comparison pixel is selected from the comparison image, and a search window is set with the comparison pixel at the center. Each area of the search window is compared through the core window, and an absolute error sum value between the base image and the comparison image is calculated. It is determined how to change the brightness of the base pixel according to the normalized region difference value. The above steps are repeated to adjust each pixel in the base image.

Abstract: The invention relates to a processing method of a sequence of images comprising image points each of which is associated with a color component. The method comprises a processing step of at least one image of the sequence from reference images, the processing step being adapted to reduce the flicker effects. According to the invention, the reference images are selected according to the following stages: calculate, for at least one image part of each of the images of the sequence, the mean value of the colour component, the mean value being associated with the image, and a first selection step to select from the mean values a first series of reference images forming a subset of the sequence.

Abstract: A method of processing image data comprises receiving input signals for specifying red, green and blue colors of the pixels of a display, performing a per-pixel low pass filtering of the input signals, the low pass filtering function being dependent on the chrominance variation between adjacent pixels, and providing the filtered output signals for use in driving the pixels of a display. This method essentially measures the chrominance variation of the incoming signal, in the form of the color change frequency, and depending on this variation, adaptively low-pass filters the incoming signal. This can be in such a way that the chrominance resolution of the outgoing signal is below the maximum chrominance resolution of the intended display, without errors in the average color of a small group of pixels.

Abstract: Described are a video graphics system, graphics processor, and methods for rendering three-dimensional objects. A buffer is partitioned into tiles of pixels. Each pixel of each tile includes at least one sample. A primitive is received and determined to cover fully one of the tiles. A section of the primitive that maps to the fully covered tile is tested to determine if every sample within the fully covered tile is to undergo the same stencil operation. The stencil operation is performed on the fully covered tile in the buffer if every sample within the fully covered tile is to undergo the same stencil operation.

Abstract: The invention provides tools and techniques for clone brushing pixels in an image while accounting for inconsistencies in apparent depth and orientation within the image. The techniques do not require any depth information to be present in the image, and the data structure of the image is preserved. The techniques allow for color compensation between source and destination regions. A snapping technique is also provided to facilitate increased accuracy in selecting source and destination positions.

Abstract: The invention relates to a visualization apparatus (1) for visualizing an image data set. The visualization apparatus (1) comprises an image data set providing unit (2) for providing the image data set, a differential property determination unit (5) for determining local differential properties for different regions of the image data set, an assigning unit (6) for assigning visualization properties to the different regions of the image data set depending on the determined local differential properties, wherein a visualization property defines the visualization of a region, to which the visualization property is assigned, and a display unit (7) for displaying the visualization properties assigned to the different regions of the image data set. By displaying the visualization properties assigned to the different regions of the image data set different objects can visually be separated from each other without requiring large computational costs.

Abstract: A method for reducing image noise with edge tracking comprises receiving input of an object image data for conversion and a size data of a matrix, namely, a conversion area of the image data; calculating a statistical difference value between each pixel of the image data and a pixel adjacent to the pixel in a predetermined direction and calculating edge map data obtained from the calculation in each predetermined direction; and converting an object pixel for conversion of the image data using calculation pixels located in the matrix of the image data, wherein the conversion step outputs main calculation pixels, namely, calculation pixels having a statistical difference value below a predetermined level with a value of the object pixel among the calculation pixels based on the edge map data, and converts the object pixel using a statistical calculation value of the main calculation pixels.

Abstract: A floating point rasterization and frame buffer in a computer system graphics program. The rasterization, fog, lighting, texturing, blending, and antialiasing processes operate on floating point values. In one embodiment, a 16-bit floating point format consisting of one sign bit, ten mantissa bits, and five exponent bits (s10e5), is used to optimize the range and precision afforded by the 16 available bits of information. In other embodiments, the floating point format can be defined in the manner preferred in order to achieve a desired range and precision of the data stored in the frame buffer. The final floating point values corresponding to pixel attributes are stored in a frame buffer and eventually read and drawn for display. The graphics program can operate directly on the data in the frame buffer without losing any of the desired range and precision of the data.

Abstract: Various technologies and techniques are disclosed for improving output rendering in anti-aliased rendering scenarios. A pixel snapping mode of operation is turned on and off to improve output rendering. When the system detects that an animation has started, the pixel snapping mode is turned off, and when the system detects that the animation has stopped, the pixel snapping mode is resumed. Techniques for providing a smooth transition can be used when turning pixel snapping on. One example of a transition technique includes turning off pixel snapping when an animation begins by immediately lowering the strength of an effect of the pixel snapping mode to zero. Another example includes turning on pixel snapping when the animation finishes by raising the strength of the effect of the pixel snapping mode over a period of time until the strength is full strength.

Abstract: A system for correcting image characteristic data from a plurality of pixels comprises at least one field programmable gate array (FPGA), a lookup table, and a correction module. The FPGA may include a plurality of configurable logic elements and a plurality of configurable storage elements. The lookup table may be accessible by the FPGA and may store a plurality of correction components associated with each pixel, including a gain value, an offset value, and a bad pixel value. The correction module may be formed from the configurable logic elements and configurable storage elements and may receive the characteristic data and the correction components. The correction module may generate corrected data for each characteristic data by utilizing the gain value, the offset value, and the bad pixel value.

Abstract: A CPU generates an image by performing inverse projection transformation for an input image by using an inverse matrix of a matrix which enlarges a size of the input image. When a position A on the input image is transformed into a position B on the generated image by the inverse projection transformation, the CPU obtains a ratio of a distance between pixels around the position B to a distance between pixels around the position A. The CPU calculates filter coefficients for a low-pass filter using a product of a Nyquist frequency of the input image and the ratio as a cutoff frequency. The CPU obtains a sum of results obtained by multiplying pixel values of pixels in a pixel array including the position A in the input image by the filter coefficients, as a pixel value at the position A in an image having undergone filter processing.

Abstract: Multiprocessor graphics systems support distributed antialiasing. In one embodiment, two (or more) graphics processors each render a version of the same image, with a difference in the sampling location (or locations) used for each pixel. A display head combines corresponding pixels generated by different graphics processors to produce an antialiased image. This distributed antialiasing technique can be scaled to any number of graphics processors.

Abstract: A method for selecting a desired color from a screen display using a color selection tool that may appear as an eyedropper. Rather than independently choosing pixels or a matrix of pixels, the user blends a color by selecting pixels using a mouse cursor. In response, the color of each selected pixel is incrementally blended into the current color at a constant rate. That is, each selected pixel is blended with the current color according to a constant blending factor. In this manner, the current color changes at a constant rate with the contribution of each successive pixel. This approach allows the user to gradually blend colors from the screen display, much as a painter would gradually mix colors on a palette.

Abstract: Systems and methods are disclosed for processing image data to provide adjusted pixel information that achieves smoothed output discontinuities. In one exemplary embodiment, there is provided a method of processing image data including analyzing first display information including pixel data indicative of pixel display on a graphical user interface, detecting one or more ramp steps in the pixel data, and assigning, in association with random number generation and/or threshold setting functionality, a carry possibility for a pixel adjacent the one or more ramp steps. Other exemplary implementations may include generating second display information included adjusted pixel data for pixels adjacent the ramp steps. Consistent with certain implementations, the second display information may include pixel values adjusted according to the carry possibility in one or both of the temporal domain and/or spatial domain.

Abstract: A system and method for generating an image on a display. The display includes a plurality of pixels from a vector description of a scene. The data is sampled from the vector description to provide data samples at locations defined in relation to the pixels. For example, the locations may include a first and second locations at the edges of the pixels, a third location at the corner of the pixels and a fourth location at the center of the pixels. The data samples are stored in a buffer and processed for each of the pixels to give an averaged data value. The image is then generated the image on the display by applying the averaged data value to each of the pixels. The calculation of the weighted averaged color value is repeated for each of the fragments in the buffer until all of the samples have been averaged.

Abstract: Embodiments of the present invention comprise methods and systems for brightness preservation using a smoothed gain map.

Abstract: Methods of rendering a view of a scene include steps that specify quality levels of anti-aliasing and texture filtering for predetermined regions of a display, or selected objects within the scene, or both. Methods of processing data for display include steps adapted to process portions of the image according to selected or predetermined anti-aliasing and texture filtering quality levels. Graphics processing equipment includes hardware or software adapted to perform non-uniform anti-aliasing of images according to specified criteria.

Abstract: An image data update apparatus that can highlight a component with maintaining an appearance of an image to which anti-aliasing is applied and with suppressing increase in processing load is provided. When periodically changing a color arrangement of a traffic congestion line bordered using a color of black and displayed on a map image, only a central portion of the traffic congestion line is changed. Each time the color arrangement is changed, anti-aliasing is applied only to a boundary between the central portion and bordering portion but not to a boundary with a background map image.

Abstract: A method for enabling near unity scaling of printer video data to provide compensation for paper shrinkage caused during duplex printing. To achieve high quality image output, near neighbor interpolation may be used at very high resolutions. However, the insertion of extra interpolated subpixels may cause an edge transition to be shifted away from its original subpixel location with respect to an applied anti-aliasing rendering screen thereby causing ragged edges. The method aligns the edge position and the anti-aliasing rendering screen by applying a cyclical rotation of the screen.

Abstract: A method aligns a character to a sampling grid of an image. An original uniform width path that traces a skeleton of the character is specified by input pen commands having original coordinates. The width of the original path is rounded to a nearest integer to produce a hinted width. The original path is traversed using the input pen commands to identify segments of the path. The segments are stored in an array. Hinted coordinates are determined for each segment in the array. The array is sorted, and a directed acyclic graph (DAG) is constructed. Collisions between the segments are resolved using the sorted array, the DAG, and the width of the hinted path. The segments are fitted to the sampling grid, and the result is stored in output pen commands, thereby aligning the skeleton of the character to the sampling grid.

Abstract: A circuit arrangement and method provide a hybrid rendering architecture capable of interfacing a streaming geometry frontend with a physical rendering backend using a dynamic accelerated data structure (ADS) generator. The dynamic ADS generator effectively parallelizes the generation of the ADS, such that an ADS may be built using a plurality of parallel threads of execution. By doing so, both the frontend and backend rendering processes are amendable to parallelization, and enabling if so desired real time rendering using physical rendering techniques such as ray tracing and photon mapping. Furthermore, streaming geometry frontends such as OpenGL and DirectX compatible frontends can readily be adapted for use with physical rendering backends, thereby enabling developers to continue to develop with raster-based API's, yet still obtain the benefits of physical rendering techniques.

Abstract: The display of a Windows Desktop is modified using one or more processors (e.g. CPUs and/or GPUs) that re-direct drawing of the Desktop to mirrored swap chain buffers; modify the contents of the a front buffer of the mirrored swap chain buffers; and draw the Desktop using the modified contents of the front buffer of the mirrored swap chain buffers. To modify the displayed Desktop, Windows needs to draw into these mirrored swap chains instead of its own. To accomplish this, all Direct3D functions that use a swap chain are hooked so that they return the mirrored swap chain, and any function that uses the contents of the swap chain are hooked. Basically any function that takes a Direct3D surface or texture is hooked and the respective item from the mirrored swap chains is returned if it is in the mirrored swap chain data structures.

Abstract: A display control device used to govern non-content regions in a display space, and selectively determine data for display in the non-content regions is described. The display control device can identify the non-content regions, and determine types of data that can be filled in the non-content regions. Once determined, the fill data can be presented in the non-content regions concurrently with an image frame.

Abstract: Systems and methods are provided for improved filtering and correcting of glyphs on a GPU. The computational intensity required for filtering and/or rendering can be reduced by pre-calculating some or all of the calculations needed for converting coverage data into corrected pixel values. Additional efficiencies may be realized in some embodiments by transferring data from a CPU to a GPU in an improved format. The improvements can be realized in a variety of graphics formats.

Abstract: The invention relates to a method for enhancing color resolution and particularly for obtaining bit resolution in a display using a bits per pixel system frame buffer. The invention uses logic to create intermediate pixel values between bpp color values. The invention proposes to store the image in the system frame buffer always with a fixed number of bits and using Error Diffusion Dither. Then a postprocessing filter is provided to provide the enhanced color resolution using a greater number of bits per pixel as accepted by the display means. The invention also relates to a device exploiting the method.

Abstract: Ink rendering techniques are described. In an implementation, an input is recognized by one or more modules that are executable on one or more processors of a computing device as an ink stroke to be rendered by a display device of the computing device. The ink stroke is built by the one or more modules using a strip of triangles and the strip of triangles is sent to a graphics processing unit to render the ink stroke.

Abstract: Systems and methods for modifying the number of texture samples used to produce an anisotropically filtered texture mapped pixel may improve texture mapping performance. When the number of texture samples is reduced, fewer texels are read and fewer filtering computations are needed to produce a texture value for an anisotropic footprint. The number of texture samples is reduced based on the mip map level weight. The number of texture samples may also be modified using specific parameters for the coarse and/or fine mip map levels. The spacing between the texture samples along the major axis of anisotropy may be modified to improve image quality or texture cache performance.

Abstract: Anti-aliased output based on a scene comprising a plurality of objects may be generated. In one embodiment, a number of samples for an anti-aliasing operation is determined. For each of the samples: each of the objects may be translated in space according to jitter values; the objects may be multiplied by a fractional alpha value for the respective sample; a fractional alpha value stored in a buffer may be modified by a transparency value for each transparent object; and the objects may be rendered to the buffer by blending the objects with existing contents of the buffer. The fractional alpha values may vary from sample to sample. In one embodiment, the plurality of objects comprises one or more opaque objects and one or more transparent objects. In one embodiment, the objects may be rendered directly to a screen buffer.

Abstract: The edge evaluation technique, in accordance with one embodiment of the present technology, includes determining a number of edges of a given primitive to be evaluated. The technique also includes sequencing evaluation of a first edge by a first edge evaluation circuit and a second edge by a second edge evaluation circuit during a first clock cycle. The technique further includes sequencing evaluation of a third edge by the first edge evaluation circuit and a fourth edge by the second edge evaluation circuit during a second clock cycle if three or more edges are to be evaluated.

Abstract: A method and apparatus for reducing color error bands occurring due to the abrupt difference in brightness between sub-pixels. In the method of displaying an image signal of an apparatus for displaying the image signal, the apparatus includes a plurality of pixels each having at least two sub-pixels, and the method includes detecting pixels that belong to an edge of an input image, changing pixel values of the sub-pixels constituting the pixels belonging to the edge, and driving a display in accordance with the new pixel value.

Abstract: Provided is a display method used for a display device that displays a design image and a pickup image in a superimposing manner, including: a distortion correction process of correcting distortion of the pickup image; an alignment process of aligning a position of the design image and a position of the pickup image; and a display process of displaying the design image and the pickup image in the superimposing manner. In the distortion correction process, the distortion of the pickup image is corrected so that a quadrangle formed by connecting four points on the pickup image becomes a rectangle in parallel with a vertical axis and a horizontal axis, the four points specified on the pickup image corresponding to four points on the design image which are connected to form a rectangle in parallel with the vertical axis and the horizontal axis.

Abstract: An image output apparatus is provided with an image conversion unit for converting image data into an output image of intermediate gradation using a line screen for forming pixel points in stripes, an element angle storing unit for storing the angle information of line segments of the image data, a jaggy judging unit for judging whether or not jaggies will appear on the outline of the output image based on the angle information of the line segments stored in the element angle storing unit, and a screen angle setting unit for substantially changing the screen angle of the line screen if jaggies are judged to appear by the jaggy judging unit.

Abstract: One embodiment of the present invention sets forth a technique for improving antialiasing quality, while minimizing performance degradation, by adaptively selecting between multisampling and supersampling on a per pixel basis. The resulting performance may be generally comparable to multisampling. At the same time, however, the resulting quality may be generally comparable to supersampling. The antialiasing technique disclosed herein determines whether to use multisampling or supersampling on a particular pixel being rendered, based on the specific coverage of the associated geometry primitive. Because many pixel centers are covered by a geometry primitive, a statistical performance advantage is gained when pixels in a rendered image can be generating using multisampling rather than supersampling. The cases where pixel centers are not covered tend to be less frequent, but are very significant to image quality. High image quality is maintained by rendering these cases using supersampling.

Abstract: A drawing apparatus includes a reception unit, a first holding unit and a drawing processing unit. The reception unit receives graphic information. The first holding unit holds a plurality of first data which is a part of the graphic information received by the reception unit, in association with identification numbers assigned to the first data. The drawing processing unit draws a graphic on the basis of the first data held in the first holding unit. The drawing processing unit uses the plurality of the first data in a same task to draw the graphic. The reception unit records the identification numbers of the first data and a synchronization flag in order of reception. The synchronization flag is set for the first data received first among the plurality of first data processed by the same task in the drawing processing unit.

Abstract: An image processing apparatus for sequentially generating rendering data of a plurality of images composing a moving image, comprising a velocity vector detecting unit for detecting a velocity vector of a block image in an image in accordance with the rendering data based on rendering basic data used for the generation of the rendering data and a control unit for selectively performing, for each of the block images of the rendering data and based on a velocity vector generated by the velocity vector detecting unit, subsampling processing for generating only part of the pixel data in the pixel data corresponding to the block image based on the rendering basic data and non-subsampling processing for generating all pixel data corresponding to the block image based on the rendering basic data to thereby generate the rendering data.

Abstract: Systems and methods used for bilinear texture filtering may also be used to perform font filtering. Font data stored as a texture is read from memory in blocks that are coarsely aligned. Font alignment units may be used to provide a finely aligned region of the font data within a font filter footprint. The finely aligned region is then filtered using bilinear filtering to produce font coverage information representing a grayscale value for a pixel. Using existing bilinear filtering engines in conjunction with font alignment and sample units reduces the need for having a specific engine to perform each of the font filtering operations, possibly saving die area in a graphics system.

Abstract: A content-adaptive overdrive system and method, for a display panel, include a frame difference device and an overdrive device. The frame difference device generates a frame difference map according to a current frame and a previous frame. The frame difference map includes a number of flags respectively indicating similarity between corresponding pixels or blocks of the current frame and the previous frame. The overdrive device adaptively performs an overdrive function based on the frame difference map, the current frame, the previous frame and an overdrive lookup table, hence resulting in an overdrived frame.

Abstract: Methods and apparatuses for anti-aliasing scan conversion. In one aspect of the invention, an exemplary method to scan convert an image on a data processing system includes: sampling the image in a first direction to generate first signals for points along a second line in a second direction using a closed form solution for a convolution integral with a first kernel; and weighting the first signals for the points according to a second kernel in the second direction to generate a second signal for a pixel. In one example according to this aspect, the closed form solution is tabulated in a look up table. After entries are looked up from the look up table according to the image along a first line in the first direction on a first point of the points, the entries are combined to generate one of the first signals for the first point.

Abstract: Methods, systems, and apparatus, including computer program products, feature receiving an image mask where the image mask identifies a first opacity value of pixels in a raster image. The first opacity value ranges between a value representing foreground and a value representing background. Each pixel in the image has a color. A first boundary pixel is identified in the image. A second opacity value for the first boundary pixel is determined using a first local color model of opacity. The first local color model of opacity is determined based on the colors of the pixels in the image within a local neighborhood of the first boundary pixel.

Abstract: Methods of modeling a three-dimensional surface structure include partitioning three-dimensional object data into regions of a Morse complex and generating a feature skeleton having a plurality of smooth edges and a plurality of vertices separating the regions of the Morse complex. Operations are also performed to thicken the feature skeleton by replacing the plurality of smooth edges with corresponding pairs of curves that locate longitudinal boundaries of transitions between primary regions of the feature skeleton. The thickening operations may also include replacing each of the plurality of vertices with a corresponding loop of edges, using setback-type vertex blends.