introduction to data compression

... of these factors, namely data compression It explains why data can be compressed, it outlines the principles of the various approaches to compressing data, and it describes several compression ... approach to lossy compression The idea is to start with a finite list of N symbols Si and to modify each of the original data symbols to the nearest Si For example, if the original data consists ... Split-Merge on www.verypdf.com to remove this watermark David Salomon A Concise Introduction to Data Compression Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark Professor...

Ngày tải lên: 14/12/2013, 15:15

... asymmetric compression method) It reads the next input item and determines whether it is a token or raw data A token is used to obtain data from the dictionary and write it on the output Raw data is ... Compare X to its successors in the tree (from left to right and bottom to top) If the immediate successor has frequency F + or greater, the nodes are still in sorted order and there is no need to change ... long time to end up with long strings in the dictionary, and thus with a chance to achieve really good compression We say that LZW adapts slowly to its input data Exercise 3.3: Use LZW to encode...

Ngày tải lên: 14/12/2013, 15:15

... continuous-tone images, and for discrete-tone images There are also methods that try to break an image up into continuous-tone and discrete-tone parts, and compress each separately 5.1 Introduction ... ashamed to tell you to how many figures I carried these computations, having no other business at that time —Isaac Newton To figure out the kind of compression achieved by arithmetic coding, we have to ... order to remove ambiguity, the term “edoc” is used here to refer to them Each edoc is converted to a prefix code that’s output The first table allocates edocs through 255 to the literals, edoc 256 to...

Ngày tải lên: 14/12/2013, 15:15

... wavelet transform is the tool used in practice to analyze digital data and compress it The wavelet transform is a tool that cuts up data or functions or operators into different frequency components, ... ratios lead to better compression but may result in poorly reconstructed images The sparseness ratio is distantly related to the compression factor, a compression measure defined in the Introduction ... compressed in a single left -to- right, top -to- bottom scan; (b) progressive mode where the image is compressed in multiple blocks (known as “scans”) to be viewed from coarse to fine detail; (c) lossless...

Ngày tải lên: 14/12/2013, 15:15

... continuous-tone, discrete-tone, and cartoon-like It then states the main principle of image compression, a principle that stems from the correlation of pixels Eight approaches to image compression ... computer users long to realize that a computer can also store and process nonnumeric data The term “multimedia,” which became popular in the 1990s, refers to the ability to digitize, store, and manipulate ... audio file, we often want to listen to it while it is decompressed (in fact, we decompress it only in order to listen to it) This is why audio compression methods tend to be asymmetric The encoder...

Ngày tải lên: 14/12/2013, 15:15

... “predict” (to assign probabilities to) the data to be compressed This concept is important in statistical data compression When a statistical method is used, a model for the data has to be constructed ... Lossless Compression A compression method where the output of the decoder is identical to the original data compressed by the encoder (See also Lossy Compression. ) Lossy Compression A compression ... grayscale compression) , 43 color space, 184 companding, 14 companding (audio compression) , 229–231 compression factor, 17, 273 compression gain, 17, 273 compression performance measures, 16–17 compression...

Ngày tải lên: 14/12/2013, 15:15

... “predict” (to assign probabilities to) the data to be compressed This concept is important in statistical data compression When a statistical method is used, a model for the data has to be constructed ... Lossless Compression A compression method where the output of the decoder is identical to the original data compressed by the encoder (See also Lossy Compression. ) Lossy Compression A compression ... grayscale compression) , 43 color space, 184 companding, 14 companding (audio compression) , 229–231 compression factor, 17, 273 compression gain, 17, 273 compression performance measures, 16–17 compression...

Ngày tải lên: 14/12/2013, 15:15

... Compressed data can only be understood if the decoding method is known by the receiver ?Why Data Compression • Data storage and transmission cost money This cost increases with the amount of data ... design of data compression schemes therefore involve trade-offs between various factors, including the degree of compression, the amount of distortion introduced (if using a lossy compression ... be reduced by processing the data so that it takes less memory and less transmission time • Disadvantage of Data compression: Compressed data must be decompressed to be viewed (or heard), thus...

Ngày tải lên: 22/10/2015, 17:09

... expect It’s up to you, as a developer, to decide how you expect them to occur and to use transactions to meet your goals CHAPTER ■ INTRODUCTION TO DATA ACCESS • Network connections to database systems ... important to fix These categories apply whenever you write data- access code To our knowledge, all data- access tools available today can be affected by any of these categories Database Resources Data- access ... invoices to its work The database stores all members and all invoices It must be possible to get a list of all CHAPTER ■ INTRODUCTION TO DATA ACCESS invoices per member, which means the database...

Ngày tải lên: 05/10/2013, 04:20

... Module 1: Introduction to Data Warehousing and OLAP ! Organizes data into non-volatile, subject-specific groups A data warehouse stores data as non-volatile, subject-oriented data sets A data warehouse ... as their data sources Customer_Dim Customer_Dim ShipperKey ShipperKey ShipperID ShipperID CustomerKey CustomerKey CustomerID CustomerID To facilitate data retrieval and analysis, a data warehouse ... Storage Data Storage Relational Relational Data Structure Data Structure N-dimensional N-dimensional Data structure Data structure Data Content Data Content Detailed and Detailed and Summarized Data...

Ngày tải lên: 21/12/2013, 19:15

... 17: Introduction to Data Mining Data Mining Models Topic Objective To describe different data mining models and how they apply to data analysis ! Analysis Services Models Lead-in A variety of data ... Module 17: Introduction to Data Mining 19 Selecting Training Data Topic Objective To review the meaning of training data and demonstrate how to select training data Lead-in What is training data? ... Introduction to Data Mining Overview Topic Objective To provide an overview of the module topics and objectives ! Introducing Data Mining Lead-in ! Training a Data Mining Model ! Building a Data...

Ngày tải lên: 24/01/2014, 19:20

... better, customized services for an edge (e.g in Customer Relationship Management) © Tan,Steinbach, Kumar Introduction to Data Mining Why Mine Data? Scientific Viewpoint Data collected and stored at ... analysis, by automatic or semi-automatic means, of large quantities of data in order to discover meaningful patterns © Tan,Steinbach, Kumar Introduction to Data Mining What is (not) Data Mining? ... © Tan,Steinbach, Kumar Total Articles 555 354 278 Introduction to Data Mining 19 Clustering of S&P 500 Stock Data Observe Stock Movements every day Clustering points: Stock-{UP/DOWN} Similarity...

Ngày tải lên: 15/03/2014, 09:20

... Kumar Introduction to Data Mining Types of data sets Record – Data Matrix – Document Data – Transaction Data Graph – World Wide Web – Molecular Structures Ordered – Spatial Data – Temporal Data ... Tan,Steinbach, Kumar Introduction to Data Mining 19 Ordered Data Spatio-Temporal Data Average Monthly Temperature of land and ocean © Tan,Steinbach, Kumar Introduction to Data Mining 20 Data Quality ... and Dense Linear System Solvers Introduction to Data Mining 16 Chemical Data Benzene Molecule: C6H6 © Tan,Steinbach, Kumar Introduction to Data Mining 17 Ordered Data Sequences of transactions...

Ngày tải lên: 15/03/2014, 09:20

... object Introduction to Data Mining separate face becomes a Star Plots for Iris Data Setosa Versicolour Virginica © Tan,Steinbach, Kumar Introduction to Data Mining 29 Chernoff Faces for Iris Data ... Tan,Steinbach, Kumar Introduction to Data Mining 35 OLAP Operations: Data Cube The key operation of a OLAP is the formation of a data cube A data cube is a multidimensional representation of data, together ... two slides © Tan,Steinbach, Kumar Introduction to Data Mining 23 Visualization of the Iris Data Matrix standard deviation © Tan,Steinbach, Kumar Introduction to Data Mining 24 Visualization of...

Ngày tải lên: 15/03/2014, 09:20

... same data! 10 © Tan,Steinbach, Kumar Introduction to Data Mining Decision Tree Classification Task Decision Tree © Tan,Steinbach, Kumar Introduction to Data Mining Apply Model to Test Data Test Data ... that belong to more than one class, use an attribute test to split the data into smaller subsets Recursively apply the procedure to each subset © Tan,Steinbach, Kumar Introduction to Data Mining ... Determine how to split the records • How to specify the attribute test condition? • How to determine the best split? – Determine when to stop splitting © Tan,Steinbach, Kumar Introduction to Data Mining...

Ngày tải lên: 15/03/2014, 09:20

... (2) and (3) until stopping criterion is met © Tan,Steinbach, Kumar Introduction to Data Mining 14 Example of Sequential Covering (ii) Step © Tan,Steinbach, Kumar Introduction to Data Mining 15 Example ... Step Introduction to Data Mining 16 Aspects of Sequential Covering Rule Growing Instance Elimination Rule Evaluation Stopping Criterion Rule Pruning © Tan,Steinbach, Kumar Introduction to Data ... that have the k smallest distance to x © Tan,Steinbach, Kumar Introduction to Data Mining 39 nearest-neighbor Voronoi Diagram © Tan,Steinbach, Kumar Introduction to Data Mining 40 Nearest Neighbor...

Ngày tải lên: 15/03/2014, 09:20

... Pointer to projected database of its ancestor node – Bitvector containing information about which transactions in the projected database contain the itemset © Tan,Steinbach, Kumar Introduction to Data ... support © Tan,Steinbach, Kumar Introduction to Data Mining 12 Illustrating Apriori Principle Found to be Infrequent Pruned supersets © Tan,Steinbach, Kumar Introduction to Data Mining 13 Illustrating ... (NM) – Use efficient data structures to store the candidates or transactions – No need to match every candidate against every transaction © Tan,Steinbach, Kumar Introduction to Data Mining 11 Reducing...

Ngày tải lên: 15/03/2014, 09:20

... 7, 8, 1, 1, 1, 8, Introduction to Data Mining 26 Examples of Sequence Data Sequence Database Sequence Element (Transaction) Event (Item) Customer Purchase history of a given customer A set of items ... need to perform more passes over the data – May miss some potentially interesting cross© Tan,Steinbach, Kumar Introduction to Data Mining 25 level association patterns Sequence Data Sequence Database: ... Kumar Introduction to Data Mining 20 Multi-level Association Rules Food Electronics Bread Computers Milk Wheat Skim White Foremost © Tan,Steinbach, Kumar 2% Desktop Kemps Introduction to Data...

Ngày tải lên: 15/03/2014, 09:20

... Tan,Steinbach, Kumar Introduction to Data Mining Notion of a Cluster can be Ambiguous How many clusters? Six Clusters Two Clusters Four Clusters © Tan,Steinbach, Kumar Introduction to Data Mining Types ... hierarchical tree © Tan,Steinbach, Kumar Introduction to Data Mining Partitional Clustering Original Points © Tan,Steinbach, Kumar A Partitional Clustering Introduction to Data Mining Hierarchical Clustering ... Tan,Steinbach, Kumar Introduction to Data Mining 18 Clustering Algorithms K-means and its variants Hierarchical clustering Density-based clustering © Tan,Steinbach, Kumar Introduction to Data Mining 19...

Ngày tải lên: 15/03/2014, 09:20

... Kumar Introduction to Data Mining 17 Experimental Results: CHAMELEON © Tan,Steinbach, Kumar Introduction to Data Mining 18 Experimental Results: CHAMELEON © Tan,Steinbach, Kumar Introduction to Data ... (c) and (d) Introduction to Data Mining 13 Chameleon: Clustering Using Dynamic Modeling Adapt to the characteristics of the data set to find the natural clusters Use a dynamic model to measure ... Rastogi, Shim © Tan,Steinbach, Kumar Introduction to Data Mining Experimental Results: CURE (centroid) (single link) Picture from CURE, Guha, Rastogi, Shim © Tan,Steinbach, Kumar Introduction to...

Ngày tải lên: 15/03/2014, 09:20