Compressing an image is significantly different than compressing raw binary data. For this different compression algorithm are used to compress images. Discrete wavelet transform has been widely used to compress the image. Wavelet transform are very powerful compared to other transform because its ability to describe any type of signals both in time and frequency domain simultaneously. The prop...

The necessity in medical image compression continuously grows during the last decade. In advanced medical life large number of medical images is processed in hospitals and medical centers around the world. These images are in the form of sequences which are much correlated and are of great importance. Hence lossless image compression is needed to reproduce the original quality of the image with...

Data compression and cryptography play an important role when transmitting data across a public computer network. While compression reduces the amount of data to be transferred or stored, cryptography ensures that data is transmitted with reliability and integrity. Compression and encryption have to be applied in the correct way: data are compressed before they are encrypted. If it were the opp...

We present an order-preserving general purpose data structure for binary data, the LPC-trie. The structure is a highly compressed trie, using both level and path compression. The memory usage is similar to that of a balanced binary search tree, but the expected average depth is smaller. The LPC-trie is well suited to modern language environments with eecient memory allocation and garbage collec...

The latter-day H.265/HEVC video compression standard is able to provide two-times higher compression efficiency compared to the current industrial standard, H.264/AVC. However, coding complexity also increased. The main bottleneck of the compression process is the rate-distortion optimization (RDO) stage, as it involves numerous sequential syntax-based binary arithmetic coding (SBAC) loops. In ...

In this paper a competitive neural network with binary synaptic weights is proposed. The aim of this network is to cluster or categorize binary input data. The neural network uses a learning mechanism based on activity levels that generates new binary synaptic weights that become medianoids of the clusters or categorizes that are being formed by process units of the network, since the medianoid...

We present work-optimal PRAM algorithms for Burrows-Wheeler compression and decompression of strings over a constant alphabet. For a string of length n, the depth of the compression algorithm is O(log n), and the depth of the the corresponding decompression algorithm is O(log n). These appear to be the first polylogarithmic-time work-optimal parallel algorithms for any standard lossless compres...

This paper presents a method of contour extraction and compression from grey level image. The proposed algorithm is applied in spectral domain using single-level wavelet transform (WT). Single step parallel contour extraction (SSPCE) method is used for the binary image after inverse wavelet transform is applied to the details images. Then the contours are compressed using either Ramer or Trapez...

Adaptive Binary Arithmetic coding is an effective mode of coding. In this paper we propose an efficient adaptive binary arithmetic coder, which is multiplication-free and look-up table free. To achieve this, we combine the probability estimation based on the virtual sliding window technique with the approximation of multiplication and the use of simple operations to calculate the next approxima...

Communication between a sender and receiver needs security. It can be done in any form, like plain text or binary data. Changing the information to some unidentifiable form, can save it from assailants. For example, plain text can be coded using schemes so that a stranger cannot apprehend it. Cryptography is a subject or field which deals with the secret transmission of messages/ data between t...