Patent ID: 6871208
Filing Date: 2005-03-22
Classification: G06F

Abstract:
1. A device for partial calculation of a 2-D inverse discrete cosine transform (IDCT), on a set of input data values, based on a coefficient matrix essentially as follows where u e and u 0 are even and odd indexed values in the set of input data values C e T and C 0 T are coefficient sub-matrices, v p is a vector of sums of output data values, and v n is a vector of differences of output data values, the device comprising: one or more input lines; and one or more adder networks, coupled with the input lines, including logic to pre-add said input data values to generate operands and to calculate v logic to combine values of vectors v wherein said adder networks include carry save adders interconnected to produce intermediate sums and carries and further connected to an additional adder to produce a sum; wherein the set of input data values consists of eight values, u wherein successive sets of input data values constitute an 8×8 matrix of values, further comprising logic for presenting successive sets of input data values one set at a time, coupled between the input lines and the adder networks.