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CURRENT STATUS OF DATA COMPRESSION IN TELEMETRYHoran, Sheila B. 10 1900 (has links)
International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California / Reduction of bandwidth for signal transmission is of paramount concern to many in the telemetry and wireless industry. One way to reduce bandwidth is to reduce the amount data being sent. There are several techniques available to reduce the amount of data. This paper will review the various types of data compression currently in use for telemetry data and how much compression is achieved.
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Context-based compression algorithms for text and image data.January 1997 (has links)
Wong Ling. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (leaves 80-85). / ABSTRACT --- p.1 / Chapter 1. --- INTRODUCTION --- p.2 / Chapter 1.1 --- motivation --- p.4 / Chapter 1.2 --- Original Contributions --- p.5 / Chapter 1.3 --- thesis Structure --- p.5 / Chapter 2. --- BACKGROUND --- p.7 / Chapter 2.1 --- information theory --- p.7 / Chapter 2.2 --- early compression --- p.8 / Chapter 2.2.1 --- Some Source Codes --- p.10 / Chapter 2.2.1.1 --- Huffman Code --- p.10 / Chapter 2.2.1.2 --- Tutstall Code --- p.10 / Chapter 2.2.1.3 --- Arithmetic Code --- p.11 / Chapter 2.3 --- modern techniques for compression --- p.14 / Chapter 2.3.1 --- Statistical Modeling --- p.14 / Chapter 2.3.1.1 --- Context Modeling --- p.15 / Chapter 2.3.1.2 --- State Based Modeling --- p.17 / Chapter 2.3.2 --- Dictionary Based Compression --- p.17 / Chapter 2.3.2.1 --- LZ-compression --- p.19 / Chapter 2.3.3 --- Other Compression Techniques --- p.20 / Chapter 2.3.3.1 --- Block Sorting --- p.20 / Chapter 2.3.3.2 --- Context Tree Weighting --- p.21 / Chapter 3. --- SYMBOL REMAPPING --- p.22 / Chapter 3. 1 --- reviews on Block Sorting --- p.22 / Chapter 3.1.1 --- Forward Transformation --- p.23 / Chapter 3.1.2 --- Inverse Transformation --- p.24 / Chapter 3.2 --- Ordering Method --- p.25 / Chapter 3.3 --- discussions --- p.27 / Chapter 4. --- CONTENT PREDICTION --- p.29 / Chapter 4.1 --- Prediction and Ranking Schemes --- p.29 / Chapter 4.1.1 --- Content Predictor --- p.29 / Chapter 4.1.2 --- Ranking Techn ique --- p.30 / Chapter 4.2 --- Reviews on Context Sorting --- p.31 / Chapter 4.2.1 --- Context Sorting basis --- p.31 / Chapter 4.3 --- General Framework of Content Prediction --- p.31 / Chapter 4.3.1 --- A Baseline Version --- p.32 / Chapter 4.3.2 --- Context Length Merge --- p.34 / Chapter 4.4 --- Discussions --- p.36 / Chapter 5. --- BOUNDED-LENGTH BLOCK SORTING --- p.38 / Chapter 5.1 --- block sorting with bounded context length --- p.38 / Chapter 5.1.1 --- Forward Transformation --- p.38 / Chapter 5.1.2 --- Reverse Transformation --- p.39 / Chapter 5.2 --- Locally Adaptive Entropy Coding --- p.43 / Chapter 5.3 --- discussion --- p.45 / Chapter 6. --- CONTEXT CODING FOR IMAGE DATA --- p.47 / Chapter 6.1 --- Digital Images --- p.47 / Chapter 6.1.1 --- Redundancy --- p.48 / Chapter 6.2 --- model of a compression system --- p.49 / Chapter 6.2.1 --- Representation --- p.49 / Chapter 6.2.2 --- Quantization --- p.50 / Chapter 6.2.3 --- Lossless coding --- p.51 / Chapter 6.3 --- The Embedded Zerotree Wavelet Coding --- p.51 / Chapter 6.3.1 --- Simple Zerotree-like Implementation --- p.53 / Chapter 6.3.2 --- Analysis of Zerotree Coding --- p.54 / Chapter 6.3.2.1 --- Linkage between Coefficients --- p.55 / Chapter 6.3.2.2 --- Design of Uniform Threshold Quantizer with Dead Zone --- p.58 / Chapter 6.4 --- Extensions on Wavelet Coding --- p.59 / Chapter 6.4.1 --- Coefficients Scanning --- p.60 / Chapter 6.5 --- Discussions --- p.61 / Chapter 7. --- CONCLUSIONS --- p.63 / Chapter 7.1 --- Future Research --- p.64 / APPENDIX --- p.65 / Chapter A --- Lossless Compression Results --- p.65 / Chapter B --- Image Compression Standards --- p.72 / Chapter C --- human Visual System Characteristics --- p.75 / Chapter D --- Lossy Compression Results --- p.76 / COMPRESSION GALLERY --- p.77 / Context-based Wavelet Coding --- p.75 / RD-OPT-based jpeg Compression --- p.76 / SPIHT Wavelet Compression --- p.77 / REFERENCES --- p.80
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Entropy coding and post-processing for image and video coding.January 2010 (has links)
Fong, Yiu Leung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 83-87). / Abstracts in English and Chinese. / Abstract --- p.2 / Acknowledgement --- p.6 / Chapter 1. --- Introduction --- p.9 / Chapter 2. --- Background and Motivation --- p.10 / Chapter 2.1 --- Context-Based Arithmetic Coding --- p.10 / Chapter 2.2 --- Video Post-processing --- p.13 / Chapter 3. --- Context-Based Arithmetic Coding for JPEG --- p.16 / Chapter 3.1 --- Introduction --- p.16 / Chapter 3.1.1 --- Huffman Coding --- p.16 / Chapter 3.1.1.1 --- Introduction --- p.16 / Chapter 3.1.1.2 --- Concept --- p.16 / Chapter 3.1.1.3 --- Drawbacks --- p.18 / Chapter 3.1.2 --- Context-Based Arithmetic Coding --- p.19 / Chapter 3.1.2.1 --- Introduction --- p.19 / Chapter 3.1.2.2 --- Concept --- p.20 / Chapter 3.2 --- Proposed Method --- p.30 / Chapter 3.2.1 --- Introduction --- p.30 / Chapter 3.2.2 --- Redundancy in Quantized DCT Coefficients --- p.32 / Chapter 3.2.2.1 --- Zig-Zag Scanning Position --- p.32 / Chapter 3.2.2.2 --- Magnitudes of Previously Coded Coefficients --- p.41 / Chapter 3.2.3 --- Proposed Scheme --- p.43 / Chapter 3.2.3.1 --- Overview --- p.43 / Chapter 3.2.3.2 --- Preparation of Coding --- p.44 / Chapter 3.2.3.3 --- Coding of Non-zero Coefficient Flags and EOB Decisions --- p.45 / Chapter 3.2.3.4 --- Coding of ´بLEVEL' --- p.48 / Chapter 3.2.3.5 --- Separate Coding of Color Planes --- p.53 / Chapter 3.3 --- Experimental Results --- p.54 / Chapter 3.3.1 --- Evaluation Method --- p.54 / Chapter 3.3.2 --- Methods under Evaluation --- p.55 / Chapter 3.3.3 --- Average File Size Reduction --- p.57 / Chapter 3.3.4 --- File Size Reduction on Individual Images --- p.59 / Chapter 3.3.5 --- Performance of Individual Techniques --- p.63 / Chapter 3.4 --- Discussions --- p.66 / Chapter 4. --- Video Post-processing for H.264 --- p.67 / Chapter 4.1 --- Introduction --- p.67 / Chapter 4.2 --- Proposed Method --- p.68 / Chapter 4.3 --- Experimental Results --- p.69 / Chapter 4.3.1 --- Deblocking on Compressed Frames --- p.69 / Chapter 4.3.2 --- Deblocking on Residue of Compressed Frames --- p.72 / Chapter 4.3.3 --- Performance Investigation --- p.74 / Chapter 4.3.4 --- Investigation Experiment 1 --- p.75 / Chapter 4.3.5 --- Investigation Experiment 2 --- p.77 / Chapter 4.3.6 --- Investigation Experiment 3 --- p.79 / Chapter 4.4 --- Discussions --- p.81 / Chapter 5. --- Conclusions --- p.82 / References --- p.83
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Signal compression for digital television.Truong, Huy S. January 1999 (has links)
Still image and image sequence compression plays an important role in the development of digital television. Although various still image and image sequence compression algorithms have already been developed, it is very difficult for them to achieve both compression performance and coding efficiency simultaneously due to the complexity of the compression process itself. As a results, improvements in the forms of hybrid coding, coding procedure refinement, new algorithms and even new coding concepts have been constantly tried, some offering very encouraging results.In this thesis, Block Adaptive Classified Vector Quantisation (BACVQ) has been developed as an alternative algorithm for still image compression. It is found that BACVQ achieves good compression performance and coding efficiency by combining variable block-size coding and classified VQ. Its performance is further enhanced by adopting both spatial and transform domain criteria for the image block segmentation and classification process. Alternative algorithms have also been developed to accelerate normal codebook searching operation and to determine the optimal sizes of classified VQ sub-codebooks.For image sequence compression, an adaptive spatial/temporal compression algorithm has been developed which divides an image sequence into smaller groups of pictures (GOP) using adaptive scene segmentation before BACVQ and variable block-size motion compensated predictive coding are applied to the intraframe and interframe coding processes. It is found the application of the proposed adaptive scene segmentation algorithm, an alternative motion estimation strategy and a new progressive motion estimation algorithm enables the performance and efficiency of the compression process to be improved even further.Apart from improving still image and image sequence compression algorithms, the application of parallel ++ / processing to image sequence compression is also investigated. Parallel image compression offers a more effective approach than the sequential counterparts to accelerate the compression process and bring it closer to real-time operation. In this study, a small scale parallel digital signal processing platform has been constructed for supporting parallel image sequence compression operation. It consists of a 486DX33 IBM/PC serving as a master processor and two DSP (PC-32) cards as parallel processors. Because of the independent processing and spatial arrangement natures of most image processing operations, an effective parallel image sequence compression algorithm has been developed on the proposed parallel processing platform to significantly reduce the processing time of the proposed parallel image compression algorithms.
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In Vitro Modulation of Meniscus Biosynthesis: a Basis for Understanding Cellular Response to Physiologically Relevant StimuliImler, Stacy Marie 19 July 2005 (has links)
The meniscus is a soft, fibrocartilaginous tissue critical for the maintenance of normal knee biomechanics, providing shock absorbance and overall joint lubrication and stability. The adult tissue is highly avascular with a poor autonomous repair capacity in response to injury. Despite the estimated 850,000 arthroscopic surgeries performed per year to repair torn menisci and the increasing evidence showing a high incidence of meniscal degeneration during very early stages of osteoarthritis, little is currently known of the responses of meniscal fibrochondrocytes to physiological stimuli. Therefore, this work explored the responses of meniscal fibrochondrocytes to exogenous biomechanical and biochemical stimuli in an effort to better understand the sensitivity of these cells in their native tissue matrix as well as in a 3-D scaffold environment.
Using the immature bovine model, the changes in biosynthesis of fibrochondrocytes in tissue explants and in an agarose scaffold due to unconfined oscillatory compression were explored. This biomechanical stimulus, previously identified to stimulate matrix production of chondrocytes of articular cartilage, stimulated total protein synthesis in both culture environments. In contrast, the synthesis of proteoglycans, matrix components important in mechanical stiffness and hydration of the tissue, was not affected by these compression protocols. However, the use of a biochemical stimulus in the form of anabolic cytokines significantly enhanced both protein and proteoglycan synthesis as a function of culture environment as well as type of cytokine used. The superposition of oscillatory compression in addition to the use of these potent biochemical stimulators, insulin-like growth factor-I or transforming growth factor-beta 1, did not further enhance matrix synthesis of fibrochondrocytes in agarose culture, suggesting an insensitivity of the fibrochondrocytes to biomechanical stimuli during early stages of matrix maturation within the agarose scaffold. As a combination of biomechanical and biochemical stimuli are responsible for directing the development, maintenance, and repair of the tissue, these findings aid in understanding fibrocartilage maintenance through studying responses in a tissue explant model. Additionally, studying agarose scaffolds aid in the understanding fibrocartilage development and deposition of a de novo matrix.
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The Research of Schedule Compression Methods In Software DevelopmentCho, Chia-Hung 06 July 2005 (has links)
Software projects face a common problem that time is always not enough, and only a few projects can be finished on schedule and within budget. Projects often need to accelerate the progress to compensate the laggard portion, or to compress schedule to accommodate to the market competition.
Opposite to the generality of the problem, researchers didn¡¦t focus on this field, and the quantitative studies had low degree of explanation. To study the issue, this thesis used the qualitative case study to interview four development teams. It is to understand how the compression methods of the teams work, and induce to three dimensions, including management, development process, and team structure. These teams have fundamentally different characters in order to find the most representative cases in limited samples.
Finally, this thesis comprehends how the compression methods work, and how the teams use compression methods under which project characters. In addition to comparing the results with prior literature, new compression methods are also discovered. The final results of this research could serve as guidelines to the development teams that face the problem of schedule compression.
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Schedule Compression Methods for Software Developmenthsu, shih-pei 10 June 2001 (has links)
none
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Video compression and rate control methods based on the wavelet transformBalster, Eric J., January 2004 (has links)
Thesis (Ph. D.)--Ohio State University, 2003. / Title from first page of PDF file. Document formatted into pages; contains xxv, 142 p.; also includes graphics. Includes abstract and vita. Advisor: Yuan F. Zheng, Dept. of Electrical and Computer Engineering. Includes bibliographical references (p. 135-142).
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Real-time video postprocessing algorithms and metrics /Gao, Wenfeng, January 2003 (has links)
Thesis (Ph. D.)--University of Washington, 2003. / Vita. Includes bibliographical references (leaves 94-103).
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Rate scalable foveated image and video communications /Wang, Zhou, January 2001 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references (leaves 155-176). Available also in a digital version from Dissertation Abstracts.
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