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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

A comparison study of the implementation of digital camera's RAW and JPEG and scanner's TIFF file formats, and color management procedures for inkjet textile printing applications /

Chien, Chi-Hao. January 2009 (has links)
Thesis (M.F.A.)--Rochester Institute of Technology, 2009. / Typescript. Includes bibliographical references (leaves 58-61).
22

Compressing scientific data with control and minimization of the L-infinity metric under the JPEG 2000 framework

Lucero, Aldo. January 2007 (has links)
Thesis (Ph. D.)--University of Texas at El Paso, 2007. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.
23

Digital rights management (DRM) : watermark encoding scheme for JPEG images

Samuel, Sindhu. January 2007 (has links)
Thesis (M.Eng. (Electrical, Electromic and Computer Engineering)) -- University of Pretoria, 2007. / Includes bibliographical references (leaves 82-87)
24

Détection statistique d'information cachée dans des images naturelles / Statistical detection of hidden information in natural images

Zitzmann, Cathel 24 June 2013 (has links)
La nécessité de communiquer de façon sécurisée n’est pas chose nouvelle : depuis l’antiquité des méthodes existent afin de dissimuler une communication. La cryptographie a permis de rendre un message inintelligible en le chiffrant, la stéganographie quant à elle permet de dissimuler le fait même qu’un message est échangé. Cette thèse s’inscrit dans le cadre du projet "Recherche d’Informations Cachées" financé par l’Agence Nationale de la Recherche, l’Université de Technologie de Troyes a travaillé sur la modélisation mathématique d’une image naturelle et à la mise en place de détecteurs d’informations cachées dans les images. Ce mémoire propose d’étudier la stéganalyse dans les images naturelles du point de vue de la décision statistique paramétrique. Dans les images JPEG, un détecteur basé sur la modélisation des coefficients DCT quantifiés est proposé et les calculs des probabilités du détecteur sont établis théoriquement. De plus, une étude du nombre moyen d’effondrements apparaissant lors de l’insertion avec les algorithmes F3 et F4 est proposée. Enfin, dans le cadre des images non compressées, les tests proposés sont optimaux sous certaines contraintes, une des difficultés surmontées étant le caractère quantifié des données / The need of secure communication is not something new: from ancient, methods exist to conceal communication. Cryptography helped make unintelligible message using encryption, steganography can hide the fact that a message is exchanged.This thesis is part of the project "Hidden Information Research" funded by the National Research Agency, Troyes University of Technology worked on the mathematical modeling of a natural image and creating detectors of hidden information in digital pictures.This thesis proposes to study the steganalysis in natural images in terms of parametric statistical decision. In JPEG images, a detector based on the modeling of quantized DCT coefficients is proposed and calculations of probabilities of the detector are established theoretically. In addition, a study of the number of shrinkage occurring during embedding by F3 and F4 algorithms is proposed. Finally, for the uncompressed images, the proposed tests are optimal under certain constraints, a difficulty overcome is the data quantization
25

Securing digital images

Kailasanathan, Chandrapal. January 2003 (has links)
Thesis (Ph.D.)--University of Wollongong, 2003. / Typescript. Includes bibliographical references: leaf 191-198.
26

A study of image compression techniques, with specific focus on weighted finite automata

Muller, Rikus 12 1900 (has links)
Thesis (MSc (Mathematical Sciences)--University of Stellenbosch, 2005. / Image compression using weighted finite automata (WFA) is studied and implemented in Matlab. Other more prominent image compression techniques, namely JPEG, vector quantization, EZW wavelet image compression and fractal image compression are also presented. The performance of WFA image compression is then compared to those of some of the abovementioned techniques.
27

PCA and JPEG2000-based Lossy Compression for Hyperspectral Imagery

Zhu, Wei 30 April 2011 (has links)
This dissertation develops several new algorithms to solve existing problems in practical application of the previously developed PCA+JPEG2000, which has shown superior rate-distortion performance in hyperspectral image compression. In addition, a new scheme is proposed to facilitate multi-temporal hyperspectral image compression. Specifically, the uniqueness in each algorithm is described as follows. 1. An empirical piecewise linear equation is proposed to estimate the optimal number of major principal components (PCs) used in SubPCA+JPEG2000 for AVIRIS data. Sensor-specific equations are presented with excellent fitting performance for AVIRIS, HYDICE, and HyMap data. As a conclusion, a general guideline is provided for finding sensor-specific piecewise linear equations. 2. An anomaly-removal-based hyperspectral image compression algorithm is proposed. It preserves anomalous pixels in a lossless manner, and yields the same or even improved rate-distortion performance. It is particularly useful to SubPCA+JPEG2000 when compressing data with anomalies that may reside in minor PCs. 3. A segmented PCA-based PCA+JPEG2000 compression algorithm is developed, which spectrally partitions an image based on its spectral correlation coefficients. This compression scheme greatly improves the rate-distortion performance of PCA+JPEG2000 when the spatial size of the data is relatively smaller than its spectral size, especially at low bitrates. A sensor-specific partition method is also developed for fast processing with suboptimal performance. 4. A joint multi-temporal image compression scheme is proposed. The algorithm preserves change information in a lossless fashion during the compression. It can yield perfect change detection with slightly degraded rate-distortion performance.

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