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| | Lossless data compression - Wikipedia, the free encyclopedia |
 | | Lossless data compression is used in software compression tools such as the highly popular ZIP file format, used by PKZIP, WinZip, and Mac OS X, and the Unix programs bzip2, gzip and compress. | | | Most lossless compression programs use two different kinds of algorithms: one which generates a statistical model for the input data, and another which maps the input data to bit strings using this model in such a way that "probable" (e.g. | | | Whilst, in principle, any general-purpose lossless compression algorithm (general-purpose means that they can handle all binary input) can be used on any type of data, many are unable to achieve significant compression on data that is not of the form that they are designed to deal with. |
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http://en.wikipedia.org/wiki/Lossless_data_compression
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| | Data compression - Wikipedia, the free encyclopedia |
| | In computer science and information theory, data compression or source coding is the process of encoding information using fewer bits (or other information-bearing units) than an unencoded representation would use through use of specific encoding schemes. | | | One popular instance of compression that many computer users are familiar with is the ZIP file format, which, as well as providing compression, acts as an archiver, storing many files in a single output file. | | | One very simple means of compression, for example, is run-length encoding, wherein large runs of consecutive identical data values are replaced by a simple code with the data value and length of the run. |
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http://en.wikipedia.org/wiki/Data_compression
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| | [1.0] Introduction / Lossless Data Compression |
| | Data bytes are data bytes, regardless of whether they define text characters, or graphics data, or measurement data being returned from a space probe. | | | * A more sophisticated and efficient lossless compression technique is known as "Huffman coding", in which the characters in a data file are converted to a binary code, where the most common characters in the file have the shortest binary codes, and the least common have the longest. | | | Compression software can scan through the file, find these redundant strings of characters, and then store them using an escape character (ASCII 27), followed by the character and a binary count of the number of times it is repeated. |
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http://www.vectorsite.net/ttdcmp1.html
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| | Lossless Wavelet Compression |
| | The window of data that the compression algorithm is applied to in forecasting may be even smaller. | | | The object of a compression algorithm is to represent the original data in fewer bits. | | | The decompressed result of a lossy compression algorithm is an approximation of the orignal data. |
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http://www.bearcave.com/misl/misl_tech/wavelets/compression
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| | Theory of Data Compression |
| | That is, given the code table and given the compressed data, we should be able to rederive the original data. | | | Thus, the theorem established that the entropy rate is the rate of an optimal lossless data compression code. | | | In lossy data compression, the decompressed data need not be exactly the same as the original data. |
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http://www.data-compression.com/theory.html
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| | Lossless Data Compression |
| | Unix compress and uncompress, gzip and gunzip, and Windows WinZip) are based on the Lempel-Ziv algorithm. | | | This is because the length of the input data in the example is too short. | | | The main objective of this page is to introduce two important lossless compression algorithms: Huffman Coding and Lempel-Ziv Coding. |
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http://www.data-compression.com/lossless.html
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| | ITinfo: Lossless Data Compression |
| | Lossless data compression is the process by which digital information is compacted, stored and then restored to its original format without losing or changing the information. | | | Should ZeoSync's new compression algorithm be adopted by compression software developers, it could easily change the face of digital data compression. | | | ZeoSync's tests were conducted on a small scale; however, if the compression algorithm holds true for larger amounts of data, it could revolutionize the data storage and telecommunication industries. |
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http://www.dgl.com/itinfo/2002/it020109.html
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| | DataCompression.info - Lossless Compression |
| | DCG Framework is a object oriented framework for lossless data compression. | | | Not sure what algorithm they are using, it is described as "GEMAC's data compression algorithm." This algorithm was first published at DCC '95, and is described as a hybrid of ZL1 and ZL2, created with the goal of maximizing compression rate. |
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http://datacompression.info/Lossless.shtml
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| | Maximum Compression (lossless data compression software) |
| | The problem with different compression sizes in GUI and command-line is caused by a bug in the beta 2 version of the program. | | | This is *much* higher then current compression software is capable of. | | | If you are looking for data like (de)compression speed of compression software have a look at the Multiple file compression test benchmarks. |
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http://www.maximumcompression.com
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| | Lossless Data Compression |
| | Capable of simultaneous compression and decompression, with speeds ranging from 16 to 66 Mbytes/second, AHA's premier lossless data compression products are based on proprietary algorithms developed specifically to optimize bit-mapped data in memory intensive applications. | | | Used primarily in data storage, AHA offers a complete family of ALDC integrated circuits based on the LZ1 (Lempel-Ziv 1) class of data compression algorithms. | | | Of the many algorithms available to tape storage manufacturers, ALDC is the highest-rated data compression technology at 2.6:1. |
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http://www.aha.com/show_tech.php?id=1
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| | CS590N/ECE501L: Lossless Data Compression |
| | In writing the program, you can work in teams of two students, and each team is to turn in one report documenting the programs, usage instructions, explaining the code representation, et cetera. | | | With this in mind, you will notice that using a high-order model poses special difficulties that would require appropriate data structures to address memory and time complexity issues as well as the semi-static coding overhead. | | | Consequently, for any given file, the base source alphabet has up to 256 symbols, and an n-gram means that n-byte groups are taken as basic symbols of counting and coding. |
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http://www.cstp.umkc.edu/~oguzn/cs590n/ws04/project/projb.html
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| | Open Directory - Computers: Software: Data Compression |
| | Zzip compression algorithm is mainly based on the Burrows-Wheeler Transform method developped by Mike Burrows and David Wheeler. | | | Hifn Inc. - Designs, develops, and markets compression processors, encryption/compression processors, and software which provide alternatives for the implementation of high performance networks and tape storage devices. | | | WinZip - WinZip is a windows data compression utility that focuses on the Zip data compression format for windows users. |
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http://dmoz.org/Computers/Software/Data_Compression
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| | Lossless Data Compression, Fall 2005 |
| | Presentation of the ldc object oriented java framework for data compression. | | | This should give you a subdirectory named ldc, containing several files with java source code. | | | To install the java framework for the course on a linux machine, go to a designated directory and run |
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http://www.daimi.au.dk/~bromille/DC05/lossless.html
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| | Adaptive Lossless Data Compression (ALDC) |
| | ALDC is a lossless algorithm, insuring that the decompressed data output is exactly the same as the uncompressed data input. | | | The ALDC (Adaptive Lossless Data Compression) algorithm is one variant of the LZ1 (Lempel-Ziv 1) class of data compression algorithms, first proposed by Abraham Lempel and Jacob Ziv in 1977. | | | The encoder does this using the input data it receives for compression, while the decoder generates an identical data stream as its output, which it also uses for the update process. |
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http://www.aha.com/show_prod_type.php?id=4
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| | Universal Source Encoding for Science Data (USES) Lossless Data Compression Technique |
| | Universal Source Encoding for Science Data (USES), originally developed as Universal Source Encoding for Space (aka, USES), is a lossless data compression technique best suited for science data of various instruments. | | | Universal Source Encoding for Science Data (USES) Lossless Data Compression Technique | | | [1] Jack Venbrux, Pen-Shu Yeh and Muye N. Liu, "A VLSI Chip Set for High-Speed Lossless Data Compression," IEEE Trans. |
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http://gcmd.gsfc.nasa.gov/records/01-uses-01.html
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| | Energy Aware Lossless Data Compression - BARR, ASANOVIC (ResearchIndex) |
| | 14 A unified header compression framework for low-bandwidth lin.. | | | 3 RFC Compressing TCPIP header low speed serial link (context) - Compressing, headers et al. | | | If the energy required to compress data is less than the energy required to send it, there is a net energy savings and consequently, a longer battery life for portable computers. |
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http://citeseer.ist.psu.edu/584313.html
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| | Lossless data compression with low complexity (US6043763) |
| | Weinberger, et al., "LOCO-I: A Low Complexity, Context-Based, Lossless Image Compression Algorithm," IEEE Computer Society Press, Mar. 31-Apr. 3, 1996, pp. | | | Show 3 U.S. patent(s) that reference this one | | | An adaptive predictor is used to predict samples, and residuals from such predictions are encoded using Golomb-Rice encoding to thereby compress a digital signal which includes the samples. |
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http://www.delphion.com/details?pn=US06043763__
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| | Lossless Data Compression |
| | Suffice it to say that three common techniques used are runlength encoding (removing repetitions of values and replacing them with a counter and single value), Huffman coding, and dictionary techniques such as the Lempel-Ziv family of substitutional compression algorithms. | | | There is a huge range of data compression techniques - these are of some interest to the multimedia systems designer, but there are many good books on them already. |
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http://www.cs.odu.edu/~cs778/crowcroft/book/node98.html
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| | EDN: Lossless data-compression IC packs variable sectors: hardwired algorithm linked to 8-bit microprocessor ... |
| | Search for more information on HighBeam Research for. | | | EDN: Lossless data-compression IC packs variable sectors: hardwired algorithm linked to 8-bit microprocessor interface.(InfoChip Systems' IC-105 coprocessor.) (product announcement)@ HighBeam Research | | | The embedded algorithm is essentially a reduced Markov coding model, treating packets as sectors, removing redundancy to improve disk capacity and automatically passing through uncompressible data. |
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http://www.highbeam.com/library/doc0.asp?docid=1G1:8437472&refid=ink_tptd_mag
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| | The Art Of Lossless Data Compression |
| | Compression time is divided by 10 here, because more than 90% of people would never compress anything during their life (with compression programs), but they use compressed data almost _every_ time they use computers and/or Internet. | | | Here are the results of tests performed in August 2002 to compare lossless compression of "plain" texts by all known good enough programs developed for such purpose, including UHArc, PPMd, Bzip2, RAR, ACE and 7-zip. | | | That's why compression time is not so actual for them. |
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http://www.compression.ru/artest/texts25.html
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| | Data Compression |
| | For example, this was written before gzip and the "deflate" algorithm existed, at a time when "freeze" was being explored as a replacement for the UNIX "compress" command. | | | This is a twelve-part course on lossless data compression. | | | For anyone intrigued by the "stackable" compression modules described in lesson 12, I have made the complete source code to HardPressed available on this site. |
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http://www.fadden.com/techmisc/hdc
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| | PCMag.com Shareware Library: The Art Of Lossless Data Compression 22 |
| | PCMag.com Shareware Library: The Art Of Lossless Data Compression 22 | | | Home > Downloads > Shareware Library > Utilities/Drivers/System Files › Archiving and compressing programs › The Art Of Lossless Data Compression 22 | | | PC Magazine is a registered trademark of Ziff Davis Publishing Holdings Inc. Reproduction in whole or in part in any form or medium without express written permission of Ziff Davis Media Inc. is prohibited. |
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http://shareware.pcmag.com/product.php[id]54365[cid]13[SiteID]pcmag
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| | LZAC Lossless Data Compression |
| | Usage of this product signifies your acceptance of the Terms of Use. | | | Citation: A. Chu, "LZAC Lossless Data Compression," dcc, p. |
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http://csdl.computer.org/comp/proceedings/dcc/2002/1477/00/14770449abs.htm
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