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M x N DIMENSIONAL RUN LENGTH CODING

IP.com Disclosure Number: IPCOM000024823D
Original Publication Date: 1982-Apr-30
Included in the Prior Art Database: 2004-Apr-04
Document File: 2 page(s) / 42K

Publishing Venue

Xerox Disclosure Journal

Abstract

Halftone cells are divided into M x N segments which are predictively coded. The actual and predicted bit patterns of each segment are compared, and a count representing the number of successive correct predictions is accumulated. When a prediction error is made, the accumulated count is converted into a run length code. Furthermore, the actual bit pattern of the segment responsible for the prediction error is examined for conformity to any one of a plurality of statis-tically likely bit patterns. If conformity is found, a header code representing the bit pattern is generated. If, on the other hand, there is a lack of conformity, a header code indicating such a lack is generated and the raw data from the non-conforming segment is transmitted immediately after the run length code.

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XEROX DISCLOSURE JOURNAL

M x N DIMENSIONAL RUN LENGTH CODING
Henry H. Liao

Proposed Classification
U.S. C1. 358/261 Int. C1. H04n 1/00

Halftone cells are divided into M x N segments which are predictively coded. The actual and predicted bit patterns of each segment are compared, and a count representing the number of successive correct predictions is accumulated. When a prediction error is made, the accumulated count is converted into a run length code. Furthermore, the actual bit pattern of the segment responsible for the prediction error is examined for conformity to any one of a plurality of statis- tically likely bit patterns. If conformity is found, a header code representing the bit pattern is generated. If, on the other hand, there is a lack of conformity, a header code indicating such a lack is generated and the raw data from the non- conforming segment is transmitted immediately after the run length code.

Volume 7 Number 2 March/April 1982 115

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  XEROX DISCLOSURE JOURNAL Volume 7 Number 2 March/April 1982

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