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Academic literature on the topic 'Compression scheme'

Author: Grafiati

Published: 25 May 2024

Last updated: 22 June 2025

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Journal articles on the topic "Compression scheme"

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Jha, Mithilesh Kumar, Brejesh Lall, and Sumantra Dutta Roy. "Statistically Matched Wavelet Based Texture Synthesis in a Compressive Sensing Framework." ISRN Signal Processing 2014 (February 17, 2014): 1–18. http://dx.doi.org/10.1155/2014/838315.

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This paper proposes a statistically matched wavelet based textured image coding scheme for efficient representation of texture data in a compressive sensing (CS) frame work. Statistically matched wavelet based data representation causes most of the captured energy to be concentrated in the approximation subspace, while very little information remains in the detail subspace. We encode not the full-resolution statistically matched wavelet subband coefficients but only the approximation subband coefficients (LL) using standard image compression scheme like JPEG2000. The detail subband coefficients, that is, HL, LH, and HH, are jointly encoded in a compressive sensing framework. Compressive sensing technique has proved that it is possible to achieve a sampling rate lower than the Nyquist rate with acceptable reconstruction quality. The experimental results demonstrate that the proposed scheme can provide better PSNR and MOS with a similar compression ratio than the conventional DWT-based image compression schemes in a CS framework and other wavelet based texture synthesis schemes like HMT-3S.

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Gao, Jian Qiang, Shao Dong Sun, Li Kun Wang, and Ning Wang. "The Analysis on the Scheme of the Flue Gas Compressor of a 300 MW Oxy-Fuel Pulverized Coal Fired Boiler." Applied Mechanics and Materials 602-605 (August 2014): 638–41. http://dx.doi.org/10.4028/www.scientific.net/amm.602-605.638.

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The compression of the flue gas is one of the most critical processes of CO2 recycling in oxy-fuel combustion technology. With a 300 MW Oxy-fuel pulverized coal fired boiler taken as an example of study, the selection of compressors of its flue gas compressing system is analyzed by the thermodynamic calculation. In this paper, two centrifugal compressors with the same specification are in parallel running as Scheme 1 of selection, while an axial compressor and a piston compressor are in series operation as Scheme 2 of selection. It shows that the Scheme 2 has the advantage of the energy consumption and water separation of the flue gas in inter-cooler comparing with Scheme1.

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Waleed, Muhammad, Tai-Won Um, Aftab Khan, and Ali Khan. "On the Utilization of Reversible Colour Transforms for Lossless 2-D Data Compression." Applied Sciences 10, no. 3 (2020): 937. http://dx.doi.org/10.3390/app10030937.

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Reversible Colour Transforms (RCTs) in conjunction with Bi-level Burrows–Wheeler Compression Algorithm (BBWCA) allows for high-level lossless image compression as demonstrated in this study. The RCTs transformation results in exceedingly coordinated image information among the neighbouring pixels as compared to the RGB colour space. This aids the Burrows–Wheeler Transform (BWT) based compression scheme and achieves compression ratios of high degree at the subsequent steps of the program. Validation has been done by comparing the proposed scheme across a range of benchmarks schemes and the performance of the proposed scheme is above par the other schemes. The proposed compression outperforms the techniques exclusively developed for 2-D electrocardiogram (EEG), RASTER map and Color Filter Array (CFA) image compression. The proposed system shows no dependency over parameters like image size, its type or the medium in which it is captured. A comprehensive analysis of the proposed scheme concludes that it achieves a significant increase in compression and depicts comparable complexity similar to the various benchmark schemes.

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Armenta Ramade, Álvaro, and Arturo Serrano Santoyo. "802.11g multilayer header compression for VoIP in remote rural contexts." Revista Facultad de Ingeniería Universidad de Antioquia, no. 71 (March 4, 2014): 101–14. http://dx.doi.org/10.17533/udea.redin.15011.

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This article presents a Multilayer Header Compression scheme for VoIP packets in 802.11 wireless networks that does not require context synchronization of compressor and decompressor units. The reduction of the header size is accomplished through the static field compression of the RTP/UDP/IP headers in conjunction with an 8 bit virtual addressing in the 802.11 MAC layer. Considering the RTP/UDP/IP/MAC header fields, this scheme allows 48% header compression efficiency compared with 41% provided by the CRTP and RoHC schemes. Given that our proposal does not require context synchronization, the decompressor will regenerate the headers even in high packet loss rate conditions.

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Xu, Haoran, Petr M. Anisimov, Bruce E. Carlsten, Leanne D. Duffy, Quinn R. Marksteiner, and River R. Robles. "X-ray Free Electron Laser Accelerator Lattice Design Using Laser-Assisted Bunch Compression." Applied Sciences 13, no. 4 (2023): 2285. http://dx.doi.org/10.3390/app13042285.

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We report the start-to-end modeling of our accelerator lattice design employing a laser-assisted bunch compression (LABC) scheme in an X-ray free electron laser (XFEL), using the proposed Matter-Radiation Interactions in Extremes (MaRIE) XFEL parameters. The accelerator lattice utilized a two-stage bunch compression scheme, with the first bunch compressor performing a conventional bulk compression enhancing the beam current from 20 A to 500 A, at 750 MeV. The second bunch compression was achieved by modulating the beam immediately downstream of the first bunch compressor by a laser with 1-μm wavelength in a laser modulator, accelerating the beam to the final energy of 12 GeV, and compressing the individual 1-μm periods of the modulated beam into a sequence of microbunches with 3-kA current spikes by the second bunch compressor. The LABC architecture presented had been developed based on the scheme of enhanced self-amplified spontaneous emission (ESASE), but operated in a disparate regime of parameters. Enabled by the novel technology of the cryogenic normal conducting radiofrequency photoinjector, we investigated an electron beam with ultra-low emittance at the starting point of the lattice design. Our work aimed at mitigating the well-known beam instabilities to preserve the beam emittance and suppress the energy spread growth.

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Lu, Tzu-Chuen, and Chin-Chen Chang. "Data Compressor for VQ Index Tables." Fundamenta Informaticae 65, no. 4 (2005): 353–71. https://doi.org/10.3233/fun-2005-65404.

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The vector quantization (VQ) compression scheme has been well accepted as an efficient image compression technique. However, the compression bit rate of the VQ scheme is limited. In order to improve its efficiency, in this paper, we shall propose a new lossless data compression scheme to further condense the VQ index table. The proposed scheme exploits the inter-block correlations in the index table to re-encode the indices. Unlike the well known existing re-encoding schemes such as SOC and STC, the proposed scheme uses a smaller number of compression codes to encode every index that coincides with another on the predefined path. Compared with VQ, SOC and STC, the proposed scheme performs better in terms of compression bit rate.

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Moreno-Alvarado, Rodolfo, Eduardo Rivera-Jaramillo, Mariko Nakano, and Hector Perez-Meana. "Simultaneous Audio Encryption and Compression Using Compressive Sensing Techniques." Electronics 9, no. 5 (2020): 863. http://dx.doi.org/10.3390/electronics9050863.

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The development of coding schemes with the capacity to simultaneously encrypt and compress audio signals is a subject of active research because of the increasing necessity for transmitting sensitive audio information over insecure communication channels. Thus, several schemes have been developed; firstly, some of them compress the digital information and subsequently encrypt the resulting information. These schemas efficiently compress and encrypt the information. However, they may compromise the information as it can be accessed before encryption. To overcome this problem, a compressing sensing-based system to simultaneously compress and encrypt audio signals is proposed in which the audio signal is segmented in frames of 1024 samples and transformed into a sparse frame using the discrete cosine transform (DCT). Each frame is then multiplied by a different sensing matrix generated using the chaotic mixing scheme. This fact allows that the proposed scheme satisfies the extended Wyner secrecy (EWS) criterion. The evaluation results obtained using several genres of audio signals show that the proposed system allows to simultaneously compress and encrypt audio signals, satisfying the EWS criterion.

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Wang, Zi Long, Tu Ji, Mei Song Zheng, Jun Ye Wang, and Li Jian Li. "An Efficient Two-Dimension BIST Compression Approach." Applied Mechanics and Materials 713-715 (January 2015): 552–57. http://dx.doi.org/10.4028/www.scientific.net/amm.713-715.552.

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In this paper a two-dimension BIST compression scheme is presented; the proposed scheme is utilized in order to drive down the number of deterministic vectors to achieve complete fault coverage in BIST applications. By introducing shifting compression and input reduction, vertical and horizontal compression are realized respectively to achieve two-dimension BIST compression. Experimental results show that the BIST shifting compression based on input reduction can achieve great compression rate as much as 99%. Comparisons with previously competitive presented schemes indicate that the proposed scheme provide an efficient BIST compression approach with lower storage overhead.

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Chen, Yang, and Zheng Qin. "Region-Based Image-Fusion Framework for Compressive Imaging." Journal of Applied Mathematics 2014 (2014): 1–9. http://dx.doi.org/10.1155/2014/219540.

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A novel region-based image-fusion framework for compressive imaging (CI) and its implementation scheme are proposed. Unlike previous works on conventional image fusion, we consider both compression capability on sensor side and intelligent understanding of the image contents in the image fusion. Firstly, the compressed sensing theory and normalized cut theory are introduced. Then region-based image-fusion framework for compressive imaging is proposed and its corresponding fusion scheme is constructed. Experiment results demonstrate that the proposed scheme delivers superior performance over traditional compressive image-fusion schemes in terms of both object metrics and visual quality.

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AKSENOV, A. A., A. A. AKSENOV, and O. D. DYACHKIN. "COMPRESSING SHORT STRINGS WITH A LIMITED OUTPUT ALPHABET." Vestnik LSTU, no. 4 (2023): 5–8. http://dx.doi.org/10.53015/23049235_2023_4_5.

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The paper analyses the possibility and impact of limiting the output alphabet when compressing short strings using the novel FSST [1] compression scheme. It was established that if a small number of bytes are excluded from the alphabet (6 out of 256 possible, with 250 bytes left in the alphabet), it barely impacts the average string compression ratio while simplifying FSST scheme implementation in production systems. Moreover, it was established that even with significant restrictions (with only 92 Latin-1 bytes out of 256 possible), the FSST scheme is still applicable. The paper also outlines further research directions concerning the improvement of the compression ratio via the FSST compression scheme.

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Dissertations / Theses on the topic "Compression scheme"

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Lim, Seng. "Image compression scheme for network transmission." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1995. http://handle.dtic.mil/100.2/ADA294959.

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Presvôts, Corentin. "Multiple-Model Coding Scheme for Electrical Signal Compression." Electronic Thesis or Diss., université Paris-Saclay, 2025. http://www.theses.fr/2025UPASG007.

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L'intégration des sources d'énergie renouvelables dans le réseau électrique introduit une dynamique plus complexe, nécessitant un contrôle plus efficace et à faible latence. Ce contrôle exige la transmission de gros volumes de données des sous-stations aux centres de contrôle supérieurs. Pour répondre aux contraintes de débit du réseau, il est crucial de développer des techniques de compression efficaces, adaptées aux caractéristiques spécifiques des signaux électriques. Actuellement, les Phasor Measurement Units (PMUs) sont les dispositifs les plus couramment utilisés pour acquérir et compresser ces signaux. Cependant, les PMUs ne peuvent pas représenter avec précision les transitoires rapides. Dans la première partie de cette thèse, une méthode de compression utilisant des réseaux de neurones, basée sur des Auto-encodeurs variationnels (VAEs), est décrite. Cette méthode, initialement développée pour la compression d'images, est adaptée dans cette thèse à la compression des échantillons de signaux électriques. Le principe repose sur l'optimisation de l'étape de transformation en minimisant un compromis débit-distorsion sur un ensemble de signaux électriques d'entraînement. Cette méthode permet d'optimiser l'ensemble de la chaîne de compression en tenant compte de la quantification et du codage entropique, offrant ainsi de meilleures performances en moyenne que les méthodes classiques non entraînables, utilisant par exemple une transformée en cosinus discrètes (DCT) ou une transformée en ondelettes discrètes (DWT).La seconde partie décrit un schéma de codage multi-modèles (MMC) proposé pour la compression des échantillons de signaux électriques. Pour réduire la latence, l'approche MMC opère sur des fenêtres d'environ une période électrique (de l'ordre de la latence des PMUs), contenant donc un nombre limité d'échantillons. Dans un premier étage de compression, plusieurs modèles paramétriques de signaux sont comparés (modèles sinusoïdaux, polynomiaux ou encore prédictifs) pour obtenir une représentation grossière du signal électrique. Dans un deuxième étage, plusieurs techniques de codage par transformation sont utilisées pour compresser le résidu de reconstruction du premier étage. Les transformations utilisées sont, la DCT, la DWT et les VAEs mentionnés précédemment. Les paramètres du modèle sont quantifiés et l'allocation du budget de débit entre les deux étages est optimisée en fonction d'un débit cible. Néanmoins, imposer une contrainte de budget entraîne des variations dans la qualité de reconstruction des signaux échantillonnés, ce qui peut ne pas répondre aux exigences strictes de qualité de reconstruction imposées par les utilisateurs finaux.Une troisième partie vise donc à déterminer le budget de bits minimum nécessaire pour respecter une contrainte de distorsion maximale imposée. Le degré de liberté supplémentaire, offert par le choix du budget total, augmente la complexité de l'approche MMC par rapport à sa variante à débit fixe et peut être incompatible avec les contraintes de temps réel. Deux méthodes distinctes sont proposées pour la sélection du modèle et l'allocation des bits entre les deux étages. La première méthode repose sur une recherche exhaustive pour déterminer le nombre de bits à allouer aux deux étages de compression. La seconde méthode utilise une recherche par section dorée. Le coût de calcul de ces deux approches est encore réduit en amont grâce à une estimation préalable du meilleur modèle et de l'allocation optimale du budget de bits entre les deux étages, de manière à satisfaire la contrainte de distorsion. Cette estimation s'appuie sur des modèles débit-distorsion<br>The integration of renewable energy sources into the electrical grid introduces more complex dynamics, requiring more efficient and low-latency control. This control demands the transmission of large volumes of data from substations to higher-level control centers. To address network bandwidth constraints, it is essential to develop efficient compression techniques tailored to the specific characteristics of electrical signals. Currently, Phasor Measurement Units (PMUs) are the most commonly used devices for acquiring and compressing these signals. However, PMU cannot accurately represent fast transients. In the first part of this thesis, a compression method using neural networks, based on Variational Autoencoders (VAEs), is described. Initially developed for image compression, this method is adapted in this work to the compression of sampled electrical signals. The principle relies on optimizing the transformation step by minimizing a Rate-Distortion (RD) trade-off over a training set of electrical signals. This method enables the optimization of the entire compression pipeline by accounting for quantization and entropy coding, thus providing better average performance compared to classical non-trainable methods, such as the Discrete Cosine Transform (DCT) or the discrete wavelet transform Discrete Wavelet Transform (DWT). The second part describes a proposed multi-model coding scheme for the compression of sampled electrical signals. To reduce latency, the Multiple Model Compression (MMC) approach operates on windows of approximately one electrical period (on the order of glspl{pmu} latency), thus containing a limited number of samples. In the first compression stage, several parametric signal models (sinusoidal, polynomial, and predictive models) are compared to obtain a coarse representation of the electrical signal. In the second stage, several transform coding techniques are used to compress the reconstruction residual from the first stage. The transformations used include the DCT, DWT, and the previously mentioned VAEs. The model parameters are quantized, and the bit budget allocation between the two stages is optimized based on a target rate. However, imposing a rate constraint introduces variations in the reconstruction quality of the sampled signals, which may not meet the strict quality requirements imposed by end users. The third part of this thesis aims to determine the minimum bit budget required to satisfy a maximum distortion constraint. The additional degree of freedom provided by the choice of the total bit budget increases the complexity of the MMC approach compared to its fixed-rate variant and may be incompatible with real-time constraints. Two distinct methods are proposed for model selection and bit allocation between the two stages. The first method relies on an exhaustive search to determine the number of bits to allocate to both compression stages. The second method uses a golden-section search. The computational cost of these two approaches is further reduced by a preliminary estimation of the best model and the optimal bit allocation between the two stages to meet the distortion constraint. This estimation is based on RD models

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Li, Yun, Mårten Sjöström, Ulf Jennehag, Roger Olsson, and Tourancheau Sylvain. "Subjective Evaluation of an Edge-based Depth Image Compression Scheme." Mittuniversitetet, Avdelningen för informations- och kommunikationssystem, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-18539.

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Multi-view three-dimensional television requires many views, which may be synthesized from two-dimensional images with accompanying pixel-wise depth information. This depth image, which typically consists of smooth areas and sharp transitions at object borders, must be consistent with the acquired scene in order for synthesized views to be of good quality. We have previously proposed a depth image coding scheme that preserves significant edges and encodes smooth areas between these. An objective evaluation considering the structural similarity (SSIM) index for synthesized views demonstrated an advantage to the proposed scheme over the High Efficiency Video Coding (HEVC) intra mode in certain cases. However, there were some discrepancies between the outcomes from the objective evaluation and from our visual inspection, which motivated this study of subjective tests. The test was conducted according to ITU-R BT.500-13 recommendation with Stimulus-comparison methods. The results from the subjective test showed that the proposed scheme performs slightly better than HEVC with statistical significance at majority of the tested bit rates for the given contents.

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Mensmann, Jörg, Timo Ropinski, and Klaus Hinrichs. "A GPU-Supported Lossless Compression Scheme for Rendering Time-Varying Volume Data." University of Münster, Germany, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-92867.

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Since the size of time-varying volumetric data sets typically exceeds the amount of available GPU and main memory, out-of-core streaming techniques are required to support interactive rendering. To deal with the performance bottlenecks of hard-disk transfer rate and graphics bus bandwidth, we present a hybrid CPU/GPU scheme for lossless compression and data streaming that combines a temporal prediction model, which allows to exploit coherence between time steps, and variable-length coding with a fast block compression algorithm. This combination becomes possible by exploiting the CUDA computing architecture for unpacking and assembling data packets on the GPU. The system allows near-interactive performance even for rendering large real-world data sets with a low signal-to-noise-ratio, while not degrading image quality. It uses standard volume raycasting and can be easily combined with existing acceleration methods and advanced visualization techniques.

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Bernat, Andrew. "Which partition scheme for what image?, partitioned iterated function systems for fractal image compression." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2002. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ65602.pdf.

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Kadri, Imen. "Controlled estimation algorithms of disparity map using a compensation compression scheme for stereoscopic image coding." Thesis, Paris 13, 2020. http://www.theses.fr/2020PA131002.

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Ces dernières années ont vu apparaître de nombreuses applications utilisant la technologie 3D tels que les écrans de télévisions 3D, les écrans auto-stéréoscopiques ou encore la visio-conférence stéréoscopique. Cependant ces applications nécessitent des techniques bien adaptées pour comprimer efficacement le volume important de données à transmettre ou à stocker. Les travaux développés dans cette thèse concernent le codage d’images stéréoscopiques et s’intéressent en particulier à l'amélioration de l'estimation de la carte de disparité dans un schéma de Compression avec Compensation de Disparité (CCD). Habituellement, l'algorithme d’appariement de blocs similaires dans les deux vues permet d’estimer la carte de disparité en cherchant à minimiser l’erreur quadratique moyenne entre la vue originale et sa version reconstruite sans compensation de disparité. L’erreur de reconstruction est ensuite codée puis décodée afin d’affiner (compenser) la vue prédite. Pour améliorer la qualité de la vue reconstruite, dans un schéma de codage par CCD, nous avons prouvé que le concept de sélectionner la disparité en fonction de l'image compensée plutôt que de l'image prédite donne de meilleurs résultats. En effet, les simulations montrent que notre algorithme non seulement réduit la redondance inter-vue mais également améliore la qualité de la vue reconstruite et compensée par rapport à la méthode habituelle de codage avec compensation de disparité. Cependant, cet algorithme de codage requiert une grande complexité de calculs. Pour remédier à ce problème, une modélisation simplifiée de la manière dont le codeur JPEG (à savoir la quantification des composantes DCT) impacte la qualité de l’information codée est proposée. En effet, cette modélisation a permis non seulement de réduire la complexité de calculs mais également d’améliorer la qualité de l’image stéréoscopique décodée dans un contexte CCD. Dans la dernière partie, une métrique minimisant conjointement la distorsion et le débit binaire est proposée pour estimer la carte de disparité en combinant deux algorithmes de codage d’images stéréoscopiques dans un schéma CCD<br>Nowadays, 3D technology is of ever growing demand because stereoscopic imagingcreate an immersion sensation. However, the price of this realistic representation is thedoubling of information needed for storage or transmission purpose compared to 2Dimage because a stereoscopic pair results from the generation of two views of the samescene. This thesis focused on stereoscopic image coding and in particular improving thedisparity map estimation when using the Disparity Compensated Compression (DCC)scheme.Classically, when using Block Matching algorithm with the DCC, a disparity mapis estimated between the left image and the right one. A predicted image is thencomputed.The difference between the original right view and its prediction is called theresidual error. This latter, after encoding and decoding, is injected to reconstruct theright view by compensation (i.e. refinement) . Our first developed algorithm takes intoaccount this refinement to estimate the disparity map. This gives a proof of conceptshowing that selecting disparity according to the compensated image instead of thepredicted one is more efficient. But this done at the expense of an increased numericalcomplexity. To deal with this shortcoming, a simplified modelling of how the JPEGcoder, exploiting the quantization of the DCT components, used for the residual erroryields with the compensation is proposed. In the last part, to select the disparity mapminimizing a joint bitrate-distortion metric is proposed. It is based on the bitrateneeded for encoding the disparity map and the distortion of the predicted view.This isby combining two existing stereoscopic image coding algorithms

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Philibert, Manon. "Cubes partiels : complétion, compression, plongement." Electronic Thesis or Diss., Aix-Marseille, 2021. http://www.theses.fr/2021AIXM0403.

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Les sous-graphes isométriques d'hypercubes (dit cubes partiels) constituent une classe centrale de la théorie métrique des graphes. Ils englobent des familles de graphes importantes (arbres, graphes médians, etc.), provenant de différents domaines de recherche, tels que la géométrie discrète, la combinatoire ou la théorie géométrique des groupes. Nous étudions tout d'abord la structure des cubes partiels de VC-dimension 2. Nous montrons que ces graphes peuvent être obtenus par amalgamations à partir de deux types de cellules combinatoires.Cette décomposition nous permet d’obtenir diverses caractérisations. En particulier, tout cube partiel de VC-dimension 2 peut être complété en cube partiel ample de VC-dimension 2. Nous montrons ensuite que les graphes de topes des matroïdes orientés et des complexes de matroïdes orientés uniformes peuvent aussi être complétés en cubes partiels amples de même VC-dimension.En utilisant un résultat de Moran et Warmuth, nous établissons que ces classes vérifient la conjecture de Floyd et Warmuth, l'une des plus vielles conjectures en théorie de l'apprentissage. C'est-à-dire qu'elles admettent des schémas de compression (étiquetés non propres) de taille leur VC-dimension.Par la suite, nous décrivons un schéma de compression étiqueté propre de taille d pour les complexes de matroïdes orientés de VC-dimension d, généralisant ainsi le résultat de Moran et Warmuth pour les amples. Enfin, nous fournissons une caractérisation par pc-mineurs exclus et parsous-graphes isométriques interdits des cubes partiels plongeables isométriquement dans la grille Z^2 et dans le cylindre P_n \square C_{2k} pour un certain n et k > 4<br>Partial cubes (aka isometric subgraphs of hypercubes) are a fundamental class of metric graph theory. They comprise many important graph classes (trees, median graphs, tope graphs of complexes of oriented matroids, etc.), arising from different areas of research such as discrete geometry, combinatorics or geometric group theory.First, we investigate the structure of partial cubes of VC-dimension 2. We show that those graphs can be obtained via amalgams from even cycles and full subdivisions of complete graphs. This decomposition allows us to obtain various characterizations. In particular, any partial cube can be completed to an ample partial cube of VC-dimension 2. Then, we show that the tope graphs of oriented matroids and complexes of uniform oriented matroids can also be completed to ample partial cubes of the same VC-dimension.Using a result of Moran and Warmuth, we establish that those classes satisfy the conjecture of Floyd and Warmuth, one of the oldest open problems in computational machine learning. Particularly, they admit (improper labeled) compression schemes of size their VC-dimension.Next, we describe a proper labeled compression scheme of size d for complexes of oriented matroids of VC-dimension d, generalizing the result of Moran and Warmuth for ample sets. Finally, we give a characterization via excluded pc-minors and via forbidden isometric subgraphs of partial cubes isometrically embedded into the grid \mathbb{Z}^2 and the cylinder P_n \square C_{2k} for some n and k > 4

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Samuel, Sindhu. "Digital rights management (DRM) : watermark encoding scheme for JPEG images." Pretoria : [s.n.], 2007. http://upetd.up.ac.za/thesis/available/etd-09122008-182920/.

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Bekkouche, Hocine. "Synthèse de bancs de filtres adaptés, application à la compression des images." Phd thesis, Université Paris Sud - Paris XI, 2007. http://tel.archives-ouvertes.fr/tel-00345288.

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Les travaux développés dans cette thèse portent sur les décompositions multirésolution dans un cadre de lifting scheme, appliquées à la compression d'images. Pour commencer, une structure de décomposition consistant en un “lifting scheme généralisé” est proposée. Ce schéma permet d'exploiter toute l'information disponible au décodage dans l'étape de prédiction. Cela est rendu possible par l'ajout d'un filtre de prédiction supplémentaire par rapport à la structure classique de lifting scheme. Le schéma proposé est ensuite associé à deux méthodes d'adaptation. La première, appelée GAE, suppose une stationnarité globale de l'image, tandis que la seconde, LAE ne suppose qu'une stationnarité locale de l'image. Dans ce dernier cas, les filtres prédicteurs sont adaptatifs. Trois applications de ces méthodes en compression d'images sont ensuite proposées. Dans un premier temps, une comparaison des performances en compression sans perte sur des images de textures, synthétiques, gaussiennes, à stationnarités locale et globale (vérifiant les hypothèses plus haut), est réalisée. Sur ces signaux, les mesures d'entropie d'ordre 1 ont montré que les méthodes proposées offrent en moyenne un gain en codage de 0,5 bpp (GAE) et 0,8 bpp (LAE) par rapport à la décomposition en ondelette (9,7), de 0,8 bpp (GAE) et 1,11 bpp (LAE) par rapport à la (5,3) et de 0,41 bpp (GAE) et 0,65 bpp (LAE) par rapport à la méthode de Gerek et Çetin. La deuxième application concerne le codage sans perte d'images réelles de natures variées. Les gains par rapport à l'état de l'art se sont révélés plus faibles que ceux obtenus pour les images synthétiques. Enfin, la dernière application traite les cas du codage progressif et du codage avec perte. Pour la compression avec pertes, nous avons modifié la méthode LAE pour palier aux problèmes de divergence dus à l'impossibilité au niveau du décodeur de reconstruire les filtres prédicteurs à partir d'échantillons quantifiés. Elle se révèle plus efficace que lorsque l'on utilise les filtres usuels de longueur fixe (9,7) et (5,3).

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Ali, Azad [Verfasser], Neeraj [Akademischer Betreuer] Suri, Christian [Akademischer Betreuer] Becker, Stefan [Akademischer Betreuer] Katzenbeisser, Andy [Akademischer Betreuer] Schürr, and Marc [Akademischer Betreuer] Fischlin. "Fault-Tolerant Spatio-Temporal Compression Scheme for Wireless Sensor Networks / Azad Ali ; Neeraj Suri, Christian Becker, Stefan Katzenbeisser, Andy Schürr, Marc Fischlin." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2017. http://d-nb.info/1127225405/34.

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Books on the topic "Compression scheme"

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Charles, Fenimore, and National Institute of Standards and Technology (U.S.), eds. Characterization of projection systems for the MPEG-4 digital cinema compression scheme evaluation. U.S. Dept. of Commerce, Technology Administration, National Institute of Standards and Technology, 2001.

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Charles, Fenimore, and National Institute of Standards and Technology (U.S.), eds. Characterization of projection systems for the MPEG-4 digital cinema compression scheme evaluation. U.S. Dept. of Commerce, Technology Administration, National Institute of Standards and Technology, 2001.

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Charles, Fenimore, and National Institute of Standards and Technology (U.S.), eds. Characterization of projection systems for the MPEG-4 digital cinema compression scheme evaluation. U.S. Dept. of Commerce, Technology Administration, National Institute of Standards and Technology, 2001.

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Charles, Fenimore, and National Institute of Standards and Technology (U.S.), eds. Characterization of projection systems for the MPEG-4 digital cinema compression scheme evaluation. U.S. Dept. of Commerce, Technology Administration, National Institute of Standards and Technology, 2001.

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Ravindra Babu, T., M. Narasimha Murty, and S. V. Subrahmanya. Compression Schemes for Mining Large Datasets. Springer London, 2013. http://dx.doi.org/10.1007/978-1-4471-5607-9.

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Tudor, P. N. Digital video compression: Standardisation of scalable coding schemes. British Broadcasting Corporation. Research and Development Department, 1994.

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Aburas, Abdul Razag Ali. Data compression schemes for pattern recognition in digital images using fractals. De Montfort University, 1997.

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United States. National Aeronautics and Space Administration., ed. An artificial compression method for ENO schemes: The slope modification method. Dept. fo Mathematics, UCLA, 1988.

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Aburas, Abdul Razag Ali. Data compression schemes for pattern recognition in digital images using fractals. SERCentre, De Montfort University, 1997.

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Currie, Daniel L. Implementation and efficiency of steganographic techniques in bitmapped images and embedded data survivability against lossy compression schemes. Naval Postgraduate School, 1996.

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Book chapters on the topic "Compression scheme"

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Ravindra Babu, T., M. Narasimha Murty, and S. V. Subrahmanya. "Run-Length-Encoded Compression Scheme." In Compression Schemes for Mining Large Datasets. Springer London, 2013. http://dx.doi.org/10.1007/978-1-4471-5607-9_3.

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Schuster, Guido M., and Aggelos K. Katsaggelos. "An Optimal Polygonal Boundary Encoding Scheme." In Rate-Distortion Based Video Compression. Springer US, 1997. http://dx.doi.org/10.1007/978-1-4757-2566-7_8.

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Gupta, Rupesh, and Santanu Chaudhury. "A Scheme for Attentional Video Compression." In Lecture Notes in Computer Science. Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-21786-9_74.

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El-Qawasmeh, Eyas, Ahmed Mansour, and Mohammad Al-Towiq. "Development of a New Compression Scheme." In Networked Digital Technologies. Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-14292-5_9.

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Chaabane, Wafa, Régis Fournier, Amine Naït-ali, et al. "Supervised Biometric System Using Multimodal Compression Scheme." In Progress in Pattern Recognition, Image Analysis, Computer Vision, and Applications. Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-33275-3_47.

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Vivek, Srinivas. "Revisiting a Masked Lookup-Table Compression Scheme." In Lecture Notes in Computer Science. Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-71667-1_19.

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Kim, Mi-Ae, Kil-Sang Yoo, and Won-Hyung Lee. "Fragile Watermarking Scheme for Accepting Image Compression." In Embedded and Ubiquitous Computing – EUC 2005. Springer Berlin Heidelberg, 2005. http://dx.doi.org/10.1007/11596356_93.

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Pinter, Shlomit S., and Israel Waldman. "Selective Code Compression Scheme for Embedded Systems." In Lecture Notes in Computer Science. Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-71528-3_19.

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Itokawa, Yuko, Koichiro Katoh, Tomoyuki Uchida, and Takayoshi Shoudai. "Algorithm Using Expanded LZ Compression Scheme for Compressing Tree Structured Data." In Lecture Notes in Electrical Engineering. Springer Netherlands, 2009. http://dx.doi.org/10.1007/978-90-481-3517-2_26.

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Lamparter, Bernd, and Wolfgang Effelsberg. "eXtended color cell compression — A runtime-efficient compression scheme for software video." In Lecture Notes in Computer Science. Springer Berlin Heidelberg, 1994. http://dx.doi.org/10.1007/3-540-58494-3_16.

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Conference papers on the topic "Compression scheme"

1

Xue, Xianglian, Haiyan Jin, and Changjun Zhou. "Adaptive Compression-Encryption Scheme for Medical Image Based on Improved Compressive Sensing and Deoxyribonucleic Acid Coding-Compression." In 2024 IEEE International Conference on Bioinformatics and Biomedicine (BIBM). IEEE, 2024. https://doi.org/10.1109/bibm62325.2024.10822367.

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Wu, Meng, Huanbang Chen, Fuzheng Yang, Haitao Yang, and Junkai Feng. "A Reference Frame Compression Scheme via AVS Perceptual Lossless Compression in Video Coding." In 2024 International Conference on Ubiquitous Communication (Ucom). IEEE, 2024. http://dx.doi.org/10.1109/ucom62433.2024.10695844.

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Liang, Junhui, Yamei Chen, Hongkui Wang, Hailang Yang, and Li Yu. "Secondary Intra Prediction Scheme for HEVC." In 2020 Data Compression Conference (DCC). IEEE, 2020. http://dx.doi.org/10.1109/dcc47342.2020.00068.

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Khalifeh, Ala', and Homayoun Yousefi'zadeh. "A Hybrid Media Transmission Scheme for Wireless VoIP." In 2010 Data Compression Conference. IEEE, 2010. http://dx.doi.org/10.1109/dcc.2010.48.

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Wiseman, Yair. "Compression scheme for RFID equipment." In 2016 IEEE International Conference on Electro Information Technology (EIT). IEEE, 2016. http://dx.doi.org/10.1109/eit.2016.7535270.

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Ding, Yi, Olivier Baudin, Patricia V. Beretta, and Remy Prost. "Medically adapted JPEG compression scheme." In Medical Imaging 1995, edited by Yongmin Kim. SPIE, 1995. http://dx.doi.org/10.1117/12.207648.

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Bhaumik, B., G. S. Visweswaran, and R. Lakshminarasimhan. "A new test compression scheme." In Proceedings Twelfth International Conference on VLSI Design. (Cat. No.PR00013). IEEE, 1999. http://dx.doi.org/10.1109/icvd.1999.745131.

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Hanus, Pavol, Janis Dingel, Georg Chalkidis, and Joachim Hagenauer. "Source Coding Scheme for Multiple Sequence Alignments." In 2009 Data Compression Conference (DCC). IEEE, 2009. http://dx.doi.org/10.1109/dcc.2009.64.

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Puchala, Dariusz, Kamil Stokfiszewski, and Mykhaylo Yatsymirskyy. "Encryption Before Compression Coding Scheme for JPEG Image Compression Standard." In 2020 Data Compression Conference (DCC). IEEE, 2020. http://dx.doi.org/10.1109/dcc47342.2020.00039.

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Abedini, Navid, Sunil P. Khatri, and Serap A. Savari. "A SAT-Based Scheme to Determine Optimal Fix-Free Codes." In 2010 Data Compression Conference. IEEE, 2010. http://dx.doi.org/10.1109/dcc.2010.22.

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Reports on the topic "Compression scheme"

1

Wu, Kesheng, Ekow J. Otoo, and Arie Shoshani. An efficient compression scheme for bitmap indices. Office of Scientific and Technical Information (OSTI), 2004. http://dx.doi.org/10.2172/841308.

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Kidner, R. E. Real-time data compression using a fixed Huffman encoding scheme. Office of Scientific and Technical Information (OSTI), 1995. http://dx.doi.org/10.2172/29404.

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Boynton, P. A., and C. Fenimore. Characterization of projection systems for the MPEG-4 digital cinema compression scheme evaluation. National Institute of Standards and Technology, 2001. http://dx.doi.org/10.6028/nist.ir.6792.

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Sun, Yipeng. Preliminary Study on Two Possible Bunch Compression Schemes at NLCTA. Office of Scientific and Technical Information (OSTI), 2011. http://dx.doi.org/10.2172/1024170.

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Murray, Trevor, and Timothy Jacobs. PR-457-16200-R01 Control of Vented Methane Emissions from Integral Compressor Engines. Pipeline Research Council International, Inc. (PRCI), 2018. http://dx.doi.org/10.55274/r0011475.

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At natural gas pipeline compressor stations, methane emissions from compressor and engine crankcases are often vented directly into the atmosphere. There may be advantages to capturing these emissions and using them to offset fuel usage and / or decrease the overall carbon footprint of such a typical compressor station. This study evaluates the feasibility of directing such captured emissions into the intake of the compressor engine and subsequently combusting the methane emissions into carbon dioxide and water. Although seemingly an obvious or trivial solution, there are in fact several challenges and issues that must be considered to evaluate if such a scheme is a reasonable course of action for compressor station methane emissions reduction. The study relies on both extensive literature review and model-based engine simulations to determine the feasibility of rebreathing crankcase gases in pursuit of reducing compressor station methane emissions. The conclusions of the study are limited to the crankcase vent rebreathing into the air intake of large bore, natural gas, 2-stroke engines. The model-based engine simulations require detailed physical geometry of the subject engines as well as knowledge of basic engine operating parameters (e.g., fuel flow, air flow, and fuel composition). The simulation is based on the experimental facility located at Colorado State University, which is a 4-cylinder Cooper-Bessemer GMV-4. One of the important parameters needing to be known is the gas composition of both compressor and engine crankcases. It is extremely difficult to determine the composition of the engine crankcase gases, since the composition depends on a large variety of parameters. For this study, the gases from the compressor crankcase are modeled as methane (i.e., pipeline gas), and the gases from the engine crankcase are modeled as products of combustion with two different levels methane concentration (1500 ppm and 3000 ppm). A sensitivity analysis is performed, and the observed pressure traces from the model-based engine simulation show that the engine performance is not affected by the addition of rebreathed gases. This insensitivity mainly results from the very small rebreathed flow rates compared to the air intake, and the adjustments made on engine parameters, boost pressure and fuel injection rate, to keep trapped equivalence ratio (TER) and the energy delivery rate the same.

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Hedrick, Jacob, and Timothy Jacobs. PR-457-14201-R02 Variable NG Composition Effects in LB 2S Compressor Engines Phase I Engine Response. Pipeline Research Council International, Inc. (PRCI), 2015. http://dx.doi.org/10.55274/r0010997.

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This is the final report summarizing work completed during the first phase of the PRCI study on large bore two stroke lean burn integral compressor engine response to variable natural gas compositions for the purposes of engine control development. Accomplished tasks include the completion of a detailed literature review covering the research topic, a parametric study of laminar flame speeds and ignition delays for binary methane and ethane mixtures up to 30%, and a GT-Power engine model of the Colorado State GMV-4 research engine with associated validation data from CSU�s variable ethane effects study. The chemistry of the combustion reaction is crucial to accurate modeling; laminar flame speeds and ignition delays as function of composition were determined from the solutions to published chemical kinetics mechanisms GRI-Mech3.0 and Saudi Aramco Mech1.3, respectively. The Wiebe coefficients correlated to variations in ethane composition and spark timing were regressed from the crank angle resolved heat release rates. The Wiebe coefficients are the most significant achievement of this phase of the project, since they quantify the heat release as a function of composition. At this time, the Wiebe parameters only reflect the relative changes in the model since certain aspect of the models geometry are pending resolution. Future phases of the project could use the developed GT-Power model and Wiebe coefficients for development of control schemes that maintain emissions, speed and torque limits, and maximize thermal efficiency during a variable fuel composition event.

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Hedrick and Jacobs. PR-457-14201-R01 Variable Natural Gas - Composition Effects and Control Methods for Two-Stroke Engines. Pipeline Research Council International, Inc. (PRCI), 2015. http://dx.doi.org/10.55274/r0010027.

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Literature is reviewed for the impacts of variable natural gas composition on two-stroke lean burn pipeline compressor engines. Information gathered for these engines can be simplified for development of control algorithms in four-stroke and richer burning engines. Data shows that geospatial, geological, and transient hydraulic effects cause composition variations that adversely affect engine emissions, efficiency, rated performance, and operational safety considering auto-ignition effects. In order to compensate for these changes in composition, better engine control schemes can help meet desired performance goals. For specific gas compositions combusting at a fixed air-fuel ratio, the laminar flame speed, adiabatic flame temperature, and ignition delay relate to and allow the prediction of the mixture�s reactivity, thermal availability, and auto-ignition tendency. Predicting changes in these combustion parameters, as caused by changes in fuel composition, is essential to the success of control development for variable composition engine operation. In addition to addressing the associated combustion effects resulting from variable fuel composition, an overview of sensor technologies is presented for use in control applications.

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Skelly, Andrea C., Eric Chang, Jessica Bordley, et al. Radiation Therapy for Metastatic Bone Disease: Effectiveness and Harms. Agency for Healthcare Research and Quality (AHRQ), 2023. http://dx.doi.org/10.23970/ahrqepccer265.

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Objectives. To evaluate the comparative effectiveness and harms of external beam radiation therapy (EBRT) for palliative treatment of metastatic bone disease (MBD). Data sources. Four electronic databases from 1985 to January 30, 2023; a targeted search for re-irradiation through January 30, 2023; reference lists; and a Federal Register notice. Review methods. Using predefined criteria and dual review, we selected randomized controlled trials (RCTs) and nonrandomized studies of interventions (NRSIs) comparing dose-fractionation schemes and EBRT delivery techniques (for initial radiation and re-irradiation, i.e., retreatment for recurrent or persistent pain) and EBRT alone versus in combination with other palliative treatments. Study risk of bias was assessed using predefined criteria. Strength of evidence (SOE) was assessed for the primary outcomes of pain, function, spinal cord compression relief, quality of life, and harms. Results. We included 53 RCTs and 31 NRSIs; most were fair quality. In patients receiving initial radiation for MBD there was a small increase in the likelihood of overall pain response (improved pain measures with stable or decreased analgesic use) for multiple fraction (MF) EBRT versus single fraction (SF) EBRT up to 4 weeks post-radiation therapy (SOE: moderate) and for higher dose (6 or 8 Gy) SF EBRT versus lower dose (4 Gy) SF EBRT up to 52 weeks post-radiation therapy (SOE: low). SF and MF EBRT did not differ at later followup (SOE: moderate) nor did comparisons of MF EBRT dose/fractions (SOE: moderate ≤12 weeks; low >12 weeks). Re-irradiation was more common with SF versus MF EBRT. Stereotactic body radiation therapy (SBRT) (SF or MF) was associated with a slightly higher (up to 20 weeks, SOE: low) and moderately higher (30 weeks; SOE: moderate) likelihood of overall pain response versus MF EBRT. For re-irradiation, SF and MF SBRT had a similar likelihood of overall pain response, as did SF versus MF EBRT (SOE: low for all). Harms may be similar across dose/fraction schemes and techniques; serious harms were rare. Comparative effectiveness evidence for EBRT was sparse. Conclusions. In patients with uncomplicated MBD receiving initial palliative radiotherapy, the likelihood of overall pain response for SF and MF EBRT is probably similar, particularly after 4 weeks; re-irradiation was more common with SF-EBRT. SF and MF SBRT may provide slightly greater likelihood of overall pain response versus MF EBRT; evidence is limited. SF and MF EBRT may have similar likelihoods of overall pain response in patients receiving re-irradiation. High-quality evidence comparing SBRT with EBRT is needed in populations with complicated and uncomplicated MBD, as is research on effectiveness of EBRT versus other treatments. Update: An addendum is located at the end of the main report, before the appendixes.

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Brandenberg, Scott, Jonathan Stewart, Kenneth Hudson, Dong Youp Kwak, Paolo Zimmaro, and Quin Parker. Ground Failure of Hydraulic Fills in Chiba, Japan and Data Archival in Community Database. Pacific Earthquake Engineering Research Center, University of California, Berkeley, CA, 2024. http://dx.doi.org/10.55461/amnh7013.

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This report describes analysis of ground failure and lack thereof observed in the Mihama Ward portion of Chiba, Japan following the 2011 M9.0 Tohoku Earthquake. In conjunction with this work, we have also significantly expanded the laboratory component of the Next Generation Liquefaction (NGL) relational database. The district referred to as Mihama Ward is on ground composed of hydraulic fill sluiced in by pipes, thereby resulting in a gradient of soil coarseness, with coarser soils deposited near the pipes and fine-grained soils carried further away. Observations from local researchers at Chiba University following the 2011 Tohoku Earthquake indicate that ground failure was observed closer to the locations where the pipes deposited the soil, and not further away. This ground failure consisted of extensive sand boiling and ground cracking, which led to building settlement and pipe breaks. Our hypothesis at the outset of the project was that liquefaction susceptibility might explain the pattern of ground failure. Specifically, soils deposited near the pipes are susceptible due to their coarser texture, while soils further from the pipes may be non-susceptible due to the presence of clay minerals and higher plasticity. Were this hypothesis borne out by evidence, soil in the transition zone would have provided important insights about liquefaction susceptibility. Based on testing of soils in our laboratory, we find this hypothesis to be only partially correct. We have confirmed that there are regions with high clay contents and no ground failure and other regions with predominantly granular soils and extensive surface manifestation of liquefaction. Where the hypothesis breaks down is in the transition zone, where we found that the fine-grained soils are non-plastic, and therefore they are susceptible to liquefaction. Our interpretation is that these silt materials likely liquefied during the earthquake, but did not manifest liquefaction. Two factors may have contributed to this lack of manifestation: (1) level ground conditions and lack of large driving static shear stresses (structures in the region are light residential construction) and (2) the silt is less likely to erode to the surface and form silt boils than the sandier soils that produced surface manifestations. This case history points to the importance of separating triggering (defined as the development of significant excess pore pressure and loss of strength) from manifestation (defined as observations of ground failure, including cracking, sand boils, and lateral spreading). The Mihama Ward case history involved laboratory tests performed by Tokyo Soil Research Co. Ltd. and the UCLA geotechnical laboratory. Given the importance of this data to the understanding of this case history, we recognized a need to incorporate laboratory tests in the NGL database alongside field tests and liquefaction observations. We therefore developed an organizational structure for laboratory tests, including direct simple shear, triaxial compression, and consolidation, and implemented the schema in the NGL database. We then uploaded data from tests performed by Tokyo Soil and UCLA. Furthermore, numerous other researchers have also uploaded laboratory test data for other sites. This report describes the organizational structure of the laboratory component of the database, and a tool for interacting with laboratory data.

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