The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 16, 1996
Filed:
Jan. 14, 1994
Jeffrey P Tobin, Corvallis, OR (US);
Hewlett-Packard Corporation, Palo Alto, CA (US);
Abstract
Data is compressed/decompressed according to the address location of data entries contained within a dictionary built in a content addressable memory 88. During data compression, character combinations which have not previously occurred within the input data stream are encoded as new data entries within the dictionary. When the character string OMEGA-K fails to match any existing dictionary entry, the address of the data entry (OMEGA) is output as a codeword representing the matched portion of the character string and OMEGA-K are stored in a new address location for later use. In compression, update circuitry 84 allows a memory search and a data write to be performed during the same clock cycle. Compressed data strings are decompressed by using the compressed data characters as addresses for link list traversal of the decompression dictionary. The data entry addressed by the data character is output if it does not require further decompression. If the data entry read from memory contains another codeword, the codeword is fed back to the address decoder as the next dictionary address.