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| | Audio data compression - Wikipedia, the free encyclopedia |
 | | Perhaps the earliest algorithms used in speech encoding (and audio data compression in general) were the A-law algorithm and the mu-law algorithm. | | | In both lossy and lossless compression, information redundancy is reduced, using methods such as coding, pattern recognition and linear prediction to reduce the amount of information used to describe the data. | | | In contrast to the speed of compression, which is proportional to the number of operations required by the algorithm, here latency refers to the number of samples which must be analysed before a block of audio is processed. |
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http://en.wikipedia.org/wiki/Audio_data_compression
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| | Lossy data compression - Wikipedia, the free encyclopedia |
| | A lossy data compression method is one where compressing data and then decompressing it retrieves data that may well be different from the original, but is "close enough" to be useful in some way. | | | When a user acquires a lossily-compressed file, (for example, to reduce download-time) the retrieved file can be quite different from the original at the bit level while being indistinguishable to the human ear or eye for most practical purposes. | | | Good lossy compression algorithms are able to throw away "less important" information and still retain the "essential" information. |
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http://www.wikipedia.org/wiki/Lossy_data_compression
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| | Lossy data compression - Wikipedia, the free encyclopedia |
| | A lossy data compression method is one where compressing data and then decompressing it retrieves data that may well be different from the original, but is "close enough" to be useful in some way. | | | When a user acquires a lossily-compressed file, (for example, to reduce download-time) the retrieved file can be quite different from the original at the bit level while being indistinguishable to the human ear or eye for most practical purposes. | | | Good lossy compression algorithms are able to throw away "less important" information and still retain the "essential" information. |
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http://en.wikipedia.org/wiki/lossy_data_compression
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| | Lossy data compression - Hutchinson encyclopedia article about Lossy data compression |
| | In computing, data compression technique that dramatically reduces the size of a file by eliminating superfluous data. | | | The lost information is either unnoticeable to the user, or can be recovered during decompression by extrapolation of the existing data. | | | All content on this website, including dictionary, thesaurus, literature, geography, and other reference data is for informational purposes only. |
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http://encyclopedia.farlex.com/Lossy+data+compression
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| | Chebyshev Data Compression |
| | The algorithm has the property of requiring few computations to compress data, and it is therefore well suited to applications requiring real-time data compression in extreme terrestrial or extra-terrestrial environments. | | | To date, lossy data compression algorithms have found acceptance in applications where the need to achieve high compression ratios outweighs the information loss, but have not found acceptance in technical applications where preservation of absolute data values are important. | | | To be useful for time series data, a lossy compression algorithm needs to be optimized to preserve absolute data values to the extent possible within the available bandwidth. |
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http://www.jhuapl.edu/ott/technologies/technology/articles/P01825.asp
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| | FasterMac.net- |
| | To use an arithmetic coding algorithm to encode a data sequence, a statistical model is either built dynamically during the encoding process, or assumed to exist in advance. | | | During the encoding process, the original data sequence is parsed into non-overlapping, variable-length phrases according to a string matching mechanism, and then encoded phrase by phrase. | | | Conventional lossless data compression methods typically employ Huffman coding, run-length coding, arithmetic coding algorithms, Lempel-Ziv algorithms, and their variants. |
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http://www.fastermac.net/framework.cfm?page=turbomac-detail.html
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| | Data Compression for Beginners |
| | The basic idea behind Huffman coding is that the algorithm reads through the data and assigns sequences of binary code to the symbols used in the source. | | | Quantization is a complicated form of lossy data compression which can require lots of computer processing. | | | Data compression algorithms remove repeated and/or irreleva nt information from the data (Jacobson). |
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http://www.ils.unc.edu/~willc/dcfulltext.html
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| | Jonathan Mongiovi |
| | data is difference mapping, in which the image is represented as an array | | | The purpose of data compression is to represent an information source as | | | transfer data at a higher level of storage while reducing the amount of |
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http://uhaweb.hartford.edu/MONGIOVI/paper.html
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| | Research in Data Compression |
| | It is competitive with other competing technologies in terms of compression ratios, far superior in terms of decompression time (extremely fast even with weak computational resources), and promises to provide a way of treating uniformly all kinds of multimedia data (whereas current schemes use different technologies for each). | | | When investigating this aspect of compression (i.e., extension of Lempel-Ziv type compression to graphical objects), we expect that some of our work in the area of computational geometry to be helpful. | | | While it is know that the lossless Lempel-Ziv is asymptotically optimal (i.e., its compression ratio is close to the entropy), we have managed to prove recently that a lossy extension of Lempel-Ziv scheme (of low complexity) is suboptimal (cf. |
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http://www.cs.purdue.edu/homes/spa/software.html
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| | Lossy data compression |
| | A lossy data compression method is one where compressing data and then decompressing it retrieves data that may well be different from the original, but is "close enough" to be useful in some way. | | | Lossy Data Compression, with compression ratios far beyond those available with conventional zip, gzip or even bzip technologies, should have taken the world by storm. | | | By the late 1980s, extensive research pushed the development of lossy compression algorithms that take advantage of known limitations of the human eye. |
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http://www.logicjungle.com/wiki/Lossy_data_compression
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| | Learning-Theoretic Methods in Lossy Data Compression |
| | Thus lossy compression shares this common feature with other nonparametric learning scenarios: some unknown system generates data and the best action to be taken must be learned from these data. | | | As well, examples where the rate-distortion tradeoff approach of lossy compression proved fruitful in formalizing and solving learning problems will be pointed out. | | | In most practical situations, one has only limited information about the source generating the data, and an adequate (probabilistic) description of it must be learned from the data itself in order to choose a suitable compression algorithm. |
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http://www.pims.math.ca/industrial/2001/caims/Linder.html
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| | Partial Subtractive Dither for Lossy Data Compression |
| | To those skilled in the art of data compression, the use of subtractive dither to reduce the undesired quantization artifacts produced by lossy data-compression algorithms is well known. | | | The type of subtractive dither used heretofore, called "standard subtractive dither," involves a dither distribution that is uniform over a range equal to the quantization step size of the algorithm to which it is applied. | | | A technique of partial subtractive dither has been developed to improve the performance of any of a variety of near-lossless data-compression algorithms. |
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http://www.nasatech.com/Briefs/Mar01/NPO20964.html
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| | Avisoft Bioacoustics - Lossy Audio Data Compression Effects |
| | If the available bit rate is not sufficient for encoding a given signal, the data reduction algorithm has to remove those parts of the sound, that are inaudible or less important for the human perception. | | | The data rate of this uncompressed file is 705 kBit/s. | | | A simple digital reverberation filter was applied to the original uncompressed sound file in order to simulate a poor field recording.* It can be seen, that even without the influence of a lossy data reduction system, an emitted signal may be degraded by other effects too. |
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http://www.avisoft-saslab.com/compression.htm
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| | data compression |
| | Robert Maxwell Case http://www.YOUniverse.com/ has apparently patented a digital halftone method that is much friendlier to data compression algorithms, and a file format and image viewers to view it on lower-resolution, higher-depth displays. | | | program compression various ways to compress executable software, especially methods that create executable software that executes and runs similar to the original. | | | The compressed file header just stores the *lengths* of the codeword for each symbol, and the decompressor regenerates the code words from that. |
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http://www.rdrop.com/~cary/html/data_compression.html
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| | Untitled Document |
| | We were able to compress the data substantially, but the technique relied on our advance knowledge that there would be more male than female customers. | | | Suppose you are given a bmp file and you convert it to gif and then misplace the original bmp. | | | Suppose you are given a bmp file and you convert it to jpg and then misplace the original bmp. |
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http://www.vuw.ac.nz/scps-students/tech102/lectures/week11/11Mon/Summary_11_Mon.htm
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| | Bin Yu Lossy Data Compression |
| | Specifically, we present an algorithm where each coefficient is classified into several classes based on the past quantized data and where the quantizer to be used for each class can itself be adapted on the fly. | | | The Ph.D. thesis of Antonio Ortega with Vetterli in 1994 contained a novel algorithm which modifies the quantization levels of the incoming real data based on quantized past data. | | | The need for this type of algorithm can be envisioned in the transmission of a large quantity of images over the internet where both ends have free access only to quantized past data. |
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http://cm.bell-labs.com/cm/ms/departments/sia/binyu/aq.html
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| | Define lossless and lossy compression - a definition from Whatis.com - see also: lossy, lossless, lossy compression, ... |
| | This is generally the technique of choice for text or spreadsheet files, where losing words or financial data could pose a problem. | | | The JPEG image file, commonly used for photographs and other complex still images on the Web, is an image that has lossy compression. | | | On the other hand, lossy compression reduces a file by permanently eliminating certain information, especially redundant information. |
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http://whatis.techtarget.com/definition/0,,sid9_gci214453,00.html
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| | JumpGate Intro |
| | This compressed information is then sent to your computer and de-compressed. | | | The Accelerator software requires Windows 98 at a minimum for the e-mail compression feature, and Microsoft Internet Explorer version 5.0 at a minimum is required for the pop-up blocker feature. | | | Web page acceleration will work on any Windows web browser that supports proxy configuration (see our Support page for details). |
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http://www.elknet.net/jumpgate/works.html
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| | Bin Yu Lossy Data Compression |
| | The information theory ideas related to MDL belong to noiseless data compression, whereby redundancy is eliminated without loss of information. | | | Working with MDL for part of my thesis introduced me to information theory, and my research has become more involved in information theory since then. | | | looks at an old problem in rate-distortion theory: what is the universal redundancy rate for lossy data compression if the data are iid and discrete. |
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http://www.stat.berkeley.edu/users/binyu/rdt.html
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| | DataCompression.info - Lossy Compression |
| | Their home page advertises GeoEnergy as "The leader in fast data compression algorithms for the oil and gas industry." Quite a few algorithms are listed, all of which work on various types of collected seismic data. | | | A study of lossy compression algorithms, including discussion of JPEG, MPEG, and the DCT. | | | Ideally, when compression image or sound files, the loss is either minimal or undetectable by human observors. |
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http://datacompression.info/Lossy.shtml
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| | Lossy Data Compression, Fall 2005 |
| | The report may contain references (links) to data at your homepage which I may or may not look at. | | | All students in a group should participate actively in the presentations of the projects at all project sessions. | | | October 31th Basics of Digital Signal Processing: Signals, sampling and filtering. |
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http://www.daimi.au.dk/~bromille/DC05/lossy.html
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| | Lossy data compression and Tinnitus (Karan Anand ) |
| | There was valuable information for a tinnitus sufferer to consider in a documentary I had seen on ear damage focusing on this condition (Discovery channel). | | | I had a question and would be grateful if any 1 could help me. I am a dyslexic student studying audio engineering online and have allot of my text data read out to me through a Text-to-Speech application. | | | Dear List, Just recently there was a post on Ear damage due to exposure to lossy data compression of digital audio, and the linkage with Tinnitus. |
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http://www.auditory.org/postings/2003/5.html
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| | Bin Yu Lossy Data Compression |
| | Our results show that a small number of quantization levels achieves almost the same performance of full precision thresholding, suggesting that denoising is mainly due to the zero-zone and that the full precision of the thresholded coefficients is of secondary importance. | | | Chang, B. Yu and M. Vetterli,'' Bridging compression to wavelet thresholding as a denoising method,'' To appear in Proceedings of 1997 Conference on Information Sciences and Systems. | | | Some past work have shown lossy compression can be a good denoising tool. |
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http://cm.bell-labs.com/cm/ms/departments/sia/binyu/dc.html
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