The paper describes an efficient lossy and lossless three dimensional (3D) image compression of hyperspectral images. The method adopts the 3D spatial-spectral hybrid transform and the proposed transform-based coder. The hybrid transforms are that Karhunen-Loève Transform (KLT) which decorrelates spectral data of a hyperspectral image, and the integer Discrete Wavelet Transform (DWT) which is a...

Image steganography using Discrete Wavelet Transform can attain very good results as compared to traditional methods, in this paper we discuss a method to embed digital watermark based on modifying frequency coefficient in discrete wavelet transform (DWT) domain. This method uses the embedded zero-tree (EZW) algorithm to insert a watermark in discrete wavelet transform domain. EZW is an effecti...

This work presents an electrocardiogram (ECG) compression processor for wireless sensors with configurable data lossless and lossy compression. Lifting wavelet transforms of 9/7-M and 5/3 are employed for signal decomposition instead of traditional wavelet. A hybrid encoding scheme improves compression efficiency by encoding the higher scales of decomposed coefficients with modified embedded ze...

According to the high and low frequency distribution characteristics of wavelet coefficients that were given by Wavelet transform decomposition of images, in this paper, a improved algorithm was proposed for the disadvantage of the classic EZW. The improved algorithm included four steps to improve the coding efficiency of EZW: to predict low-frequency sub-band coding and code after move the for...

Technically, all image data compression schemes can be categorized into two groups as lossless (reversible) and lossy (irreversible). Although some information is lost in the lossy compression, especially for the radiologic image compression, new algorithms can be designed to minimize the effect of data loss on the diagnostic features of the images. Wavelet transform (WT) constitute a new compr...

—Multimedia network systems require image and video compression schemes in order to efficiently take profit from the available bandwidth. In this paper, we present a wavelet still-image coder, called LTW (Lower-Tree Wavelet), based on the construction and codification of coefficient trees as other proposals do. This algorithm is fast and symmetric (except in extremely low bit rates), which make...

The Set Partitioning in Hierarchical Trees (SPIHT) approach for still image compression is one of the most efficient embedded gray image compression schemes till date. The algorithm relies on a very efficient scanning cum bit-allocation scheme for quantizing the coefficients obtained by a wavelet decomposition of an image. In this paper, modifications of the SPIHT compressor without arithmetic ...