Results on the parallel complexity of Lempel-Ziv data compression suggest that the sliding window method is more suitable than the LZW technique on shared memory parallel machines. When instead we address the practical goal of designing distributed algorithms with low communication cost, sliding window compression does not seem to guarantee robustness if we scale up the system. The possibility ...

Data processing lower bounds on the expected distortion are derived in the finite–alphabet semi–deterministic setting, where the source produces a deterministic, individual sequence, but the channel model is probabilistic, and the decoder is subjected to various kinds of limitations, e.g., decoders implementable by finite–state machines, with or without counters, and with or without a restricti...

The complexity of the mobility tracking problem in a cellular environment has been characterized under an information-theoretic framework. Shannon’s entropy measure is identified as a basis for comparing user mobility models. By building and maintaining a dictionary of individual user’s path updates (as opposed to the widely used location updates), the proposed adaptive on-line algorithm can le...

In current interframe video compression systems, the encoder performs predictive coding to exploit the similarities of successive frames. The Wyner-Ziv Theorem on source coding with side information available only at the decoder suggests that an asymmetric video codec, where individual frames are encoded separately, but decoded conditionally (given temporally adjacent frames) could achieve simi...

Scalable Wyner-Ziv video coding is desirable, especially for mobile devices with limited computational resources and bandwidth. However, the conventional bit-plane representation used in hybrid video coding does not work well in the scenario of Wyner-Ziv coding. As we know, the bit-plane representation is closely related to the quantization. In this paper, a new bit-plane representation with op...

Estimating the entropy of finite strings has applications in areas such as event detection, similarity measurement or in the performance assessment of compression algorithms. This report compares a variety of computable information measures for finite strings that may be used in entropy estimation. These include Shannon’s n-block entropy, the three variants of the Lempel-Ziv production complexi...

Simple and fast decoding is one of the main advantages of LZ77-type text encoding used in many popular file compressors such as gzip and 7zip. With the recent introduction of external memory algorithms for Lempel–Ziv factorization there is a need for external memory LZ77 decoding but the standard algorithm makes random accesses to the text and cannot be trivially modified for external memory co...

We study the hypothesis of information panspermia assigned recently among possible solutions of the Fermi paradox (“where are the aliens?”). It suggests that the expenses of alien signaling can be significantly reduced, if their messages contain compressed information. To this end we consider universal compression and decoding mechanisms (e.g. the Lempel-Ziv-Welch algorithm) that can reveal non...

An efficient hybrid distributed video coding (HDVC) scheme combining residual coding, SW-SPIHT coding and intra-mode decision technology is proposed to offer good rate-distortion performance and low-complexity encoding. The scheme adopts the waveletdomain Wyner-Ziv codec to compress the residual frame between the current frame and its reference frame. An intra-mode decision based on the tempora...

OBJECTIVE Considering the increasing use of complexity estimates in neuropsychiatric populations, a normative study is critical to define the 'normal' behaviour of brain oscillatory complexity across the life span. METHOD This study examines changes in resting-state magnetoencephalogram (MEG) complexity - quantified with the Lempel-Ziv complexity (LZC) algorithm - due to age and gender in a l...