Adaptive Trellis Encoding of Discrete-Time Sources with a Distortion Measure

Abstract

An adaptive trellis-encoding scheme, using the Viterbi algorithm for trellis search and the Kalman algorithm for adaptive adjustment, is described. The encoder is comprised of a fixed precoder and a time-varying trellis coder in tandem. The source decoder is time-varying with the time-varying part being represented by a feed forward finite-state machine (FSM). Adaptive trellis encoding requires the presence of a local FSM to monitor the adaptive encoding operation. The absence of the source signal at the decoder requires the transmission of a side-information for the mechanization of the adaptive operation of the source decoder. The transmission rate of the proposed adaptive trellis-encoding scheme is (1 + 1/Kp)/M bits per source symbol, where M is the block size which the precoder maps source symbols onto an intermediate signal set before trellis coding and Kp is the update period. Results obtained in the encoding of iid binary, autoregressive, and video sources are presented. Copyright © 1977 by The Institute of Electrical and Electronics Engineers, Inc.