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Efremenko showed locally-decodable codes of subexponential length that can handle close to 1/6 fraction of errors. In this paper we show that the same codes can be locally unique-decoded from error rate 1/2 - α for any α > 0 and locally list-decoded from error rate 1 - α for any α > 0, with only a constant number of queries and a constant alphabet size. This gives the first sub-exponential length...
In this paper, we consider coding schemes for computationally bounded channels, which can introduce an arbitrary set of errors as long as (a) the fraction of errors is bounded with high probability by a parameter p and (b) the process which adds the errors can be described by a sufficiently "simple" circuit. Codes for such channel models are attractive since, like codes for standard adversarial...
In MIMO communication system the conventional Turbo-BLAST receiver using Gray mapping converges slow. For this reason, an improved Turbo-BLAST scheme with Anti-Gray mapping is proposed in this paper. Research has shown that the iterative receiver using new scheme outperforms the convention alone and obtains a faster convergence rate. Also, an improved receiver based on soft interference cancellation...
It is need to carry on the compression to the remote sensing image for the speedy transmission and the effective memory remote sensing image. The multi-spectrum remote sensing image has the very strong relevance among spectrums. In multi-wave band image compression, to eliminate the spectrum relevance, both must consider to eliminate the statistical dependence, and to eliminate the structure relevance...
Distributed video coding (DVC) is a novel approach providing new features as low complexity encoding by mainly exploiting the source statistics at the decoder based on the availability of decoder side information. In this paper, scalable-to-lossless DVC is presented based on extending a lossy Transform Domain Wyner-Ziv (TDWZ) distributed video codec with feedback. The lossless coding is obtained by...
Distributed video coding is a new paradigm for video compression based on the Slepian-Wolf and Wyner-Ziv theorems. Wyner-Ziv video coding, a lossy compression with receiver side information, enables low-complexity video encoding at the expense of a complex decoder. Most of the existing distributed video coding techniques require a feedback channel to determine the number of parity bits for decoding...
Most distributed source coding schemes involve the application of a channel code to the signal and transmission of the resulting syndromes. For low-complexity encoding with superior compression performance, graph-based channel codes such as LDPC codes are used to generate the syndromes. The encoder performs simple XOR operations, while the decoder uses belief propagation (BP) decoding to recover the...
Side information generation is a critical step in distributed video coding systems. This is performed by using motion compensated temporal interpolation between two or more key frames (KFs). However, when the temporal distance between key frames increases (i.e. when the GOP size becomes large), the linear interpolation becomes less effective. In a previous work we showed that this problem can be mitigated...
In this paper, we present a novel, frequency-domain stereo to mono downmixing, which preserves the energy of spectral components and avoids setting the left or right channel as a phase reference. Based on this downmixing technique, a parametric stereo analysis-synthesis model is described in which subband stereo parameters consist of interchannel level differences and phase differences between the...
A digital phase-locked loop (DPLL) is designed using 0.18 mm CMOS process and a 3.3 V power supply. It operates in the frequency range 200 MHz-1 GHz. The DPLL operation includes two stages: (i) a novel coarse-tuning stage based on a flash algorithm, and (ii) a fine-tuning stage similar to conventional DPLLs. The flash portion of the DPLL is made up of frequency comparators, an encoder and a decoder...
Novel coding tools have been proposed recently to encode texture and depth maps of multiview images, exploiting inter-view correlations, for depth-image-based rendering (DIBR). However, the important associated bit allocation problem for DIBR remains open: for chosen view coding and synthesis tools, how to allocate bits among texture and depth maps across encoded views, so that the fidelity of a set...
This paper focuses on recent research on unequal error protection random linear coding (UEP RLC) for applications in network coded (NC) multimedia communications. We define a class of UEP RLC called expanding window random linear coding (EW-RLC) and provide exact decoding probability analysis for different importance classes of the source data assuming the Gaussian Elimination (GE) decoder applied...
In light of the recent development of multimedia and networking technologies, an exponentially increasing amount of content is available via various public services. That is why content identification attracts a lot of attention. One possible technology for content identification is based on digital fingerprinting. When trying to establish information-theoretic limits in this application, usually...
This article is a theoretical study on binary Tardos' fingerprinting codes embedded using watermarking schemes. Our approach is derived from and encompasses both security and robustness constraints. We assume here that the coalition has estimated the symbols of the fingerprinting code by the way of a security attack, the quality of the estimation relying on the security of the watermarking scheme...
Transmission of compressed video over unreliable networks is vulnerable to errors and error propagation. Multi-hypothesis motion compensated prediction (MHMCP) which was originally developed to improve compression efficiency has been shown to have a good error resilience property. In this paper we improve the overall performance of MHMCP in packet loss scenarios by performing optimal mode switching...
With the rapid development of multimedia technology, video transmission over error prone channels is widely used. Using predictive video coding can lead to temporal and spatial propagation of channel errors, which consequently results in high degradation in the quality of the received video. In order to address this problem different error resilient methods have been proposed. In this paper, a number...
We consider the problem of recovering a signal/image (x) with a k-sparse representation, from hybrid (complex and real), noiseless linear samples (y) using a mixture of complex-valued sparse and real-valued dense projections within a single matrix. The proposed Hybrid Compressed Sensing (HCS) employs the complex-sparse part of the projection matrix to divide the n-dimensional signal (x) into subsets...
In this paper, we present a solution to efficient multimedia streaming applications over P2P networks based on the foresighted resource reciprocation strategy. We study several priority functions that can explicitly consider the timing constraints and the importance of each data segment in terms of multimedia quality, and successfully incorporate them into the foresighted resource reciprocation strategy...
Joint source-channel decoding (JSCD) exploits residual redundancy in compressed bitstreams to improve the robustness to transmission errors of multimedia coding schemes. This paper proposes an architecture to introduce some additional side information in compressed streams to help JSCD. This architecture exploits a reference decoder already present or introduced at the encoder side. An application...
This paper focuses on the rate-distortion optimization of low-delay 3D video communications based on the latest H.264/MVC video coding standard. The first part of the work proposes a new low-complexity model for distortion estimation suitable for low-delay stereoscopic video communication scenarios such as 3D videoconferencing. The distortion introduced by the loss of a given frame is investigated...
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