Abstract: A trilinear texture filtering system and method that improves the locality of texture map accesses in a multum in parvo (MIP) map so as to reduce page breaks and provide improved performance. The present invention includes a texture cache having a unique addressing and accessing scheme that allows localized reads of the texture map from each of four banks in the texture cache. This is coupled with a unique texture-mapping unit that includes a first level generator, a second level generator and an interpolator. In generating the lower-resolution texture map version, the present invention filters neighboring texels from the higher-resolution version. Thus, an n×n (e.g. 2×2) square of texels at the higher-resolution level is reduced to a single texel at the lower-resolution level. This technique permits the lower-resolution level to be derived without requiring additional read operations from texture memory with potentially poor locality.

Abstract: A system for adding or subtracting numbers in signed floating point notation performs exponent and mantissa handling operations in parallel. The system includes a comparator, for determining a greater-magnitude and a lesser magnitude floating point number, operating in parallel with a selector for performing a one's complement and single-bit shift on a mantissa portion of the lesser-magnitude floating point number. The system further includes a remaining shift circuit, for determining an additional amount by which the lesser-magnitude mantissa portion should be shifted; and a shifter. The system also includes an absolute add circuit, for determining whether an absolute addition or an absolute subtraction is to be performed, and a single-bit shift circuit, for indicating whether a shift of at least one bit is required.

Abstract: An image processing system includes an image encoder system and a image decoder system that are coupled together. The image encoder system includes a block decomposer and a block encoder that are coupled together. The block encoder includes a color quantizer and a bitmap construction module. The block decomposer breaks an original image into blocks. Each block is then processed by the block encoder. Specifically, the color quantizer selects some number of base points, or codewords, that serve as reference pixel values, such as colors, from which quantized pixel values are derived. The bitmap construction module then maps each pixel colors to one of the derived quantized colors. The codewords and bitmap are output as encoded image blocks. The decoder system includes a block decoder. The block decoder includes a block type detector, one or more decoder units, and an output selector.