Data compression system

A data compression system is described in which TV PCM data for each line scan is received in the form of a succession of multibit pixel words. All or selected bits of each word are compressed by providing difference values between successive pixel words and coding the difference values of a selected number of pixel words forming a block into a fundamental sequence (FS). The FS, based on its length and the number of words per block, is either transmitted as the compressed data or is used to generate a code FS or its complement is used to generate a code FS bar. When the code FS is generated, its length is compared with the original block PCM and only if the former is the shorter of the two is the code transmitted. Selected bits per pixel word may be compressed, while the remaining bits may be transmitted directly, or some of them may be omitted altogether

Mission science value-cost savings from the Advanced Imaging Communication System (AICS)

An Advanced Imaging Communication System (AICS) was proposed in the mid-1970s as an alternative to the Voyager data/communication system architecture. The AICS achieved virtually error free communication with little loss in the downlink data rate by concatenating a powerful Reed-Solomon block code with the Voyager convolutionally coded, Viterbi decoded downlink channel. The clean channel allowed AICS sophisticated adaptive data compression techniques. Both Voyager and the Galileo mission have implemented AICS components, and the concatenated channel itself is heading for international standardization. An analysis that assigns a dollar value/cost savings to AICS mission performance gains is presented. A conservative value or savings of $3 million for Voyager,$4.5 million for Galileo, and as much as $7 to 9.5 million per mission for future projects such as the proposed Mariner Mar 2 series is shown

The code word Wiggle - TV data compression

Information preserving data compression systems with coding algorithm developed for noiseless channel condition

RPV application of a globally adaptive rate controlled compressor

A globally adaptive image compression structure is introduced for use in a tactical RPV environment. The structure described would provide an operator with the flexibility to dynamically maximize the usefulness of a limited and changing data rate. The concepts would potentially simplify system design while at the same time improving overall system performance

Principles Of Differentiation And Morphogenesis

Developmental biology is the science connecting genetics with anatomy, making sense out of both. The body builds itself from the instructions of the inherited DNA and the cytoplasmic system that interprets the DNA into genes and creates intracellular and cellular networks to generation the observable phenotype. Even ecological factors such as diet and stress may modify the DNA such that different phenotypes can be constructed from the same DNA. During the past two decades, the basic principles of development have become known; although this brief chapter cannot do them justice (see, for example, Gilbert, 2013), they cover the following: mechanisms of differential gene expression; combinatorial logic of enhancers and promoters; signal-transduction pathways linking cell membrane and nucleus; mechanisms by which syndromes occur; the repertoire of morphogenetic interactions and the molecules causing them; environmental agents of phenotype production

Image data compression application to imaging spectrometers

The potential of image data compression techniques to satisfy the anticipated requirements of imaging spectrometer missions is discussed. Noiseless coding, rate controlled compression, cluster compression, and error protection are addressed

First-occurrence time of high-level crossings in a continuous random process

Statistical probability distribution of first occurrence and first recurrence times of given level crossing in continuous random proces

Some practical universal noiseless coding techniques, part 2

This report is an extension of earlier work (Part 1) which provided practical adaptive techniques for the efficient noiseless coding of a broad class of data sources characterized by only partially known and varying statistics (JPL Publication 79-22). The results here, while still claiming such general applicability, focus primarily on the noiseless coding of image data. A fairly complete and self-contained treatment is provided. Particular emphasis is given to the requirements of the forthcoming Voyager II encounters of Uranus and Neptune. Performance evaluations are supported both graphically and pictorially. Expanded definitions of the algorithms in Part 1 yield a computationally improved set of options for applications requiring efficient performance at entropies above 4 bits/sample. These expanded definitions include as an important subset, a somewhat less efficient but extremely simple "FAST' compressor which will be used at the Voyager Uranus encounter. Additionally, options are provided which enhance performance when atypical data spikes may be present

Signature extension using transformed cluster statistics and related techniques

There are no author-identified significant results in this report

Wheat productivity estimates using LANDSAT data

There are no author-identified significant results in this report