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108
Compressed Bloom Filters
, 2001
"... A Bloom filter is a simple spaceefficient randomized data structure for representing a set in order to support membership queries. Although Bloom filters allow false positives, for many applications the space savings outweigh this drawback when the probability of an error is sufficiently low. We in ..."
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Cited by 193 (10 self)
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A Bloom filter is a simple spaceefficient randomized data structure for representing a set in order to support membership queries. Although Bloom filters allow false positives, for many applications the space savings outweigh this drawback when the probability of an error is sufficiently low. We introduce compressed Bloom filters, which improve performance when the Bloom filter is passed as a message, and its transmission size is a limiting factor. For example, Bloom filters have been suggested as a means for sharing Web cache information. In this setting, proxies do not share the exact contents of their caches, but instead periodically broadcast Bloom filters representing their cache. By using compressed Bloom filters, proxies can reduce the number of bits broadcast, the false positive rate, and/or the amount of computation per lookup. The cost is the processing time for compression and decompression, which can use simple arithmetic coding, and more memory use at the proxies, which utilize the larger uncompressed form of the Bloom filter.
Unbounded Length Contexts for PPM
 The Computer Journal
, 1995
"... uses considerably greater computational resources (both time and space). The next section describes the basic PPM compression scheme. Following that we motivate the use of contexts of unbounded length, introduce the new method, and show how it can be implemented using a trie data structure. Then we ..."
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Cited by 111 (7 self)
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uses considerably greater computational resources (both time and space). The next section describes the basic PPM compression scheme. Following that we motivate the use of contexts of unbounded length, introduce the new method, and show how it can be implemented using a trie data structure. Then we give some results that demonstrate an improvement of about 6% over the old method. Finally, a recentlypublished and seemingly unrelated compression scheme [2] is related to the unboundedcontext idea that forms the essential innovation of PPM*. 1 PPM: Prediction by partial match The basic idea of PPM is to use the last few characters in the input stream to predict the upcoming one. Models that condition their predictions on a few immediately preceding symbols are called "finitecontext" models of order k, where k is the number of preceding symbols used. PPM employs a suite of fixedorder context models with different values of k
Contextbased adaptive binary arithmetic coding in the h.264/avc video compression standard. Circuits and Systems for VideoTechnology, IEEETransactions on
"... (CABAC) as a normative part of the new ITUT/ISO/IEC standard H.264/AVC for video compression is presented. By combining an adaptive binary arithmetic coding technique with context modeling, a high degree of adaptation and redundancy reduction is achieved. The CABAC framework also includes a novel l ..."
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Cited by 110 (6 self)
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(CABAC) as a normative part of the new ITUT/ISO/IEC standard H.264/AVC for video compression is presented. By combining an adaptive binary arithmetic coding technique with context modeling, a high degree of adaptation and redundancy reduction is achieved. The CABAC framework also includes a novel lowcomplexity method for binary arithmetic coding and probability estimation that is well suited for efficient hardware and software implementations. CABAC significantly outperforms the baseline entropy coding method of H.264/AVC for the typical area of envisaged target applications. For a set of test sequences representing typical material used in broadcast applications and for a range of acceptable video quality of about 30 to 38 dB, average bitrate savings of 9%â€“14 % are achieved. Index Termsâ€”Binary arithmetic coding, CABAC, context modeling, entropy coding, H.264, MPEG4 AVC. I.
Compression and Explanation using Hierarchical Grammars
 Computer Journal
, 1997
"... This paper describes an algorithm, called SEQUITUR, that identifies hierarchical structure in ..."
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Cited by 85 (1 self)
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This paper describes an algorithm, called SEQUITUR, that identifies hierarchical structure in
Compressing Integers for Fast File Access
 The Computer Journal
, 1999
"... this paper we show experimentally that, for large or small collections, storing integers in a compressed format reduces the time required for either sequential stream access or random access. We compare di#erent approaches to compressing integers, including the Elias gamma and delta codes, Golom ..."
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Cited by 59 (14 self)
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this paper we show experimentally that, for large or small collections, storing integers in a compressed format reduces the time required for either sequential stream access or random access. We compare di#erent approaches to compressing integers, including the Elias gamma and delta codes, Golomb coding, and a variablebyte integer scheme. As a conclusion, we recommend that, for fast access to integers, files be stored compressed
Models of English text
, 1997
"... The problem of constructing models of English text is considered. A number of applications of such models including cryptology, spelling correction and speech recognition are reviewed. The best current models of English text have been the result of research into compression. Not only is this an impo ..."
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Cited by 49 (8 self)
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The problem of constructing models of English text is considered. A number of applications of such models including cryptology, spelling correction and speech recognition are reviewed. The best current models of English text have been the result of research into compression. Not only is this an important application of such models but the amount of compression provides a measure of how well such models perform. Three main classes of models are considered: character based models, word based models, and models which use auxilary information in the form of parts of speech. These models are compared in terms of their memory usage and compression.
Extended Application of Suffix Trees to Data Compression
 In Data Compression Conference
, 1996
"... A practical scheme for maintaining an index for a sliding window in optimal time and space, by use of a suffix tree, is presented. The index supports location of the longest matching substring in time proportional to the length of the match. The total time for build and update operations is proporti ..."
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Cited by 37 (2 self)
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A practical scheme for maintaining an index for a sliding window in optimal time and space, by use of a suffix tree, is presented. The index supports location of the longest matching substring in time proportional to the length of the match. The total time for build and update operations is proportional to the size of the input. The algorithm, which is simple and straightforward, is presented in detail. The most prominent lossless data compression scheme, when considering compression performance, is prediction by partial matching with unbounded context lengths (PPM*). However, previously presented algorithms are hardly practical, considering their extensive use of computational resources. We show that our scheme can be applied to PPM*style compression, obtaining an algorithm that runs in linear time, and in space bounded by an arbitrarily chosen window size. Application to ZivLempel '77 compression methods is straightforward and the resulting algorithm runs in linear time. 1 Introdu...
Text Image Compression Using Soft Pattern Matching
 Computer Journal
, 1997
"... this paper we describe a process which can be used for both lossless and lossy compression. For text documents at 200 dpi, our lossless compression ratios are between 20% and 65% better than those of the JBIG1 standard [1]. Our lossy compression ratios are between 2.0 and 4.6 times the lossless rat ..."
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Cited by 35 (9 self)
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this paper we describe a process which can be used for both lossless and lossy compression. For text documents at 200 dpi, our lossless compression ratios are between 20% and 65% better than those of the JBIG1 standard [1]. Our lossy compression ratios are between 2.0 and 4.6 times the lossless ratios of JBIG1, with only barely perceptible changes from the original. The lossless algorithm is similar to the method described by Mohiuddin et al. [2]; we extend the method to allow lossy compression by preprocessing each character in a way that reduces the number of bits output without noticeably distorting the character.
Bicubic SubdivisionSurface Wavelets for LargeScale Isosurface Representation and Visualization
, 2000
"... We introduce a new subdivisionsurface wavelet transform for arbitrary twomanifolds with boundary that is the first to use simple liftingstyle filtering operations with bicubic precision. We also describe a conversion process for remapping largescale isosurfaces to have subdivision connectivity ..."
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Cited by 34 (12 self)
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We introduce a new subdivisionsurface wavelet transform for arbitrary twomanifolds with boundary that is the first to use simple liftingstyle filtering operations with bicubic precision. We also describe a conversion process for remapping largescale isosurfaces to have subdivision connectivity and fair parameterizations so that the new wavelet transform can be used for compression and visualization. The main idea enabling our wavelet transform is the circular symmetrization of the filters in irregular neighborhoods, which replaces the traditional separation of filters into two 1D passes. Our wavelet transform uses polygonal base meshes to represent surface topology, from which a CatmullClarkstyle subdivision hierarchy is generated. The details between these levels of resolution are quickly computed and compactly stored as wavelet coefficients. The isosurface conversion process begins with a contour triangulation computed using conventional techniques, which we subsequently simplify with a variant edgecollapse procedure, followed by an edgeremoval process. This provides a coarse initial base mesh, which is subsequently refined, relaxed and attracted in phases to converge to the contour. The conversion is designed to produce smooth, untangled and minimally skewed parameterizations, which improves the subsequent compression after applying the transform. We have demonstrated our conversion and transform for an isosurface obtained from a highresolution turbulentmixing hydrodynamics simulation, showing the potential for compression and levelofdetail visualization.
High Performance Compression of Visual Information  A Tutorial Review  Part I: Still Pictures
, 1999
"... Digital images have become an important source of information in the modern world of communication systems. In their raw form, digital images require a tremendous amount of memory. Many research efforts have been devoted to the problem of image compression in the last two decades. Two different comp ..."
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Cited by 20 (0 self)
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Digital images have become an important source of information in the modern world of communication systems. In their raw form, digital images require a tremendous amount of memory. Many research efforts have been devoted to the problem of image compression in the last two decades. Two different compression categories must be distinguished: lossless and lossy. Lossless compression is achieved if no distortion is introduced in the coded image. Applications requiring this type of compression include medical imaging and satellite photography. For applications such as videotelephony or multimedia applications some loss of information is usually tolerated in exchange for a high compression ratio.