In 1994 Burrows and Wheeler [5] described a universal data compression algorithm (BW-algorithm, for short) which achieved compression rates that were close to the best known compression rates. Due to it’s simplicity, the algorithm can be implemented with relatively low complexity. Fenwick [8] described ideas to improve the efficiency (i.e. the compression rate) and complexity of the BW-algorith...

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 ...

In this paper we present a novel approach for wavelet compression of electrocardiogram (ECG) signals based on the set partitioning in hierarchical trees (SPIHT) coding algorithm. SPIHT algorithm has achieved prominent success in image compression. Here we use a modified version of SPIHT for one dimensional signals. We applied wavelet transform with SPIHT coding algorithm on different records of...

This paper deals with the predictive compression of images using neural networks (NN). The idea is to use of the backpropagation algorithm in order to compute the predicted pixels. The results validation is performed by comparison with linear prediction compression used in JPEG algorithm. Key-Words: lossless image compression, neural networks, prediction, backpropagation algorithm

This paper presents a new LZW data compression algorithm that partitions conventional single large dictionary into a dictionary set that consists of several small address space dictionaries. As doing so the dictionary set not only has small lookup time but also can operate in parallel. Simulation results show that the proposed algorithm has better compression ratio for image data than conventio...

Image compression is the application of Data compression on digital images. In DCT-based compression standards such as conventional JPEG algorithm, an image is divided into eight-by-eight blocks and then the 2-D Discrete cosine transform (DCT) is applied to encode each block. Another DCT based algorithm called as Modified JPEG compression algorithm [1], overcomes the limitations of conventional...

The Wide Field Camera in the Advanced Camera for Surveys (ACS) produces very large 4096× 4096 pixel images. We will have on-board image compression in order to reduce both the storage requirements at the telescope and the time to transmit the data to the ground. This is the first time on-board compression has been included in an Hubble Space Telescope instrument. We have developed a new lossles...

In this paper a novel algorithm for lossless compression of volumetric data is presented. This algorithm is based on our previously presented algorithm for lossless compression of volumetric data, which uses quadtree encoding of slices of data for discovering the coherence and similarities between consecutive slices. By exploiting these properties of the data, the algorithm can efficiently comp...

In this paper we present Linear Transformation Algorithm (LTA), which is based on a new transformation, Linear Block Transformation (LOT). Experimental results show that Linear Transformation Algorithm yields comparable results to Burrows-Wheeler Algorithm (BWA) [4] and outperforms Gzip, and Shorten Waveform Coder for nearlossless ECG compression; for lossless ECG compression it yields better c...

Parallel image compression on a workstation-cluster is discussed. We introduce a parallel meta-algorithm for image compression which is well suited for every block based image compression scheme. This algorithm is explained in more detail in the case of fractal image compression. We present experimental results of a host/node implementation on a FDDI interconnected workstationcluster using PVM.