Abstract: A plurality of rows of tiles is defined in a graphics display field comprising a plurality of rows of pixels, each tile including pixels from at least two rows of pixels. Occlusion flags for respective tiles of a row of tiles for a graphics primitive are set based on whether respective representative depth values for the tiles of the row of tiles meet an occlusion criterion. Pixels in rows of pixels corresponding to the row of tiles are processed for the graphics primitive in a row-by-row manner responsive to the occlusion flags. The processing may include processing rows of pixels in the row of tiles using a zig-zag traversal algorithm.

Abstract: A method and a device for generating a pixel value from a plurality of sample values being generated from a plurality of sample points. The method comprises generating a plurality of sample values; and weighting said plurality of sample values for determining said pixel value. Each sample value is generated from one of a plurality of candidate sample points within a sample region. The sample region is positioned at a corner of two intersecting borders of the pixel. The size of the sample region is smaller than the size of the pixel. The device is arranged to carry out the method according to the invention.

Abstract: A computer graphics processor (20,50) and a method for rendering a three-dimensional image on a display screen. The computer graphics processor (20,50) comprises a rasterizer (23,53) configured to perform pixel traversal of a primitive after projection of the primitive. Furthermore, the rasterizer (23,53) is configured to perform the pixel traversal of a first primitive for a plurality of views prior to performing pixel traversal of a next primitive for one or several views.

Abstract: A compressor for compressing a block of feature vectors representing a feature associated with image elements, includes electronic circuitry for determining the distribution of the feature vectors, electronic circuitry for transforming each point pattern in a predetermined set of point patterns to fit the determined distribution, and a selector for selecting a transformed point pattern that best fits the determined distribution. Furthermore, an encoder represents the block of feature vectors by an identifier identifying the selected point pattern in the set of point patterns, parameters representing the transformation associated with the selected point pattern, and an index for each feature vector representing the nearest point in the transformed selected point pattern.

Abstract: The invention is applied to image processing schemes by providing at least one auxiliary block processing mode in addition to the standard default block processing mode of the scheme. An image to be decoded is divided into a number of image blocks (800) having multiple image elements (810). These blocks (800) are individually compressed by means of a default compressing mode or an auxiliary compressing mode, depending on which mode that results in a smallest error metric. A portion (980) of the resulting compressed block (900) is used to discriminate between the two modes. In the auxiliary mode, the remaining payload portion (990) of the compressed block (900) can be used for encoding purposes, whereas the default mode can in addition utilize the discriminating portion (980).

Abstract: An image encoding and decoding scheme operable according two different modes depending on properties of the processed image is disclosed. In the encoding, an image is decomposed into image blocks (600) comprising image elements (610). The blocks (600) are compressed into block representations (700A, 700B) according to one of two compression modes. A block representation (700A; 700B) comprises two codewords (720A, 730A; 720B, 730B) representing properties of the image elements (610) in the block (600) and a sequence (740A; 740B) of image element associated indices indicative of one of the codewords (720B, 730B) or a property representation generated based on a codeword (730A). The block representation (700A; 700B) also includes a mode index representing the mode, according to which the block representation (700A; 700B) was compressed. This mode index can be provided before, during or after generation of the codewords (720A, 730A; 720B, 730B) and index sequence (740A; 740B).

Abstract: An alpha image encoding and decoding scheme operable according two different modes is disclosed. In the encoding, an alpha image is decomposed into alpha image blocks (600) comprising image elements (610). The blocks (600) are compressed into block representations (700) according to one of the two compression modes. A block representation (700) comprises a color codeword (720), an intensity codeword (730), an alpha codeword (740) and a sequence (750) of image element associated indices indicative of one of the codewords (730, 740). The compression and decompression mode to use for a block (600) is determined based on the alpha codeword (740). In a high alpha-resolution mode, the index sequence (750) comprises alpha indices selecting one of the quantized alpha values (740A, 740B) of the alpha codeword (740) and intensity indices selecting an intensity modifier from a modifier set represented by the intensity codeword (730).

Abstract: A block (300) of image elements (310) is compressed by determining multiple base vectors (510, 520, 530, 540) based on the feature vectors (312) associated with the image elements. Additional vectors (560, 570) are calculated based on defined pairs of neighboring base vectors (510, 520, 530, 540). A vector among the base vectors (510, 520, 530, 540) and the additional vectors (560, 570) is selected as representation of the feature vector (312) of an image element (310). An identifier (550) associated with selected vector is assigned to the image element (310) and included in the compressed block (500) which also comprises representations of the determined base vectors (510, 520, 530, 540).

Abstract: A block (300) of image elements (310) is compressed by identifying a base vector (460) based on normalized feature vectors (312) of the block (300). If a position-determining coordinate (420) of the base vector (460) is present inside a defined selection section (530) of feature vector space (500), the block (300) is compressed according to a default mode and an auxiliary mode to get a default and auxiliary compressed block (600), respectively. The compressed block (600) resulting in smallest compression error is selected. If the auxiliary mode is selected, the position-determining coordinate (420) is mapped to get a mapped coordinate (425) present outside the representable normalization portion (510) of vector space (500). The auxiliary compressed block (600) comprises a representation of this mapped coordinate (425).

Abstract: In an image-encoding scheme, an input image is decomposed into several image blocks (600) comprising multiple image elements (610), e.g. pixels or texels. The image blocks (600) are then encoded into encoded block representations (700). Such a block representation (700) comprises a color codeword (710), an intensity codeword (720) and a sequence (730) of intensity representations. The color codeword (710) is a representation of the colors of the image elements (610) of the block (600). The intensity codeword (720) is a representation of a set of multiple intensity modifiers for modifying the intensity of the image elements (610) in the block (600). The representation sequence (730) includes an intensity representation for each image element (610) in the block (600), where a representation identifies one of intensity modifiers in the intensity modifier set.

Abstract: A pixel is textured by storing a first texel reference value, a second texel reference value, and texel mapping values where each texel mapping value represents a k-tuple of (ternary) references to the first texel reference value, the second texel reference value and a third texel reference value to thereby represent a block of texels. A pixel value for the pixel is generated from the stored texel values and the pixel is displayed responsive to the generated pixel value. In some embodiments, respective pluralities of texel reference values and texel mapping values that map thereto are stored for respective ones of a plurality of overlapping blocks of texels. In further embodiments, a first mipmap value for a pixel is bilinearly interpolated from the retrieved texel values for the set of nearest neighbor texels. A second mipmap value for the pixel is generated by averaging the retrieved texel values for the set of nearest neighbor texels.

Abstract: A sampling pattern covering an array of pixels for use in an anti-aliasing system is disclosed where each pixel has a pattern of sample points at the edges of the pixel. Moreover is the sample point pattern of each pixel a mirror image and different from the pattern of a directly neighboring pixel.

Abstract: A method, system, and article of manufacture for reducing aliasing. A method in accordance with one embodiment sampling a pixel of an image at a plurality of pixel sample points to produce a corresponding plurality of pixel sample values, wherein at least one of the plurality of pixel sample points is located at a predetermined displacement from a position along an edge of the pixel. The method further includes combining the plurality of pixel sample values to produce a displayed pixel value. This Abstract is provided to comply with rules requiring an Abstract that allows a searcher or other reader to quickly ascertain subject matter of the technical disclosure. This Abstract is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. 37 CFR 1.72(b).

Abstract: A plurality of rows of tiles is defined in a graphics display field comprising a plurality of rows of pixels, each tile including pixels from at least two rows of pixels. Occlusion flags for respective tiles of a row of tiles for a graphics primitive are set based on whether respective representative depth values for the tiles of the row of tiles meet an occlusion criterion. Pixels in rows of pixels corresponding to the row of tiles are processed for the graphics primitive in a row-by-row manner responsive to the occlusion flags. The processing may include processing rows of pixels in the row of tiles using a zig-zag traversal algorithm.

Abstract: A pixel is textured by storing a first texel reference value, a second texel reference value, and texel mapping values where each texel mapping value represents a k-tuple of (ternary) references to the first texel reference value, the second texel reference value and a third texel reference value to thereby represent a block of texels. A pixel value for the pixel is generated from the stored texel values and the pixel is displayed responsive to the generated pixel value. In some embodiments, respective pluralities of texel reference values and texel mapping values that map thereto are stored for respective ones of a plurality of overlapping blocks of texels. In further embodiments, a first mipmap value for a pixel is bilinearly interpolated from the retrieved texel values for the set of nearest neighbor texels. A second mipmap value for the pixel is generated by averaging the retrieved texel values for the set of nearest neighbor texels.