We explore the possibility of using multiple processors to improve the encoding and decoding times of Lempel–Ziv schemes. A new layout of the processors, based on a full binary tree, is suggested and it is shown how LZSS and LZW can be adapted to take advantage of such parallel architectures. The layout is then generalized to higher order trees. Experimental results show an improvement in compr...

This paper presents an experiment with human subjects concerning the vague spatial relation ‘near’ in environmental space. After the topic is introduced and relevant previous work surveyed, the experiment is described. Three approaches to experimental analysis are presented and discussed: nearness neighbourhoods as regions with broad boundaries, fuzzy nearness and distance measures, and four-va...

This paper considers the problem of data compression for dependent quantum systems. It is the second in a series under the same title which began with [6] and continues with [12]. As in [6], we are interested in Lempel–Ziv encoding for quantum Gibbs ensembles. Here, we consider the canonical ideal lattice Boseand Fermi-ensembles. We prove that as in the case of the grand canonical ensemble, the...

This paper presents conditional versions of Lempel-Ziv (LZ) algorithm for settings where compressor and decompressor have access to the same side information. We propose a fixed-length-parsing LZ algorithm with side information, motivated by the Willems algorithm, and prove the optimality for any stationary processes. In addition, we suggest strategies to improve the algorithm which lower the d...

This paper clari es two variable-toxed length codes which achieve optimum large deviations performance of empirical compression ratio. One is Lempel-Ziv code with xed number of phrases, and the other is an arithmetic code with xed codeword length. It is shown that Lempel-Ziv code is asymptotically optimum in the above sense, for the class of nite-alphabet and nite-state sources, and that the ar...

We introduce a new approach to LZ77 factorization that uses O(n/d) words of working space and O(dn) time for any d ≥ 1 (for polylogarithmic alphabet sizes). We also describe carefully engineered implementations of alternative approaches to lightweight LZ77 factorization. Extensive experiments show that the new algorithm is superior in most cases, particularly at the lowest memory levels and for...

Kleene’s strong three-valued logic extends naturally to a four-valued logic proposed by Belnap. We introduce a guard connective into Belnap’s logic and consider a few of its properties. Then we show that by using it four-valued analogs of Kleene’s weak three-valued logic, and the asymmetric logic of Lisp are also available. We propose an extension of these ideas to the family of distributive bi...

Lempel-Ziv (LZ) is a popular lossless data compression algorithm that produces good compression performance, but suffers from relatively slow processing speed. This paper proposes an enhanced version of the Lempel-Ziv algorithm, through incorporation of a neural pre-processor in the popular predictor-encoder implementation. It is found that in addition to the known dramatic performance increase...

Lempel–Ziv Welch (LZW) algorithm is a well-known powerful data compression algorithm created by Abraham Lempel, Jacob Ziv, and Terry Welch. The algorithm is designed to be fast to implement but is not usually optimal because it performs only limited analysis of the data. A modified LZW algorithm on source coding will be proposed in this paper to improve the compression efficiency of the existin...