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:
May. 23, 1995
Filed:
May. 13, 1993
Shaw-Min Lei, Tinton Falls, NJ (US);
Bell Communications Research, Inc., Livingston, NJ (US);
Abstract
Method and system are provided for efficient, multiplication-free arithmetic coding wherein data which represents an alphabet of source symbols is compressed and decompressed in a data transmission system. Multiplications are replaced with single shift-and-add operation using a suitable shift register wherein a multiplier has at most two bits. The shift-and-add operation approximates the width of a new subinterval within a predetermined interval. This approximation is a function of both the width of a current subinterval and a total count of source symbols in a statistical source model. In this way, an adaptive model can be accommodated as well as a fixed model for the statistics of the source symbols. In one embodiment, the multiplier is preferably determined by a table look-up having a small number of entries and which can be easily implemented by hardware or software.