HIGH SPEED COSINE TRANSFORM

摘要

A discrete transform cosine circuit utilizing symmetries of the cosine matrix of coefficients to allow all multiplications to be done by "constant multipliers" comprising combinations of look-up tables and adders. Transform coefficients are developed by dividing each into a sequence of blocks of preselected size, the information in the blocks is sorted to develop a specific order and the reordered blocks are applied seriatim to a first one-dimensional cosine transform circuit 20 employing the constant multipliers. The output of the first cosine transform circuit is applied to a transposing memory 30 and then to a second cosine transform circuit 40 that also employs "constant multipliers". <IMAGE>