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Parameter Reduction and Context Selection for Compression of Gray-Scale Images

IP.com Disclosure Number: IPCOM000043425D
Original Publication Date: 1984-Aug-01
Included in the Prior Art Database: 2005-Feb-04

Publishing Venue

IBM

Related People

Authors:
Langdon, GG Rissanen, JJ Todd, SJP [+details]

Abstract

This invention relates to a method for compressing digitized signals (event values) comprising the steps of: (a) partitioning the event values to be encoded into equivalence classes; (b) determining conditioning contexts where a partition of the event value may comprise a context component; and (c) encoding the event value by (1) the equivalence class conditioned by the context and (2) encoding the event value within the equivalence class unconditionally. Relatedly, a context component may include a partition based on a prior encoded event value. Also, the encoded event may include an error value obtained from a linear prediction model. Error is the difference between actual and predicted values.