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In this work, we present a SSIM optimal JPEG 2000 rate allocation algorithm. However, our aim is less improving the visual performance of JPEG 2000, but more the study of the performance of the SSIM full reference metric by means beyond correlation measurements.Full reference image quality metrics assign a quality index to a pair of a reference and distorted image. The performance of a metric is then...
For mobile image matching applications, a mobile device captures a query image, extracts descriptive features, and transmits these features wirelessly to a server. The server recognizes the query image by comparing the extracted features to its database and returns information associated with the recognition result. For slow links, query feature compression is crucial for low-latency retrieval. Previous...
We consider lossy compression of image sequences using lscr1 compression with over complete dictionaries. As a fidelity measure for the reconstruction quality, we incorporate the proposed structural similarity index measure, and we show that this leads to problem formulations that are very similar to conventional lscr1 compression algorithms. In addition, we develop efficient large-scale algorithms...
We introduce a novel universal refinable trellis quantization scheme (URTCQ) that is suitable for bitplane coding with many reconstruction stages. Existing refinable trellis quantizers either require excessive codebook training and are outperformed by scalar quantization for more than two stages (MS-TCQ, E-TCQ), require a huge computational burden (SR-TCQ) or achieve a good rate distortion performance...
In this paper, we introduce an analytical expression for the expected distortion of a single layer encoded video bit-stream. Based on the expected distortion model, we propose a distortion optimal unequal error protection (UEP) technique to transmit such bit-stream over a wireless tandem channel. The proposed method allocates the total transmission budget unequally to different frames of a video bit-stream...
We investigate the performance of a discrete-time all-analog-processing joint source channel coding system for the transmission of i.i.d. Gaussian and Laplacian sources over AWGN channels. In the encoder, two samples of an i.i.d. source are mapped into a channel symbol using a space-filling curve. Different from previous work in the literature, MMSE decoding instead of ML decoding is considered, and...
Kernel machines are a popular class of machine learning algorithms that achieve state of the art accuracies on many real-life classification problems. Kernel perceptrons are among the most popular online kernel machines that are known to achieve high-quality classification despite their simplicity. They are represented by a set of B prototype examples, called support vectors, and their associated...
An efficient rate allocation algorithm for the progressive transmission of multiple images over time-varying noisy channels is proposed. The algorithm is initiated by the distortion optimal solution for the first image and searches for the optimal rate-allocation for each subsequent image in the neighborhood of the solution for the previous image. Given the initial solution, the algorithm is linear-time...
Data deduplication is a popular dictionary based compression method in storage archival and backup. The deduplication efficiency improves for smaller chunk sizes, however the files become highly fragmented requiring many disk accesses during reconstruction or chattiness in a client-server architecture. Within the sequence of chunks that an object (file) is decomposed into, sub-sequences of adjacent...
High resolution multi-spectral imagers are becoming increasingly important tools for studying and monitoring the earth. As much of the data from these multi-spectral imagers is used for quantitative analysis, the role of lossless compression is critical in the transmission, distribution, archiving, and management of the data. To evaluate the performance of various compression algorithms, we used data...
PRAM CREW parallel algorithms requiring logarithmic time and a linear number of processors exist for sliding (LZ1) and static dictionary compression. On the other hand, LZ2 compression seems hard to parallelize. Both adaptive methods work with prefix dictionaries, that is, all prefixes of a dictionary element are dictionary elements.Therefore, it is reasonable to use prefix dictionaries also for the...
In this paper, we studied the block LZSS algorithm and investigated the relationship between the compression ratio of block LZSS and the value of index or length. We found that as the block size increases, the compression ratio becomes better. We also found that the bit of length has little effect on the compression performance, and the bit of index has a significant effect on the compression ratio...
The following topics are dealt with: adaptive prefix coding; Huffman codes; joint source-channel coding; wireless sensor network; data compression; image sequences; and image coding.
Simulation results show that although the eIRA codes are exclusively optimized for the smallest and the largest puncture ratios, the gaps of compression rates with respect to the SW limits are small and similar over the given puncture ratio range.
An analysis is presented that extends existing Rayleigh-Ritz theory to the special case of highly eccentric distributions. Specifically, a bound on the angle between the first Ritz vector and the orthonormal projection of the first eigenvector is developed for the case of a random projection onto a lower-dimensional subspace. It is shown that this bound is expected to be small if the eigenvalues are...
This paper considers the problem of transmitting the difference of two positively correlated Gaussian sources over a two-user additive Gaussian noise multiple access channel (MAC). The goal is to recover this difference within an average mean squared error distortion criterion. Each transmitter has access to only one of the two Gaussian sources and is limited by an average power constraint. In this...
This paper is concerned with optimal transform coding in conjunction with dithered quantization. While the optimal deterministic quantizer's error is uncorrelated with the reconstructed value, the dithered quantizer yields quantization errors that are correlated with the reconstruction but are white and independent of the source. These properties offer potential benefits, but also have implications...
Summary form only given. Shift-variance and computational complexity are bottleneck of existing wavelet-based motion estimation (ME). Moreover, to the best of our knowledge, few works have been reported on wavelet-domain ME of video objects (VOs). In this paper, we present an efficient wavelet-domain approach to ME of arbitrarily shaped VOs.
The amount of information that is stored in digital form in more than one language is growing very fast as a consequence of the globalization. Furthermore, there are countries and supra-national entities whose legislation enforces the translation (and storage) of all the official texts into all their official languages. Two texts that are mutual translations are usually referred to as a bilingual...
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