Joy S Thomas

US Patent:

57292280, Mar 17, 1998

Filed:

Jul 6, 1995

Appl. No.:

8/498948

Inventors:

Peter Anthony Franaszek - Mt. Kisco NY
John Timothy Robinson - Yorktown Heights NY
Joy Aloysius Thomas - White Plains NY

Assignee:

International Business Machines Corp. - Armonk NY

International Classification:

H03M 700

US Classification:

341106

Abstract:

A method and apparatus for compressing a block of data using a shared dictionary. Data to be compressed is divided into subblocks which are each provided to a respective compressor in a plurality of compressors. The compressors cooperatively construct a dynamic compression dictionary and compress the subblocks in parallel using the dictionary. Compressed subblocks output by the compressors are concatenated to form a compressed block.

US Patent:

56359314, Jun 3, 1997

Filed:

Jun 2, 1994

Appl. No.:

8/253047

Inventors:

Peter A. Franaszek - Mount Kisco NY
Joy A. Thomas - White Plains NY
Pantelis G. Tsoucas - Mount Kisco NY

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

H03M 730

US Classification:

341 51

Abstract:

A system and method for compressing or predicting data information received within an input stream, wherein contextual information is utilized in the selection of dictionaries for encoding or predicting of a next phrase within the information stream. The present invention utilizes contextual information in conjunction with dictionary-based Lempel-Ziv compression processes.

US Patent:

58700366, Feb 9, 1999

Filed:

Feb 24, 1995

Appl. No.:

8/393967

Inventors:

Peter Anthony Franaszek - Mt. Kisco NY
John Timothy Robinson - Yorktown Heights NY
Joy Aloysius Thomas - White Plains NY

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

H03M 700

US Classification:

341 51

Abstract:

A system and method for compressing and decompressing data using a plurality of data compression mechanisms. Representative samples of each block of data are tested to select an appropriate one of the data compression mechanisms to apply to the block. The block is then compressed using the selected one of the mechanisms and the compressed block is provided with an identifier of the selected mechanism. For decompression, the identifier is examined to select an appropriate one of the data decompression mechanisms to apply to the block. The block is then decompressed using the selected one of the mechanisms.