Abstract: A method (300) and arrangement for LZ1 compression of a data string where multiple input symbols are compared in parallel with the history buffer by: holding in an input buffer (140) a first sequence of bytes of the data string; holding in a history buffer (110, 120) a second sequence of bytes of the data string; comparing (170), in matrix comparison means coupled to the input buffer and the history buffer and having a plurality of rows and columns of comparison units (200), bytes held in the input buffer with bytes held in the history buffer, bytes of the history buffer being coupled to diagonally displaced comparison units in the matrix comparison means; detecting (150) in each of the rows the column in which a largest number of consecutive byte matches has occurred at the comparison unit in that row and preceding comparison units in the same column; and encoding (160) as a token a sequence of matched bytes detected in the step of detecting (150).

Abstract: A method (300) and arrangement for LZ1 compression of a data string where multiple input symbols are compared in parallel with the history buffer by: holding in an input buffer (140) a first sequence of bytes of the data string; holding in a history buffer (110, 120) a second sequence of bytes of the data string; comparing (170), in matrix comparison means coupled to the input buffer and the history buffer and having a plurality of rows and columns of comparison units (200), bytes held in the input buffer with bytes held in the history buffer, bytes of the history buffer being coupled to diagonally displaced comparison units in the matrix comparison means; detecting (150) in each of the rows the column in which a largest number of consecutive byte matches has occurred at the comparison unit in that row and preceding comparison units in the same column; and encoding (160) as a token a sequence of matched bytes detected in the step of detecting (150).

Abstract: An apparatus for performing data compression is disclosed. A circuit (640) within a comparison unit (400) of a comparison matrix (170) performs LZ1 compression of a data string by comparing bytes held in an input buffer (140) with bytes held in a history buffer (110, 120). A group of logic gate stages (720, 730, 740, 750) is connected in series with each other. Each of the logic gate stages produces a carry value that is passed to one of the output of the comparison unit and another logic gate stages. The product of the number stages in the logic gate stages and the number logic gates in each of the logic gate stages is less than the number of logic gates required for an equivalent circuit having a single logic circuit stage.