Patent ID: 8669889
Filing Date: 2014-03-11
Classification: H03M,H04B,H04L

Abstract:
1. A computer program product for compressing an input data stream to produce a compressed output data stream, the computer program product comprising a computer readable storage medium having computer readable program code embodied therein that is executed to perform operations, the operations comprising: determining whether a number of consecutive data units in the input data stream match the number of consecutive data units in a history buffer of previously received data units in the input data stream; in response to determining that the number of consecutive data units in the input data stream match the number of consecutive data units in the history buffer, generating a copy pointer symbol indicating the copy pointer symbol referencing previously received data units in the history buffer and indicating a location of a start of the consecutive data units in the history buffer; determining from a variable length code table an encoding of the number, wherein the variable length code table has: a first prefix of one bit which indicates that a next following one bit represents two or three data units; a second prefix of two bits which indicates that a next following one bit represents four or five data units; a third prefix of three bits which indicates that a next following one bit represents six or seven data units, and a fourth prefix of four bits which indicates that a next following one bit represents eight or nine data units; indicating in the generated copy pointer symbol the determined encoding of the number; and outputting the copy pointer symbol in the compressed output data stream.