Fast gapped variants for Lempel–Ziv–Welch compression

Variants of classical data compression paradigms by Ziv, Lempel, and Welch are proposed in which the phrases used in compression are selected among suitably chosen strings of intermittently solid and wild characters produced by the autocorrelation of the sourcestring. Adaptations and extensions of the classical ZL78 paradigm as implemented by Welch are developed along these lines, and they are easily seen to be susceptible of simple linear time implementation. Both lossy and lossless schemata are considered, and preliminary analyses of performance are attempted.