In this report, a digital image data compression method which has two modes – “losslesss” mode and “lossy” mode – and also “progressive” functionality is proposed. The coding system can be optimized for an arbitrary input image signal under the lossless / lossy unified coding gain introduced here.

The advantages of digitizing medical radiographs are twofold. First, they can be transmitted via networks, second, they may be archived on appropriate storage devices. Modern equipment for medical imaging already provides digital images, therefore post-digitization can be discarded. Depending on medical investigation the amount of image data to be stored can be very large. As a consequence digi...

A new color image watermarking algorithm with resistance to JPEG lossy compression based on Quantization Index Modulation (QIM) is proposed in this paper. As it is known, QIM method can achieve a good balance between the embedding bit rate, robustness and distortion between the original image and the composited image by modulating the source signal into different clusters. The corresponding DCT...

In the paper is presented one new approach for adaptive processing and compression of images of scanned documents, which contain text and pictures. In order to achieve high compression with maximum retained quality, the document content is analyzed and two corresponding regions of interest are set. Then, each region is processed as follows: the text – with lossless and the picture – with lossy ...

A novel source-reverse transform for digital images is presented for image structure representation and analysis based on an electro-static analogy. In this transform, the image is taken as the potential field and the virtual source is reversed imitating the Gauss’s law. Region border detection is implemented based on the virtual field source representation of image structure. Moreover, the ene...

Several techniques have been developed for modifying the JPEG standard lossy compression algorithm in order to improve image quality, and two of them are discussed in this report. Also, since these techniques have mainly been evaluated in terms of peak signal-to-noise ratio (PSNR), which is an outdated image quality metric (IQM), the topic of image quality assessment is investigated. Finally, t...

Lossy compression of hyperspectral imagery is considered with special emphasis on the preservation of anomalous pixels. In the proposed scheme, anomalous pixels are extracted before compression and replaced with interpolation from surrounding, non-anomalous pixels. The image is then coded using principal component analysis for spectral decorrelation followed by JPEG2000. The anomalous pixels do...

This article presents a polynomial-based image compression scheme, which consists of using the color model (YUV) to represent contents and two-dimensional polynomial coding (first-order) with variable block size according correlation between neighbor pixels. The residual part for all bands is analyzed into two parts, most important (big) part, least (small) parts. Due significant subjective imp...

Digital images have become an important source of information in the modern world of communication systems. In their raw form, digital images require a tremendous amount of memory. Many research efforts have been devoted to the problem of image compression in the last two decades. Two different compression categories must be distinguished: lossless and lossy. Lossless compression is achieved if...

An integer reversible implementation of multiple component transform is significant for lossless, unified lossy/lossless and progressive lossy-lossless multi-component or hyper-spectral image coding. In this proposal, we present a reversible integer mapping method for invertible linear transforms. Its effectiveness was evaluated using 2 6-band Landsat TM images and an 80-component hyper-spectra...