This paper proposes a novel entropy encoding technique for lossless data compression. Representing a message string by its lexicographic index in the permutations of its symbols results in a compressed version matching Shannon entropy of the message. Commercial data compression standards make use of Huffman or arithmetic coding at some stage of the compression process. In the proposed method, l...

This paper discusses the problem of using data compression for encryption. We first propose an algorithm for breaking a prefix-coded file by enumeration. Based on the algorithm, we respectively analyze the complexity of breaking Huffman codes and Shannon-Fano-Elias codes under the assumption that the cryptanalyst knows the code construction rule and the probability mass function of the source. ...

The domain “Sun Zip” will reduce the overall number of bits and bytes in a file. So, the files can be easily transmitted over slow internet connection and it takes a less space in disk. Domain sun zip is based on software. The software is done by java. It can use in the system as a utility. The type of compression we use here is lossless compression. The user doesn’t need to depend upon the thi...

With increasing amount of text data being stored rapidly, efficient information retrieval and Storage in the compressed domain has become a major concern. Compression is the process of coding that will effectively reduce the total number of bits needed to represent certain information. Data compression has been one of the critical enabling technologies for the ongoing digital multimedia revolut...

This paper represents the Algorithm for various Coding standards such as Huffman coding, Syntax based arithmetic coding and Context Adaptive Binary Arithmetic Coding used in MPEG, H.263 and H.264 respectively and their analysis. We found that average bit per symbol (average code word length) for Huffman coding is nearly equal to Entropy which is the basic requirement, for different bit rate PSN...

There are several data compression Techniques available which are used for Efficient transmission and storage of the data With less memory space. In this paper, we have Proposed a two stage data compression Algorithm that is OLZWH which uses the Optimality of LempelZiv-Welch (OLZW) and Adaptive Huffman Coding. With this proposed Algorithm, the data Compression ratios are Compared with existing ...

The demand for handling images in digital form has increased dramatically in recent years. Image compression is an effective technique of reducing or less the amount of image information that are required to represent/show an image in better format ,after compression image size get reduced.The objective of image compression is to reduce the amount of digital images information and therefore red...

Data compression plays an important role in multimedia communication. A major compression technique is performed by converting the fixed-length codes to variable-length codes. Huffman coding is demonstrated to be a very efficient coding scheme and has been widely adopted. However, the variable-length codes increase the difficulties of fast decoding. In addition, the variable decoding time is no...