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Newton potential is reformulated in terms of the Hausdorff distance to design reduced affine mappings associated fractal attractors. By applying maximum entropy analysis to observed patterns, stochastic features are extracted as well as boundary points where the fixed points of the mappings should be located. To linear segments of potential fixed points, feature points are nondeterministically attracted...
Vision Sensors for Cloud Applications have to drastically reduce the amount of image data that is transferred and stored. Due to the fact that such sensors are mostly bulk products, they must be optimized according to their performance, price, size and energy consumption. We present an approach for video compression that fulfills these needs by using FPGAs and allows scalability with respect to compression...
This paper provides a necessary condition good rate-distortion codes must satisfy. Specifically, it is shown that as the blocklength increases, the distribution of the input given the output of a good lossy code converges to the distribution of the input given the output of the joint distribution achieving the rate-distortion function, in terms of the normalized conditional relative entropy. The result...
We propose a new Write-Once-Memory (WOM) coding scheme based on source polarization. By applying a source polarization transformation on the to-be-determined codeword, the proposed WOM coding scheme encodes information into the bits in the high-entropy set. We prove in this paper that the proposed WOM codes are capacity-achieving. WOM codes have found many applications in modern data storage systems,...
Replicating or caching popular content in memories distributed across the network is a technique to reduce peak network loads. Conventionally, the performance gain of caching was thought to result from making part of the requested data available closer to end users. Recently, it has been shown that by using a carefully designed technique to store the contents in the cache and coding across data streams...
An efficient image encryption algorithm with improved image security has been developed by using chaotic function, deoxyribonucleic acid (DNA) sequencing and genetic algorithm (GA). A chaotic sequence of desired length is generated by using the logistic map function whose initial value is calculated using the secret key. A number of DNA masks are generated and these masks along with the chaotic sequences...
Although extensively investigated, the capacity of the two-hop half-duplex (HD) relay channel is not fully understood. In particular, a capacity expression which can be evaluated straightforwardly is not available and an explicit coding scheme which achieves the capacity is not known either. In this paper, we derive a new expression for the capacity of the two-hop HD relay channel based on a simplified...
We study the secrecy of a distributed storage system for passwords. The encoder, Alice, observes a length-n password and describes it using two hints, which she then stores in different locations. The legitimate receiver, Bob, observes both hints. In one scenario we require that the number of guesses it takes Bob to guess the password approach 1 as n tends to infinity and in the other that the size...
Hadamard transform (HT) over the binary field provides a natural way to implement multiple-rate codes (referred to as HT-coset codes), where the code length N = 2p is fixed but the code dimension K can be varied from 1 to N − 1 by adjusting the set of frozen bits. The HT-coset codes, including Reed-Muller (RM) codes and polar codes as typical examples, can share a pair of encoder and decoder with...
In this paper, we present a parallelized HEVC decoder by restructuring the reference HEVC decoder, HM, as a task graph with LCU level granularity. Since the task graph reveals the potential parallelism of the algorithm explicitly, we are able to explore the wide design space of parallelization efficiently. Moreover, we propose an analytical method to estimate the throughput performance of the HEVC...
As one of the emerging technologies with most potential for developing, Network Coding (NC) has gained significant momentum. Due to encode-and-forward model, NC has natural privacy in communication, but it also induces that attackers become more imperceptible and impact on NC caused by them becomes more far-reaching. This requires that the security schemes should consider the characteristics of different...
Self-Organization is based on adaptivity. Adaptivity should start with the very basic fundamental communication tasks such as encoding the information to be transmitted or stored. Obviously, the less signal transmitted the less energy in transmission used. In this paper we present a novel on-line and entropy adaptive compression scheme for streaming unbounded length inputs. The scheme extends the...
Nowadays, voice over IP (VoIP) is rapidly replacing standard phone line as a telephony service of choices. However, VoIP can be exploited by an attacker using method such as eavesdropping, hijacking and etc. To ensure confidentiality and integrity of the conversation or messages sent in the network, a more secure protocol is needed. This research proposes a solution to enhance the security of VoIP...
Wireless video stream delivery is choppy. This problem becomes much severer in MU-MIMO's simultaneous video transmission within the same band. Conventional schemes achieve graceful video delivery by harnessing from high data redundancy. However, with concurrent transmission in the same band, the leverage of high data redundancy leads to high probability of collisions and packets loss, which limits...
Cognitive processes, such as working memory, are widely considered as dynamic, and they are believed to involve complex functional information flows in large-scale brain networks. However, traditional voxel-based fMRI time series analysis methods, which essentially assume that the hemodynamic responses of involved brain regions follow the block or event-related paradigms, are limited in recognizing...
Compressed bit vectors supporting rank and select operations are the workhorse of compressed data structures. We propose a hybrid scheme for implementing compressed bit vectors, which divides the bit vector into blocks and then chooses the encoding of each block separately from a number of different encoding methods. Hybrid encoding is particularly suitable for bit vectors that have lots of local...
In this paper we develop a simple and practical text indexing scheme for compressed suffix arrays (CSA). For a text of n characters, our CSA can be constructed in linear time and needs 2nHk + n + o(n) bits of space for any k&le; clog&sigma;n -- 1 and any constant c < 1, where Hk denotes the kth order entropy. We compare the performance of our method with two established compressed...
In this paper we propose a reversible string transformation method that could be used to decrease entropy in input messages. The method is based on context information included in the structure we call a context map. The method is used to manipulate with symbols distribution. Since the change in distribution of symbols is followed by change in entropy, we could use cases when entropy is decreasing...
We investigate the usage of the wavelet tree and the rank/select-dictionary data structures on hybrid-structured variable-length codes, which represent an integer in the form of a unary code section followed by a binary section. We propose to handle unary and binary partitions as separate streams and create wavelet trees or R/S dictionaries over the unary streams, which grants us the opportunity to...
The issue of backwards compatible image and video coding gained some attention in both MPEG and JPEG, let it be as extension for HEVC, let it be as the JPEG XT standardization initiative of the SC29WG1 committee. The coding systems work all on the principle of a base layer, perating in the low-dynamic range regime, using a one-mapped version of the HDR material as input, and an extension layer invisible...
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