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We identify an analytical expression for the distortion of a scalable video bitstream. Relying on the distortion expression, we propose a low complexity distortion-optimal unequal error protection (UEP) method for the transmission of such video bitstream over wireless tandem channels. Utilizing a one-dimensional forward error correction (FEC) coding scheme, our proposed transmission method protects...
Consider an m-ary memoryless source, producing symbols alpha1,..., alpham with probabilities p1, ..., pm. We assume that instead of true probabilities, we have to use their approximate values pcirc1, ..., pcircm with maximum absolute error: delta* = maxi|pi - pcirci| . By Pmin = mini {pi} we denote the smallest source's probability. We assume that pmin > 0, and that it is relatively large w.r.t...
The primary objective of our research was to design an efficient way of compressing HTML documents, which will reduce Internet's traffic or will reduce storage requirements of HTML data. In our work we present the lossless HTML transform (LHT) aiming to improve lossless HTML compression in combination with existing general purpose compressors. The main components of our algorithm are: a static dictionary...
Motivated by sensor networks, we consider the fusion storage of correlated sources in a database, such that any subset of them may be efficiently retrieved in the future. Only statistical information about future queries is available during encoding and storage. Fusion coding of correlated sources poses new challenges due to the conflicting objectives of exploiting inter-source correlations and enabling...
Summary form only given. Significant work has been performed on encrypting images and compressing images as two separate problems, but traditional encryption techniques generally degrade the compression ratio. To circumvent these issues, two methods have been used. The first employs known encryption algorithms on compressed image data. The second develops compression algorithms which work well for...
In this paper, we attempt to overcome the limitation of specific scalable video codec and apply FEC-MDC to a common video coder, such as the standard H.264. The proposed scheme is explained as follows. Firstly, according to motion vector changes, an original video sequence is divided into several sub-sequences as messages, so in each message better temporal correlation can be maintained for better...
We present a nonlinear lossless compressor for multispectral images that exploits both intraband and interband correlations. A 2-dimensional wavelet transform is performed on each image band, and then the interband and remaining intraband correlations are exploited via an affine prediction of the wavelet coefficients, conditioning it to class information.
In a previous paper we derived an upper bound on the redundancy of an arithmetic-type encoder for a memoryless source, designed to meet a finite end- to-end strict delay constraint. It was shown that the redundancy decays exponentially with the delay constraint and that the redundancy-delay exponent is lower bounded by log(1/alpha) where alpha is the probability of the most likely source symbol. In...
In this paper we introduce an adaptive technique for compressing small quantities of text which are organized as a rooted directed graph. We impose a constraint on the technique such that data encountered during a traversal of any valid path through the graph must be recoverable without requiring the expansion of data that is not on the path in question. While compression can be applied independently...
In this paper, we attempt to solve the compressed image restoration by considering the recovery of spectral information in compressed images. For each NxN block in images, we convert the recovery problem to a route searching process in the N2-dimensional vector space RN2 spanned by all DCT coefficients. The quantized DCT coefficients vectors A capped is known as the starting node of the route, while...
We develop a new class of algorithms for losslessly compressing integer sequences that are monotone or quasi-monotone. We combine aspects of standard entropy codes as expressed in binary adaptive sequential coding (BASC) and monotone length (MOL) coding, with an aspect of binary interpolative (BI) coding.
The sequential context modeling framework is generalized to a non-sequential one by context relaxation from consecutive suffix of the subsequences of symbols to the permutation of the preceding symbols as result of considering complex context structures in such sources as video and program binaries. Context weighting tree is also extended to a series of context trees which are built according to the...
This work presents two new algorithms to predict the file size of a JPEG image subject to transformations consisting of simultaneous changes in resolution (scaling) and in quality factor (QF). To be computationally efficient, the prediction is based solely on easily accessible image parameters such as the quality factor and the original file size. A large image corpus (100,000 images), gathered by...
To overcome these drawbacks, a new bidirectional motion estimation algorithm for videoconferencing application at very low bit rate is proposed. The approach is based on spatio-temporal spline interpolation. The proposed algorithm processes as follows. Some frames in the original video sequence are purposely missed. Afterwards, these frames are predicted by the decoder side using only the transmitted...
It was recently shown that the symmetric multiple-description (MD) quadratic rate-distortion function for memoryless Gaussian sources and two descriptions can be achieved by dithered delta-sigma quantization combined with memoryless entropy coding. In this paper, we generalize this result to stationary (colored) Gaussian sources by combining noise shaping and source prediction. We first propose a...
We investigate the usage of edge-based inpainting as an intra prediction method in block-based image compression. The joint utilization of edge information and the well-known Laplace equation yields a simple and effective inpainting algorithm. As for intra prediction, the edge-based inpainting is a uniform solution, yet adaptive to local image features. During the integration of edge-based inpainting...
This paper considers the problem of distributed scalable coding of correlated sources that are communicated to a central unit. The general setting is typically encountered in sensor networks. The conditions of communication channels between the sensor sources and fusion center may be time-varying and it is often desirable to guarantee a base layer of coarse information during channel fades. Specifically,...
The Range Minimum Query (RMQ) Problem is to preprocess an array A of length n in 0(n) time such that subsequent on-line queries asking for the position of a minimal element between two specified indices can be obtained in constant time. Several solutions to this problem have been proposed, starting with Berkman and Vishkin's linear-space solution [6], and leading to a succinct solution using only...
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