Fractal image coding has the advantage of higher compression ratio, but is a lossy compression scheme. The encoding procedure consists of dividing the image into range blocks and domain blocks and then it takes a range block and matches it with the domain block. The image is encoded by partitioning the domain block and using Affine transformation to achieve fractal compression. The image is rec...

In this work, a subband domain textual image compression method is developed. The document image is first decomposed into subimages using binary subband decompositions. Next, the character locations in the subbands and the symbol library consisting of the character images are encoded. The method is suitable for keyword search in the compressed data. It is observed that very high compression rat...

Although there have been many compression schemes for reducing data effectively, most schemes do not consider the reordering of data. In the case of unordered data, if the users change the data order in a given data set, the compression ratio may be improved compared to the original compression before reordering data. However, in the case of ordered data, the users need a mapping table that map...

Compression is used just about everywhere. Reduction of both compression ratio and retrieval of data from large collection is important in today‟s era. We propose a pre-compression technique that can be applied to text files. The output of our technique can be further applied to standard compression techniques available, such as arithmetic coding and BZIP2, which yields in better compression ra...

This paper presents a new data compression concept, “on-board processing,” for infrared astronomy, where space observatories have limited processing resources. The proposed approach has been developed and tested for the PACS camera from the European Space Agency (ESA) mission, Herschel. Using lossy and lossless compression, the presented method offers high compression ratio with a minimal loss ...

Imaging applications generate large volumes of data leading to challenges for transmission and storage. In this paper a novel hybrid image compression technique for efficient storage and delivery of data is proposed. It is based on decomposing the data using daubechies-4 wavelet in combination with the lifting scheme and entropy encoding. This scheme is concerned with the compression ratio, bit...

Compression is used just about everywhere. Reduction of both compression ratio and retrieval of data from large collection is important in today‟s era. We propose a pre-compression technique that can be applied to text files. The output of our technique can be further applied to standard compression techniques available, such as arithmetic coding and BZIP2, which yields in better compression ra...

Electrocardiogram (ECG) signal compression is playing a vital role in biomedical applications. The signal compression is meant for detection and removing the redundant information from the ECG signal. This paper proposes a new technique of ECG compression using Wavelet packet transform methods up to 4th level of decomposition. The quality measurement of the reconstructed signal in an electrocar...