Proceedings DCC '97. Data Compression Conference最新文献_第4页

High performance arithmetic coding for small alphabets 小字母的高性能算术编码

Proceedings DCC '97. Data Compression Conference Pub Date : 1997-03-25 DOI: 10.1109/DCC.1997.582149

Xiaohui Xue, Wen Gao

引用次数: 3

Content-adaptive postfiltering for very low bit rate video 非常低比特率视频的内容自适应后滤波

Proceedings DCC '97. Data Compression Conference Pub Date : 1997-03-25 DOI: 10.1109/DCC.1997.581986

A. Jacquin, H. Okada, P. E. Crouch

引用次数: 14

Text compression via alphabet re-representation 通过字母重新表示的文本压缩

Proceedings DCC '97. Data Compression Conference Pub Date : 1997-03-25 DOI: 10.1109/DCC.1997.582003

Philip M. Long, A. Natsev, J. Vitter

引用次数: 10

Efficient context-based entropy coding for lossy wavelet image compression 基于上下文的有效熵编码用于有损小波图像压缩

Proceedings DCC '97. Data Compression Conference Pub Date : 1997-03-25 DOI: 10.1109/DCC.1997.582047

C. Chrysafis, Antonio Ortega

{"title":"Efficient context-based entropy coding for lossy wavelet image compression","authors":"C. Chrysafis, Antonio Ortega","doi":"10.1109/DCC.1997.582047","DOIUrl":"https://doi.org/10.1109/DCC.1997.582047","url":null,"abstract":"We present an adaptive image coding algorithm based on novel backward-adaptive quantization/classification techniques. We use a simple uniform scalar quantizer to quantize the image subbands. Our algorithm puts the coefficient into one of several classes depending on the values of neighboring previously quantized coefficients. These previously quantized coefficients form contexts which are used to characterize the subband data. To each context type corresponds a different probability model and thus each subband coefficient is compressed with an arithmetic coder having the appropriate model depending on that coefficient's neighborhood. We show how the context selection can be driven by rate-distortion criteria, by choosing the contexts in a way that the total distortion for a given bit rate is minimized. Moreover the probability models for each context are initialized/updated in a very efficient way so that practically no overhead information has to be sent to the decoder. Our results are comparable or in some cases better than the recent state of the art, with our algorithm being simpler than most of the published algorithms of comparable performance.","PeriodicalId":403990,"journal":{"name":"Proceedings DCC '97. Data Compression Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128527063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 135

Robust image coding with perceptual-based scalability 基于感知可扩展性的鲁棒图像编码

Proceedings DCC '97. Data Compression Conference Pub Date : 1997-03-25 DOI: 10.1109/DCC.1997.582133

M. G. Ramos, S. Hemami

{"title":"Robust image coding with perceptual-based scalability","authors":"M. G. Ramos, S. Hemami","doi":"10.1109/DCC.1997.582133","DOIUrl":"https://doi.org/10.1109/DCC.1997.582133","url":null,"abstract":"Summary form only given. We present a multiresolution-based image coding technique that achieves high visual quality through perceptual-based scalability and robustness to transmission errors. To achieve perceptual coding, the image is first segmented at a block level (16/spl times/16) into smooth, edge, and highly-detailed regions, using the Holder regularity property of the wavelet coefficients as well as their distributions. The activity classifications are used when coding the high-frequency wavelet coefficients. The image is compressed by first performing a 3-level hierarchical decomposition, yielding 10 subbands which are coded independently. The LL band is coded using reconstruction-optimized lapped orthogonal transforms, followed by quantization, runlength encoding, and Huffman coding. The high-frequency coefficients corresponding to the smooth regions are quantized to zero. The high-frequency coefficients corresponding to the edge regions are uniformly quantized, to maintain Holder regularity and sharpness of the edges, while those corresponding to the highly-detailed regions are quantized with a modified uniform quantizer with a dead zone. Bits are allocated based on the scale and orientation selectivity of each high-frequency subband as well as the activity regions inside each band corresponding to the edge and highly-detailed regions of the image. The quantized high-frequency bands are then run-length encoded.","PeriodicalId":403990,"journal":{"name":"Proceedings DCC '97. Data Compression Conference","volume":"55 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114104468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 9

Low-cost prevention of error-propagation for data compression with dynamic dictionaries 使用动态字典对数据压缩进行错误传播的低成本预防

Proceedings DCC '97. Data Compression Conference Pub Date : 1997-03-25 DOI: 10.1109/DCC.1997.582007

J. Storer, J. Reif

引用次数: 7

Significantly lower entropy estimates for natural DNA sequences 显著降低了自然DNA序列的熵估计

Proceedings DCC '97. Data Compression Conference Pub Date : 1997-03-25 DOI: 10.1109/DCC.1997.581998

D. Loewenstern, P. Yianilos

{"title":"Significantly lower entropy estimates for natural DNA sequences","authors":"D. Loewenstern, P. Yianilos","doi":"10.1109/DCC.1997.581998","DOIUrl":"https://doi.org/10.1109/DCC.1997.581998","url":null,"abstract":"If DNA were a random string over its alphabet {A,C,G,T}, an optimal code would assign 2 bits to each nucleotide. We imagine DNA to be a highly ordered, purposeful molecule, and might therefore reasonably expect statistical models of its string representation to produce much lower entropy estimates. Surprisingly this has not been the case for many natural DNA sequences, including portions of the human genome. We introduce a new statistical model (compression algorithm), the strongest reported to date, for naturally occurring DNA sequences. Conventional techniques code a nucleotide using only slightly fewer bits (1.90) than one obtains by relying only on the frequency statistics of individual nucleotides (1.95). Our method in some cases increases this gap by more than five-fold (1.66) and may lead to better performance in microbiological pattern recognition applications. One of our main contributions, and the principle source of these improvements, is the formal inclusion of inexact match information in the model. The existence of matches at various distances forms a panel of experts which are then combined into a single prediction. The structure of this combination is novel and its parameters are learned using expectation maximization (EM).","PeriodicalId":403990,"journal":{"name":"Proceedings DCC '97. Data Compression Conference","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127523276","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 136

Efficient approximate adaptive coding 高效近似自适应编码

Proceedings DCC '97. Data Compression Conference Pub Date : 1997-03-25 DOI: 10.1109/DCC.1997.582059

A. Turpin, Alistair Moffat

{"title":"Efficient approximate adaptive coding","authors":"A. Turpin, Alistair Moffat","doi":"10.1109/DCC.1997.582059","DOIUrl":"https://doi.org/10.1109/DCC.1997.582059","url":null,"abstract":"We describe a mechanism for approximate adaptive coding that makes use of deferred probability update to obtain good throughput rates with no buffering of symbols from the input message. Our proposed mechanism makes use of a novel code calculation process that allows an approximate code for a message of m symbols to be calculated in O(log m) time, improving upon previous methods. We also give analysis that bounds both the total computation time required to encode a message using the approximate code and the inefficiency of the resulting codeword set. Finally, experimental results are given that highlight the role the new method might play in a practical compression system. The current work builds upon two earlier papers. We previously described a mechanism for efficiently calculating a minimum-redundancy code for an alphabet in which there are many symbols with the same frequency of occurrence. We impose a modest amount of additional discipline upon the input frequencies, and show how the calculation of codewords can be performed in time and space logarithmic in the length of the message. The second area we have previously examined is the process of manipulating a code to actually perform compression. We examined mechanisms for encoding and decoding a prefix code that avoid any need for explicit enumeration of the source codewords. This means that we are free to change the source codewords at will during a message without incurring the additional cost of completely recalculating an n entry codebook.","PeriodicalId":403990,"journal":{"name":"Proceedings DCC '97. Data Compression Conference","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127473037","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Recursive block structured data compression 递归块结构数据压缩

Proceedings DCC '97. Data Compression Conference Pub Date : 1997-03-25 DOI: 10.1109/DCC.1997.582139

M. Tilgner, M. Ishida, T. Yamaguchi

引用次数: 4

Image coding using optimized significance tree quantization 图像编码采用优化的显著性树量化

Proceedings DCC '97. Data Compression Conference Pub Date : 1997-03-25 DOI: 10.1109/DCC.1997.582064

G. Davis, S. Chawla

引用次数: 45