Multimedia applications require a compression and decompression scheme for digital video. The standardized and widely used techniques JPEG and MPEG provide very good compression ratios, but are computationally quite complex and demanding. We propose to use an extension to the much simpler Color Cell Compression scheme as an alternative. Our extension includes the use of variable block sizes, th...

ÐA very interesting recent development in data compression is the Burrows-Wheeler Transformation [1]. The idea is to permute the input sequence in such a way that characters with a similar context are grouped together. We provide a thorough analysis of the Burrows-Wheeler Transformation from an information theoretic point of view. Based on this analysis, the main part of the paper systematicall...

MPEG-4 is a method of defining compression of audio and video digital data. MPEG-4 videos double compression method is used to decompress video from spatial domain to the frequency domain and then resaved with a different quantization matrix. Markov feature is a second order statistics which was adopted to detect double compression artifacts in the original video. In proposed system, double com...

Hospitals and clinical environments are moving towards computerization, digitization and centralization, resulting in prohibitive amounts of digital medical images. Advance in telecommunication and information technology and emergence of electronic management systems are other reasons that resonating image problems. Therefore, Compression techniques are essential in archival and communication o...

Given a text, grammar-based compression is to construct a grammar that generates the text. There are many kinds of text compression techniques of this type. Each compression scheme is categorized as being either off-line or on-line, according to how a text is processed. One representative tactics for off-line compression is to substitute the longest repeated factors of a text with a production ...

The compression is a vital field in image processing which reduces the bandwidth during data transfer in multimedia communications. In this paper, we propose Image Compression using Self Organizing Map (SOM) and Discrete Wavelet Transform (DWT) with Error Correction. The input image is considered from standard database and modified to 4x4 blocks and rearranged as 16x4096 input vectors and appli...

BACKGROUND frequency compression. AIM to evaluate the index of speech recognition (IPRF) using frequency compression in three different ratios. METHODS monosyllabic words were recorded using an algorithm of frequency compression in three ratios: 1:1, 2:1, 3:1, generating three lists of words. Eighteen listeners accomplished the IPRF using the modified words. They were subdivided in two grou...

Database compression and decompression is a susceptible problem in the database framework. Database compression is widely used in data management to improve the performance and save storage space. When you have large amounts of data, the cost of the storage subsystem can easily exceed the cost of your data server. Over the last decades, improvements in CPU speed have outpaced improvements in ma...

The B-tree and its variants have been widely applied in many data management fields. When a compression of these data structures is considered, we follow two objectives. The first objective is a smaller index file, the second one is a reduction of the query processing time. In this paper, we apply a compression scheme to fit these objectives. The utilized compression scheme handles compressed n...