Hyperspectral sounding data requires accuracy for useful retrieval of atmospheric temperature, moisture, trace gases, clouds, aerosols and surface properties. Therefore, compression of hyperspectral sounding data is better to be lossless or near lossless. Given the large volume of three-dimensional hyperspectral data that will be generated by the hyperspectral sounders such as AIRS, CrIS, IASI,...

Pattern matching in compressed image domain is a new topic in computer science. Many works have been reported for pattern matching for compressed text and for lossy compressed image. However, searching of images in lossless compressed domain is almost a blank area and needs to be explored. Lossless image compression is widely used in areas such as medical images, satellite images, geometric ima...

Image compression is a well-established and extensively researched field. The huge interest in it has been aroused by the rapid enhancements introduced in imaging techniques and the various applications that use high-resolution images (e.g. medical, astronomical, Internet applications). The image compression algorithms should not only give state-of-art performance, they should also provide othe...

To improve the lossless compression ratios for images having sparse histograms, a method of histogram packing was introduced. The method was found to be effective for low bit depth images. We investigate effects of packing histograms of high bit depth images—medical CR, CT, and MR images as well as various natural 16-bit ones. We analyze an off-line packing method, which requires encoding the o...

In this study we evaluate the performance of several lossless grayscale image compression algorithms: algorithms that are standards in medical image transmitting and archiving systems, other algorithms used for compressing medical images in practice and in image compression research, and of a couple of universal algorithms applied to raw and preprocessed image data. In the experiments we use a ...

| This paper presents a lossless block-transform coder based on the Hadamard transform that achieves a compression ratio as good as that of the current lossless JPEG-standard and about 10 to 20% lower than the currently best state-of-the-art technique Calic. The main advantage of the proposed technique is that it produces an embedded data stream which may be truncated to achieve lossy compressi...

Arithmetic encoders enable the best compressors both for bi-level images (JBIG) and for grey scale and color images (CALIC), but they are often ruled out because too complex. The compression gap between simpler techniques and state of the art compressors can be significant. Storer extended dictionary text compression to bi-level images to avoid arithmetic encoders (BLOCK MATCHING), achieving 70...

This paper is a revised version of the paper with the same title in the proceedings of ICIP97 (which contains a serious error in g. 1 and in table 1). Abstract This paper presents a lossless block-transform coder based on the Hadamard transform that achieves a compression ratio as good as that of the current lossless JPEG-standard and about 10 to 20% lower than the currently best state-of-the-a...