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: A method and system for performing full-scene anti-aliasing for an image through a technique of rotating and unrotating rasterization of a scene and rendering a resulting image. A scene is rasterized at a first angle relative to a first coordinate system to generate a plurality of pixels, which are then applied to a polygon surface that is rendered at a second angle equal to the inverse of the first angle. Thus, the resulting image is re-oriented with respect to the first coordinate system.

Abstract: A method of minimizing color aliasing artifacts from a color digital image having color pixels is disclosed. The method includes providing luminance and chrominance signals from the color digital image; using the luminance and chrominance signals to compute neighborhoods of pixels which are to be processed and wherein such neighborhoods of pixels are substantially bounded by pixels defining edges; producing low frequency chrominance signals in response to the chrominance signals; using the low frequency chrominance signals and the computed neighborhood of pixels to produce noise-cleaned chrominance signals; upsampling the noise-cleaned chrominance signals to produce upsampled noise-cleaned chrominance signals; and using the luminance signals and the upsampled noise-cleaned chrominance signals to provide a color digital image having reduced color aliasing artifacts.

Abstract: A system and method for providing antialiasing of a graphical image on a display is disclosed. The graphical image is generated from data describing at least one object. The display includes a plurality of pixels. The at least one object includes a plurality of fragments. A portion of the plurality of fragments intersects a pixel of the plurality of pixels. Each of the plurality of fragments including an indication of a portion of a corresponding pixel that is intersected. The system and method include providing at least one active region for the pixel. The at least one active region intersects a first portion of the pixel. The method and system also include providing at least one new region. A first portion of the at least one new region indicates where in the pixel the at least one active region and the fragment intersect. A second portion of the at least one new region indicates where in the pixel the at least one active region and the fragment do not intersect.

Abstract: A method and apparatus antialias a region of a two-dimensional distance field representing an object. The two-dimensional distance field is partitioned into cells where each cell includes a method for reconstructing the two-dimensional distance field within the cell. A set of cells of the two-dimensional distance field associated with the region is identified and a set of pixels associated with the region is located. For each pixel, a set of components is specified. For each component, a distance is determined from the set of cells and then mapped to the antialiased intensity of the component of the pixel.

Abstract: A method, apparatus, and system for combining a first signal and a second signal is disclosed, e.g., superimposing graphic signals on video signals. A first signal containing an object and an object indicator, e.g., a chroma key background color or a separate signal indicating presence or absence of an object, is used to determine weighting values for pixels at the edges of the object. The weighting values are then used to blend the first signal and a second signal at the edges of the object to minimize sharp transitions, thereby minimizing aliasing.

Abstract: A method and apparatus determine an antialiased intensity of a component of a pixel from a two-dimensional distance field representing an object. A set of sample points in the two-dimensional distance field is associated with the component of the pixel. A distance is determined from the two-dimensional distance field and the set of sample points and then mapped to the antialiased intensity of the component of the pixel.

Abstract: A method and apparatus determine an antialiased intensity of a component of a pixel. A set of objects is represented by a set of two-dimensional distance fields. For each distance field, a corresponding set of sample points is associated with the component and a corresponding distance is determined using the corresponding set of sample points. The corresponding distances are combined to determine a combined distance that is mapped to the antialiased intensity of the component of the pixel.

Abstract: A method and apparatus antialias a region of a set of objects. The set of objects is represented by a set of two-dimensional distance fields. Each distance field is partitioned into cells, where each cell is associated with a method for reconstructing the distance field within the cell. For each distance field, a set of cells associated with the region is identified. A set of pixels associated with the region is located and a set of components is specified for each pixel. For each component of each pixel, a corresponding distance for the component is determined for each distance field using the corresponding set of cells and the corresponding distances are combined to determine a combined distance. The combined distance is mapped to an antialiased intensity of the component of the pixel.

Abstract: A method renders a region of a composite glyph. The composite glyph is defined by a set of elements. A set of two-dimensional distance fields is generated using the set of elements, where each two-dimensional distance field is partitioned into cells and each cell includes a method for reconstructing the corresponding two-dimensional distance field within the cell. A composition of the set of two-dimensional distance fields represents the composite glyph. The region of the composite glyph is then rendered using the set of two-dimensional distance fields.

Abstract: A method renders a region of a composite glyph. The composite glyph is defined by a set of elements. A set of two-dimensional distance fields is generated using the set of elements, where a composition of the set of two-dimensional distance fields represents the composite glyph. The region of the composite glyph is then rendered using the set of two-dimensional distance fields.

Abstract: A filtering method and filtering system is applied to an edge orientation map obtained from an edge direction detection system in order to keep accurate edge directions and filter out false edges or edges with wrong directions. If an edge direction does not have a certain minimum length, then that direction is filtered out and a default direction is provided. Additional assurances can be obtained by insuring that the edge direction has a certain minimum width. If an edge direction does not have the minimum width, then that edge direction is filtered out and the default direction is provided. A direction smoother can be applied to the directions in the edge orientation map to smooth the changing of neighboring edge directions. This process is found to be effective in improving the visual quality of an image that is interpolated based on edge directions.

Abstract: The embodiments of the present invention are a method and apparatus to perform anti-aliasing using multi-sampling on a non-power-of-two pixel grid. Using the present invention with 6 sample multisampling gives the same visual antialiasing quality as 8 samples using a prior art technique but uses less memory. A non-power-of-two equally spaced sample from a conventional grid of size N×N, where N is 12 can be chosen using the present invention. A scan conversion to determine the set of pixels covered by a polygon is performed in two parts. According to one embodiment, the present invention can multiply and divide by “N” in order to multisample an image using samples per pixel chosen from a N×N sub-sample grid, where “N” is not necessarily a power of 2. The present invention performs the divide by “N” step, where the step is achieved using a quick divide by 3 or 12 technique.

Abstract: An image processing device includes a data zone expansion circuit and an image processing circuit. The data zone expansion circuit receives input data, increases a number of data bits of said input data, and provides data with the increased number of data bits. The image processing circuit performs image processing on said data with the increased number of data bits.

Abstract: In one embodiment, selecting auxiliary screen regions to activate in rendering a straight line segment on a screen of a computer monitor, wherein the straight line segment comprises points defined by an algebraic expression equal to zero, wherein the expression is expressed as a first constant multiplied by a x-axis value plus a second constant multiplied by a y-axis value plus a third constant, wherein the straight line segment has a width.

Abstract: A method for computing normalized minor axis distance to an ideal line for variable-width line antialiasing. The method involves performing line primitive setup by constructing a triangle from the two line vertices and a third vertex biased from a line endpoint by the line width/2. Normalized barycentric coordinates are computed for this triangle, which together can be used for primitive attribute interpolation. One of the barycentric coordinates contains the normalized minor-axis distance to the ideal line, which can be used with a slope-correct coverage table to compute coverage. Because the minor-axis distance is normalized, the coverage value is independent of line width.

Abstract: An improved method and system for generating real-time anti-aliased polygon images is disclosed. Fixed orientation multipixel structures contain multiple regions, each with independent color and depth value, and an edge position. Regions are constructed for polygon edge pixels which are then merged with current region values, producing new multipixel structures. Multipixel structures are compressed to single color values before the pixel buffer is displayed.

Abstract: A filtering engine may read samples from a sample buffer and spatially filter (e.g., convolve) the samples to generate pixels. The pixels may have a high dynamic range of luminance. Thus, the filtering engine may apply automatic gain control and/or dynamic range compression on pixel luminance or pixel color. A rendering engine may generate the samples in response to received graphics data and store the samples in the sample buffer. A sample may include one or more data fields which represent color (or intensity) information. The data field may include exponent information (e.g., an amplification control bit) and a mantissa. The exponent information may determine an extent to which the mantissa is amplified (e.g., left shifted) in the filtering engine.

Abstract: The shape processor is a rendering module that may be used to stream graphical objects having a predefined format into a frame buffer or a physical display. Documents to be rendered by the shape processor may be decomposed into primitive graphical objects and passed to the shape processor, which may in turn compose the objects for display. Composed objects are then blended into current video data on an object by object basis.

Abstract: A computer graphics system that utilizes a super-sampled sample buffer and a sample-to-pixel calculation unit for refreshing the display. The graphics system may have a graphics processor, a super-sampled sample buffer, and a sample-to-pixel calculation unit. The graphics processor renders samples into the sample buffer at computed positions or locations in the sample buffer. The graphics system may utilize a window ID that specifies attributes of pixels on a per object basis. The window ID may specify one or more of a sample mode, filter type, color attributes, or source attributes. The sample mode may include single sample per pixel mode and multiple samples per pixel mode. In implementing a single sample per pixel mode, the graphics system may be further operable to generate a single sample per pixel for certain windows of the screen in order to, for example, provide backwards compatibility with legacy systems with no multi-sampling support.

Abstract: A method, apparatus, and system are provided for rendering of photorealistic computer graphics images. According to one embodiment, an image is partitioned into regions, each of the regions having a discontinuity edge, a boundary, edge pixels along the boundary, and remaining pixels, and orientation of the discontinuity edge is estimated by computing a direction of least discrepancy within each of the regions by evaluating the edge pixels along the boundary of each of the regions.

Abstract: A system, method and computer program product are provided for two-sided stencil testing during graphics processing. Initially, primitives are received to be processed in a graphics processing pipeline. In use, it is then determined whether the graphics processing pipeline is operating with same-sided stencil testing enabled. If same-sided stencil testing is not enabled, the primitives are passed without same-sided stencil testing and two-sided stencil testing. If, on other hand, same-sided stencil testing is enabled, it is determined whether the graphics processing pipeline is operating with two-sided stencil testing enabled. If the two-sided stencil testing is enabled and the same-sided stencil testing is enabled, two-sided stencil testing is performed on the primitives. If, on the other hand, the two-sided stencil testing is disabled and the same-sided stencil testing is enabled, same-sided stencil testing is performed on the primitives.

Abstract: An image processing device detects the correlation between a pixel to be removed in thinning pixel blocks generated by using a delay in horizontal and vertical directions and an adjacent pixel. The device then determines a coefficient corresponding to the correlation. From the pixel to be removed and the adjacent pixel, pixel data is generated by using a predetermined calculation equation. Thinning and reduction of each pixel block in the horizontal and vertical directions thus occurs.

Abstract: A method and system for providing antialiasing of a graphical image on a display from data describing at least one object is disclosed. The display includes a plurality of pixels. The method and system include providing a plurality of fragments for the at least one object. A portion of the plurality of fragments intersects a pixel of the plurality of pixels. Each of the plurality of fragments includes a depth value, a slope of the depth value, and an indication of a portion of a corresponding pixel that is intersected. The method and system include calculating a plurality of subpixel depth values for a fragment of the plurality of fragments. The plurality of subpixel depth values is calculated using the depth value and the slope of the depth value of the fragment. The method and system include determining whether to store a portion of the fragment based on the plurality of subpixel depth values for the fragment and the indication of the extent the corresponding pixel is intersected by the fragment.

Abstract: A method of smoothing data to reduce or remove noise while preserving edge information in the data selects an output point in the data, identifies the most homogeneous neighborhood around the selected output point and outputs a corrected value for the selected output point based upon data points in the identified neighborhood.

Abstract: A system and method for generating random coverage masks for rendering images with transparent objects. The system uses shuffle tables for addresses of a pixel to index into a transparency table and to obtain a transparency mask, which is then ANDed with a coverage mask to obtain a new coverage mask.

Abstract: Systems and methods are provided for providing anti-aliasing by introducing a falloff area around a graphics object to be rendered. The falloff area is shaded, using Gouraud shading or texture mapping to reduce the aliasing effects of the graphics object. The outside edge of the falloff area is set to be fully transparent, and the inside edge to an opacity matching the outer edge of the graphics object being rendered. To counteract bloating effects, the graphics object is shrunk by half the width of the falloff area. While the width of the falloff area may vary, generally, the width of the falloff area stays constant. In one embodiment, this width corresponds to the edge or diagonal of the square area mapped to each pixel.

Abstract: A method of reducing ringing artifacts in image data that has been filtered with a high frequency emphasis filter. For each filtered data value, a local variance is calculated from data values at neighboring filter taps. This variance is compared to a threshold, and if the threshold is exceeded, the filtered data value is limited between local minimum and maximum values. A method of reducing noise, also using the local variance, is also described.

Abstract: The present invention discloses methods and apparatus for processing anti-aliased digital images. Specifically, the present invention describes methods and apparatus where anti-aliased images of a given pixel resolution are transformed to high resolution binary images, binary operations such as template matching are performed on the high resolution images, and then the high resolution images are transformed to anti-aliased images of a predetermined pixel resolution.

Abstract: A method, system, and computer program product for filtering textures applied to a surface of a computer generated object permits an application program running on a computer system to significantly increase the graphics capabilities and performance of the computer. Rendering data for a pixel of the object is received from the application program, and a first and second set of texture coordinates is generated. Next, the first and second sets of texture coordinates are used to obtain a first and second texture sample from a texture image. The first and second texture samples are then blended together to produce a texture sample having a greater degree of filtering. This produced texture sample having a higher degree of filtering is stored in a frame buffer for subsequent display.

Abstract: The system and method reduces aliasing which is formed by the patterns that are introduced by the halftone screens used in the printer. The system and method provides halftone-specific anti-alias filters for obtaining optimal effective resolution in printed images. A method of reducing aliasing in a digital image includes providing a digital image; selecting a halftone screen for halftoning the digital image, wherein the halftone screen has a directional component associated with it; filtering the digital image with an antialiasing filter, the antialiasing filter having been designed to have a directional frequency response that is optimized for the directional component of the selected halftone screen; and halftoning the filtered digital image.

Abstract: A method and system thereof for processing data in a computer graphics system. More specifically, an anti-aliasing buffer architecture for processing fragments in a computer graphics system is described. When a new fragment for a particular pixel location is received, the fragment stack for that pixel location is read from fragment memory. The new fragment is appended to the fragment stack, and the resultant fragment stack is written back to fragment memory before it is processed in a computer graphics pipeline. Fragments stored in fragment memory are not sorted according to their distance from the view plane (the z-dimension); instead, z-ordered depth sorting is performed in the computer graphics pipeline. Using an occlude command, occluded (blocked) fragments can be deleted from the fragment stack before the fragment stack is passed to the computer graphics pipeline. The computer graphics pipeline calculates a pixel color for each pixel location.

Abstract: A video processing method for preparing an anti-aliased foreground image for display over an image background comprises the steps of:

Abstract: A system and method for providing antialiasing of a graphical image on a display is disclosed. The graphical image is generated from data describing at least one object. The display includes a plurality of pixels. The at least one object includes a plurality of fragments. A portion of the plurality of fragments intersects a pixel of the plurality of pixels. Each of the plurality of fragments including an indication of a portion of a corresponding pixel that is intersected. The system and method include providing at least one active region for the pixel. The at least one active region intersects a first portion of the pixel. The method and system also include providing at least one new region. A first portion of the at least one new region indicates where in the pixel the at least one active region and the fragment intersect. A second portion of the at least one new region indicates where in the pixel the at least one active region and the fragment do not intersect.

Abstract: An alpha channel layer is generated by an opacity value that is assigned to each pixel of the image layer. The opacity value is represented by N bits/pixel and is generated by the expression j/(2N−1) where j is a value that represents the binary value of the N bits. When the image is to be rendered on the new background, the background layer is combined with the image and alpha channel layers to generate the updated, final RGB values for each pixel. These updated RGB components are expressed as Rfinal=R(p)*O+R(pbackground)*(1−O), Gfinal=G(p)*O+G(pbackground)*(1−O), and Bfinal=B(p)*O+B(pbackground)*(1−O) where O is the opacity value of image pixel p and pbackground is the background pixel associated with the image pixel p.

Abstract: A filtering method and filtering system is applied to an edge orientation map obtained from an edge direction detection system in order to keep accurate edge directions and filter out false edges or edges with wrong directions. If an edge direction does not have a certain minimum length, then that direction is filtered out and a default direction is provided. Additional assurances can be obtained by insuring that the edge direction has a certain minimum width. If an edge direction does not have the minimum width, then that edge direction is filtered out and the default direction is provided. A direction smoother can be applied to the directions in the edge orientation map to smooth the changing of neighboring edge directions. This process is found to be effective in improving the visual quality of an image that is interpolated based on edge directions.

Abstract: An integer arithmetic graphic line scan-conversion procedure sub-divides a pixel grid into a 1/N sub-pixel grid, where N is a positive integer selected to provide a desired precision. A line segment is defined by a pair of vertices relative to the sub-pixel grid. The vertices are ordered such that the line segment is in one of the first and the second quadrants, depending upon the slope of the line segment. An integer estimate is made of the slope of the line segment relative to the sub-pixel grid. The scan progresses along a major axis at pixel intervals, while best-fit integer projections of the line segment are made along an orthogonal axis relative to the sub-pixel grid. A resulting array of integer line-scan points relative to the sub-pixel grid are used to adjust color and brightness attributes of display pixels, and the resulting adjusted pixels are output to a display device to create an image of the scanned line segment. In a preferred embodiment, N is a positive power of 2.

Abstract: The present invention is related to a computer graphics rendering system, method and program product for drawing a plurality of pixels in parallel.

Abstract: A graphics system may be configured to render anti-aliased dots in terms of samples and to generate pixels by filtering the samples. The pixels are supplied to one or more display devices. The means used to generate the samples may perform the computation of radial distance at positions on a grid in a rendering coordinate space, and interpolate estimates for the radial distances of samples around the dot as needed based on the radii at the grid positions.

Abstract: A system, method, and computer program product are provided for antialiasing during rendering in a graphics pipeline. Initially, a primitive of vertex data is received in a graphics pipeline. Next, a super-sampling operation is performed on the primitive of vertex data ufilizing the graphics pipeline. Further, a multi-sampling operation is performed on the primitive of vertex data utilizing the graphics pipeline.

Abstract: The present invention provides a solution to the problems of performing transformation functions on data originating in gamma space and part of systems that do not use, or are not intended to use, gamma correction schemes. The invention provides additional stages to a transform block used by a transform function. In the scheme of the invention, each input sample has a degamma function (inverse gamma) applied to it to transform it from gamma space to linear space, prior to the transform block. The degamma function is such as to approximate the transfer function of a typical monitor. After the transform operation is applied at the transform block to produce a result, a gamma function is applied to the result to return the sample to gamma space so that the output sample is ready for further processing.

Abstract: A method of blending artwork objects. In the method, user input is received selecting a first parameter setting and a second parameter setting for an effect on an object. The first parameter setting, the second parameter setting and a blend parameter setting are passed to the effect. A third parameter setting is generated in the effect from the first parameter setting, the second parameter setting and the blend parameter setting. The effect is applied to the object with the third parameter setting to generate an rendered version of the object.

Abstract: A method of reducing color aliasing artifacts from a color digital image having color pixels includes providing luminance and chrominance signals from the color digital image; using such luminance and chrominance signals to separate the image into textured and nontextured regions having boundaries; downsampling the chrominance signals and texture region mapping; producing cleaned chrominance signals in the textured regions in response to the boundaries of the textured region and chrominance signals; producing cleaned chrominance signals in the nontextured regions in response to the chrominance signals; upsampling the noise-cleaned chrominance signals; and using the luminance and upsampled noise-cleaned chrominance signals to provide a color digital image having reduced color aliasing artifacts.

Abstract: A method and system for performing full-scene anti-aliasing for an image through a technique of rotating and unrotating rasterization of a scene and rendering a resulting image. A scene is rasterized at a first angle relative to a first coordinate system to generate a plurality of pixels, which are then applied to a polygon surface that is rendered at a second angle equal to the inverse of the first angle. Thus, the resulting image is re-oriented with respect to the first coordinate system.

Abstract: A method, using a filter function, generates an anti-aliased discrete image from a continuous image including an edge. The method defines a line sample. A progressive convolution is derived from the filter function and the line sample. A pixel at a predetermined location in the discrete image is selected, and the line sample is oriented with respect to the selected pixel. A distance is measured from a point in the continuous image corresponding to the selected pixel to the edge along the oriented the line sample. The progressive convolution is evaluated at the measured distance to produce a weighted coverage value, and the weighted coverage value is associated with the pixel to anti-alias the pixel in the discrete image.

Abstract: A method and apparatus of smoothing a generalized polygon is disclosed. The method and apparatus identifies a vertex of the generalized polygon with a sharp corner and replaces the sharp corner with a rounding arc. In one embodiment, the method and apparatus draws a circle using said identified vertex as a center of said circle. The embodiment further identifies appropriate intersection points between said circle and said generalized polygon. With said intersection points identified, the embodiment ten formulates line segments between said intersection points and said vertex, and proceeds to replace said sharp corner between said intersection points with said rounding arc. Said rounding arc has said intersection points as its end points and has said formulated line segments as its tangents.

Abstract: A system for full-scene anti-aliasing and stereo three-dimensional display control. The system includes a receiving buffer, a geometry offset generator, a rendering engine, and a blending engine. The receiving buffer receives a geometry, and the geometry offset generator receives stereo parameters and FSAA parameters, calculates first and second stereo offsets according to the stereo parameters, and calculates first and second FSAA offsets according to the FSAA parameters. The rendering engine combines the first and second stereo offsets with the first FSAA offset respectively to obtain first and second new offsets, combines the first and second stereo offsets with the second FSAA offset respectively to obtain third and fourth new offsets, and re-renders the geometry according to the first, second, third, and fourth new offsets respectively, so as to obtain first, second, third, and fourth new geometry.

Abstract: One aspect of the invention is a method for normalizing a plurality of signals wherein the plurality of signals have a shared component and wherein at least one of the signals has been distorted in a nonlinear way. A distortion function is determined for at least one of the signals which is proportional to the distortion of that signal relative to at least one of the remaining signals. An inverse relative distortion function is generated for the distorted signal responsive to the distortion function that was determined for that signal. The signal is normalized by applying the inverse relative distortion function that was generated for the distorted signal.

Abstract: Disclosed are an antialiasing method and an image processing apparatus using the same, capable of high-quality image display without any significant reduction in processing speed and without any significant increase in the apparatus scale. Pixel data contains information on a subpixel mask indicative of region which a polygon occupies within a pixel. Based on data sets consisting of the subpixel masks and color data contained in the pixel data, display colors are determined on a pixel-by-pixel basis.

Abstract: A system and method is disclosed for management of sample data to enable video rate anti-aliasing convolution. Sample data may be moved simultaneously from a sample buffer to a bin scanline cache and from the bin scanline cache to an array of N2 processor-memory units (e.g. 25 for N=5). Pixel data may be convolved from an N×N sample bin array that may be approximately centered on the pixel location. Since each sample bin contains Ns/b samples, Ns/b×N2 samples may be filtered for each pixel (e.g. 400 for N=5 and Ns/b=16). Each processor-memory unit convolves the sample data for one sample bin in the N×N sample bin array and supports a variety of filter functions. Pixel data may be output to a real time video data stream.