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Tesi sul tema "Holographic image"

Autore: Grafiati

Pubblicato: 4 giugno 2021

Ultima modifica: 9 febbraio 2022

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1

Kim, Taegeun. "Optical Three-Dimensional Image Matching Using Holographic Information". Diss., Virginia Tech, 2000. http://hdl.handle.net/10919/28362.

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We present a three-dimensional (3-D) optical image matching technique and location extraction techniques of matched 3-D objects for optical pattern recognition. We first describe the 3-D matching technique based on two-pupil optical heterodyne scanning. A hologram of the 3-D reference object is first created and then represented as one pupil function with the other pupil function being a delta function. The superposition of each beam modulated by the two pupils generates a scanning beam pattern. This beam pattern scans the 3-D target object to be recognized. The output of the scanning system gives out the 2-D correlation of the hologram of the reference object and that of the target object. When the 3-D image of the target object is matched with that of the reference object, the output of the system generates a strong correlation peak. This theory of 3-D holographic matching is analyzed in terms of two-pupil optical scanning. Computer simulation and optical experiment results are presented to reinforce the developed theory. The second part of the research concerns the extraction of the location of a 3-D image matched object. The proposed system basically performs a correlation of the hologram of a 3-D reference object and that of a 3-D target object, and hence 3-D matching is possible. However, the system does not give out the depth location of matched 3-D target objects directly because the correlation of holograms is a 2-D correlation and hence not 3-D shift invariant. We propose two methods to extract the location of matched 3-D objects directly from the correlation output of the system. One method is to use the optical system that focuses the output correlation pattern along depth and arrives at the 3-D location at the focused location. However, this technique has a drawback in that only the location of 3-D targets that are farther away from the 3-D reference object can be extracted. Thus, in this research, we propose another method in which the extraction of a location for a matched 3-D object is possible without the aforementioned drawback. This method applies the Wigner distribution to the power fringe-adjusted filtered correlation output to extract the 3-D location of a matched object. We analyze the proposed method and present computer simulation and optical experiment results.
Ph. D.

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2

Yang, Hui. "Data extraction in holographic particle image velocimetry". Thesis, Loughborough University, 2004. https://dspace.lboro.ac.uk/2134/35012.

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Holographic Particle Image Velocimetry (HPIV) is potentially the best technique to obtain instantaneous, three-dimensional, flow field information. Several researchers have presented their experimental results to demonstrate the power of HPIV technique. However, the challenge to find an economical and automatic means to extract and process the immense amount of data from the holograms still remains. This thesis reports on the development of complex amplitude correlation as a means of data extraction. At the same time, three-dimensional quantitative measurements for a micro scale flow is of increasing importance in the design of microfluidic devices. This thesis also reports the investigation of HPIV in micro-scale fluid flow. The author has re-examined complex amplitude correlation using a formulation of scalar diffraction in three-dimensional vector space.

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3

Plaisted, Parker Bennett. "An investigation of point image analysis for evaluating holographic image quality /". Online version of thesis, 1993. http://hdl.handle.net/1850/11878.

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4

Earls, Craig P. "Holographic particle image velocimetry : computational simulation and reconstruction". Thesis, Springfield, Va. : Available from National Technical Information Service, 1999. http://handle.dtic.mil/100.2/ADA372219.

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Thesis (Degree of Naval Engineer and M.S. in Aerospace Engineering) Massachusetts Institute of Technology, June 1999.
"June 1999". Includes bibliographical references (leaves 77-79). Also available online.

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5

Holzbach, Mark. "Three-dimensional image processing for synthetic holographic stereograms". Thesis, Massachusetts Institute of Technology, 1986. http://hdl.handle.net/1721.1/14767.

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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1987.
Bibliography: leaves 54-55.
A digital image processing technique is presented that allows conventionally produced images to be prepared for undistorted printing in one-step holographic stereograms. This technique effectively predistorts the source 2D image set for a holographic stereogram to compensate for the distorting effects of its display geometry. The resulting stereograms can have undistort ed images that occupy space in front, back, and through the hologram surface. This technique is much more convenient that the current alternatives which either require unusual large optics, or much more intensive use of computer resources. It should therefore facilitate the fast and convenient production of one-step stereograms which are excellent 3D hardcopy displays with potential for applications that require fast visual communication of complex 3D information.
by Mark Holzbach.
M.S.

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6

Earls, Craig P. (Craig Paul) 1967. "Holographic particle image velocimetry : computational simulation and reconstruction". Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/80189.

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Thesis (Nav.E.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1999.
Includes bibliographical references (leaves 78-80).
by Craig P. Earls.
S.M.
Nav.E.

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7

Miller, Bo E., e Yuzuru Takashima. "Cavity enhanced image recording for holographic data storage". SPIE-INT SOC OPTICAL ENGINEERING, 2016. http://hdl.handle.net/10150/622715.

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Previously, we proposed and experimentally demonstrated that optical cavities can be employed in recording and readout of plane wave holograms to improve data rates in Holographic Data Storage Systems (HDSS). However, there were some concerns about whether these techniques would be applicable to page based HDSS where signal beams are image bearing and have multiple wave vectors. We have consequently demonstrated cavity enhanced writing of image bearing holograms in Fe: LiNbO3 with a 532 nm wavelength, CW, single mode, DPSS, Nd: YAG, laser with a cavity on the reference arm. The diffraction efficiency was monitored by pseudo-phase-conjugate readout during the recording process. Additionally, standing wave cavity recording was described as inappropriate to HDSS due to introducing additionally gratings to the recording process. The balancing of these grating strengths is analyzed relative to a trade-off in dynamic range consumption vs. data rates and the elimination of the extra gratings via quarter wave plates and isotropic recording media is proposed.

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8

McKeague, Thomas Anderson. "Holographic particle image velocimetry of ink jet streams". Thesis, Durham University, 2015. http://etheses.dur.ac.uk/10997/.

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Ink jet technology is a rapidly growing and diverse field of research. Ink jets are used to deliver very precise and small (picolitre) volumes of fluid to a surface. Recent advances in ink jet technology demand a better understanding of the dynamics of the fluid during jetting. The aim of this project was to design a method capable of measuring the flow velocities inside ink jet streams. This objective has been achieved by the use of digital holographic particle image velocimetry. The difficulty with measuring flows inside tightly curved samples is that the refractive index change over the boundary leads to an optical distortion and therefore particles cannot be viewed or tracked reliably. Optical distortion is compensated for by taking advantage of the ability to replay a holographically recorded wave. The light scattered by particles is propagated numerically back through the sample’s surface, to form a three-dimensional image in which all refractions at the interface have been accounted for. Three dimensional particle fields are then analysed using custom particle detection and correlation code to extract the displacement of individual particles between exposures, which facilitates the construction of full flow profiles. Holograms were recorded with a simple off-axis holographic microscope, comprising two point sources of divergent light, formed from the same objective lens, acting as the source of illumination and reference light, respectively. Experiments were conducted on continuous ink jet streams of water issuing from a nozzle with 100 µm diameter. For a few millimetres after the nozzle exit, the jet is cylindrical, it then starts to form swells and necks; the swells continue to grow at the expense of the necks until the jet breaks up into a stream of droplets. Measurements of the stream wise component of velocity have been successful in the cylindrical parts of the jet, in swells and in necks greater than 20 µm in diameter. To my knowledge measurements of particle velocities on fluid jets at this scale have not been accomplished previously.

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9

Degirmenci, Yilmaz. "Reasoning by analogy using holographic conceptual projection". Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2002. http://library.nps.navy.mil/uhtbin/hyperion-image/02sep%5FDegirmenci.pdf.

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10

Wormald, S. Andrew. "Numerical techniques in digital microscopic holographic particle image velocimetry". Thesis, Loughborough University, 2010. https://dspace.lboro.ac.uk/2134/7140.

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Digital microscopic holographic particle image velocimetry (DµHPIV) is a technique which records scattered coherent light and uses it to measure displacement of particles in a fluid flow. The work in this thesis begins with the construction of a digital holographic microscope and explores the different possible methods of recording and holographic reconstruction, finding an off-axis forward-scatter geometry to be most suitable for the task. A comparison follows of methods to measure displacement in a sparsely seeded environment by performing a simple experiment. It finds that complex amplitude correlation performs significantly better than both intensity correlation and nearest neighbour analysis; the two other possible methods of displacement tracking. Later, an experiment is performed to investigate the behaviour of a microfluidic blood separator. The separator is intended to remove blood plasma from whole blood without other contaminants such as red blood cells and without the need for expensive laboratory equipment. In this chapter a new technique, higher order correlation, is introduced which can be used to strengthen the peaks in correlations of three or more particle images in a flow, and a potential flow CFD model of the separator is built from scratch to predict whether the separator will work, and against which the results can be compared. Finally, there is an experiment carried out which for the first time allows aberration free imaging within objects with irregular, highly curved surfaces; in this case optical fibres and inkjet droplets, by numerically reconstructing the droplet surface.

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11

Bishop, Alexis Ivan. "Spectrally selective holographic interferometry techniques for flow diagnostics /". [St. Lucia, Qld.], 2001. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16305.pdf.

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12

Nelson, Kathryn M. (Kathryn Marie). "Real time holographic image rendering : improvements in lighting and realism". Thesis, Massachusetts Institute of Technology, 1993. http://hdl.handle.net/1721.1/33812.

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13

Chen, Jhen-Si. "Holographic 3D image display : layer-based method and coarse integrated holograms". Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708806.

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14

Feng, Z. "A signal processing method for the acoustic image reconstruction of planar objects". Thesis, University of Portsmouth, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234728.

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15

Dawson, Paula Heatley Art College of Fine Arts UNSW. "The Concrete Holographic Image: an Examination of Spatial and Temporal Properties and their Application in a Religious Art Work". Awarded by:University of New South Wales. School of Art, 2000. http://handle.unsw.edu.au/1959.4/18201.

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Abstract (sommario):

The premise of this thesis is that the ???concrete holographic image???, a laser transmission hologram which has an object or a hologram of an object as its subject, has unique spatial and temporal properties which can suggest a plurality of tenses to a viewer. There is a lack of comprehensive analysis of the holographic representational system within art related theoretical and critical writing and a tendency to analyse individual works only in terms of generalities which apply to the concepts surrounding the holographic medium. While these form an important background for art image production, in some cases corresponding to artists works, the existing written material on the subject is inadequate as a model from which to draw the all important temporal conclusions. To date the critical reception of holograms has made no mention of acuity, the size of the viewing frustum, the depth of the image and scant mention of interference phenomena which are the intrinsic factors which I believe precipitate temporal illusions. Therefore this thesis examines the concrete holographic image in great detail on its own terms, firstly through theories of the basic image forming phenomena of interference and diffraction and secondly through the techniques of production as they have been adapted for the making of my art works. The extent of the metaphorical and allegorical potential of the spatial and temporal properties of the concrete holographic image are put to the ultimate test in a commission for St Brigid???s Church, Coogee. The Shrine of the Sacred Heart commission for St Brigid???s requires a concrete holographic image to facilitate devotion to the Sacred Heart. The Sacred Heart is not a physical thing but a complex, evolving spiritual entity with a realist pictorial history.

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16

Ross, Gary A. "A study of the quality of holographic real images with the introduction of image point aberrations". Thesis, University of Aberdeen, 1994. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU058718.

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The aim of this work is to investigate the effects of deviations from the ideal reconstruction on the quality of the holographic real image. The deviations include varying the angle of incidence of the reconstruction beam, varying the distance of the source of that beam, altering its wavelength from that of the recording, and changing the medium in which the hologram is replayed with respect to that in which it was recorded. From the results, the tolerance of several common recording geometries to these changes were evaluated and recommendations made as to which of the geometries are most suitable for use in the recording of holograms of which will result in images of the highest quality with respect to resolution and dimensionality for objects covering narrow and wide field angles. This is done for both in-air and underwater holograms. It is also the aim to evaluate the quality of each image theoretically to find the relationship between the ideal and the practically observed image resolutions. The theoretical values were calculated utilising third-order approximations based on work by Meier (1) and Champagne (2) to obtain coefficients for each of the point image aberrations present thus determining which of the aberrations are present for each variation in each goemetry and which determine the extent of the reduction in the quality of the image. These results were utilised in ensuing calculations of image resolution for each of the recording / reconstruction geometry combinations which exploit the aberration tolerance conditions proposed in the work by Born and Wolf(3). These theoretical values of resolution are compared to those found experimentally and reasons for discrepancies suggested.

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17

Clapham, Sarah Louise. "Real-time holographic display devices for image projection and spatial light modulation". Thesis, University of Southampton, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293148.

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18

Naidoo, Thegaran. "Digital holographic microscopy with automated detection of red blood cells". Diss., University of Pretoria, 2017. http://hdl.handle.net/2263/61032.

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The digital in-line holographic configuration is motivated by the goal of developing a portable, cost effective sensor system for pre-screening patient blood samples. The theory of holography is explained from the foundational concepts in scalar diffraction theory all the way through to the implementation of reconstruction algorithms. Methods for the enhancement of holographic reconstructions are described. The algorithms that perform an automated count of the reconstructed objects are described and demonstrated. Simulated and experimental results are provided. Together, the lens-free holographic microscopy of micro-sized particles along with the application of image processing techniques for the automated detection and counting of objects of interest, provide a component towards realising a sensor system that can be used for pre-screening patient blood samples.
Dissertation (MSc)--University of Pretoria, 2017.
CSIR
Computer Science
MSc
Unrestricted

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19

Kocher, C. J. "A study of the effects of processing chemistry on the holographic image space". Thesis, University of Brighton, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383653.

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20

Sorensen, Thomas J. "Inverse Scattering Image Quality with Noisy Forward Data". Diss., CLICK HERE for online access, 2008. http://contentdm.lib.byu.edu/ETD/image/etd2541.pdf.

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21

Eichmann, Troy N. "An experimental investigation of shock shapes and shock stand-offs in a super-orbital facility /". [St. Lucia, Qld.], 2003. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18122.pdf.

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22

Kvasnica, Lukáš. "Řízení optického stolku interferenčního mikroskopu na základě obrazové fáze". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2008. http://www.nusl.cz/ntk/nusl-228199.

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Digital holographic microscopy is an interferometric imaging technique, the principle of which is the off-axis image plane holography. The principle of this technique enables to reconstruct both the image intensity and the image phase from the output interferencesignal. The reconstruction can be carried out on the basis of a single image plane hologram. This leads to the possibility of a realtime image reconstruction. The speed of the reconstruction depends on the detection and the computing process. The aim of this diploma thesis is to develop user software for the control of the detection camera and for the image plane hologram reconstruction. The effort was to achieve the highest number of image reconstructions per time unit, with the maximum utilization of the data transfer between the camera and the computer.The next aim of this thesis is the stabilization of the optical table position. The method of stabilization is based on the image phase information, which is used for the control loop feedback between reconstructed image phase and the piezoelectric actuator placed inside of the optical table. Experimental results, which prove the functionality of the stabilization, are presented.

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23

Boussemaere, Luc. "Investigating off-axis digital holographic microscopy with a source of partial spatial coherence as a real-time sensor for cell cultures". Doctoral thesis, Universite Libre de Bruxelles, 2015. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209086.

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Bio-pharmaceutical industry is a vast growing market and recent recommendations of the Food and Drug Administration have put a large emphasis on the characterization of biological processes and models. As a consequence, there is a high incentive on developing modern sensors in order to more accurately monitor and control processes. In that way, Digital Holographic Microscopy (DHM) presents unique features thanks to the refocusing and quantitative phase contrast imaging capabilities. In this thesis we investigate the usage of DHM to monitor yeast cultures that are often used in both the bio-pharmaceutical and bread industries and lay the basis of a methodological framework for the study of in-line cell cultures in the context of process control. We begin with a description of Digital Holography and the microscopy setup used in the thesis as well as a detailed explanation of the image processing required to extract the holographic data and its implementation on GPU with some speed execution figures given for three popular programming paradigms. We then describe the flow setup used and infer the limitations on the dynamic range of the technique due to both Poisson statistics and overlapping phenomena. Finally, we describe an algorithm that extracts the cells position, count and morphological information such as the size, aspect ratio, circularity and refraction index. Some experimental results are presented for yeasts before drawing a general overview of the technology and its dependencies. We further end with some conclusions concerning the technology and a brief comparison with existing competitors.
Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished

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24

Vašíček, David. "Fluorescenční zobrazovací techniky v multimodálním holografickém mikroskopu". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2014. http://www.nusl.cz/ntk/nusl-231466.

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The diploma thesis deals with the registration of images taken with the multimodal holographic microscope (MHM). The summary covers the fluorescent and holographic microscopy, and the multimodal holographic microscope combining both these microscopy types. Every pair of the images needs to be aligned in order to gain new information by combining both image types. The thesis contains an algorithm that registers images by phase correlation as well as a process created in MATLAB in accordance with the algorithm. The most important procedure parameters’ influence on the registration success is described and the results are annotated.

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25

Connors, Betsy. "Holographic moving images". Thesis, Massachusetts Institute of Technology, 1986. http://hdl.handle.net/1721.1/65217.

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26

Monnom, Olivier. "Méthodes algorithmiques de traitement d'images en holographie digitale". Doctoral thesis, Universite Libre de Bruxelles, 2006. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210840.

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Le présent travail traite de problèmes particuliers en traitement de signal soulevés par l'holographie digitale. Le premier chapitre présente l'holographie et l'holographie digitale. Le deuxième chapitre aborde le problème des artéfacts apparaissant sur le bord des hologrammes lorsque ceux-ci sont propagés numériquement. Le troisième chapitre propose une méthode automatique pour éliminer la phase de fond d'un hologramme. Le quatrième chapitre montre comment améliorer la visibilité des hologrammes en supprimant les objets diffractants. Le cinquième chapitre expose un logiciel d'aide à l'analyse des hologrammes enregistrés dans le temps. On montre la capacité du logiciel à effectuer du tracking d'objets en trois dimensions à posteriori. Le sixième chapitre traite de la reconnaissance de forme dans les hologrammes, le problème de la reconnaissance de particules micrométriques est abordé. Des conclusions et perspectives terminent le travail.
Doctorat en sciences appliquées
info:eu-repo/semantics/nonPublished

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27

Rew, Gayle Astrid Adele. "Studies in zone plate encoded holography with high energy gamma rays". Thesis, University of Birmingham, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366166.

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28

Štrbková, Lenka. "Biofyzikální interpretace kvantitativního fázového zobrazení". Doctoral thesis, Vysoké učení technické v Brně. CEITEC VUT, 2018. http://www.nusl.cz/ntk/nusl-369740.

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Práce se zabývá interpretací kvantitativního fázového zobrazení pomocí techniky koherencí řízené holografické mikroskopie. Vzhledem k tomu, že tato technika generuje velké množství kvantitativních fázových obrazů o nezanedbatelné velikosti, manuální analýza by byla časově náročná a neefektivní Za účelem urychlení analýzy obrazů získaných pomocí koherencí řízené holografické mikroskopie je v této práci navržena metodika automatizované interpretace kvantitativních fázových obrazů pomocí strojového učení s učitelem. Kvantitativní fázové obrazy umožňují extrakci parametrů charakterizujících distribuci suché hmoty v buňce a poskytují tak cennou informaci o buněčném chování. Cílem této práce je navrhnout metodologii pro automatizovanou klasifikaci buněk při využití této kvantitativní informace jak ze statických, tak z časosběrných kvantitativních fázových obrazů. Navržená metodika byla testována v experimentech s živými buňkami, jimiž byla vyhodnocena výkonnost klasifikace a významnost parametrů získaných z kvantitativních fázových obrazů.

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Kuhlmann, Abrantes Juliana. "Vélocimétrie par Image de Particules Holographique pour les Mesures de Turbulence de Paroi". Phd thesis, Ecole Centrale de Lille, 2012. http://tel.archives-ouvertes.fr/tel-00862796.

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La compréhension de la dynamique de la turbulence de paroi a déjà fait l'objet de nombreuses études expérimentales et numériques depuis des décennies. Le principal intérêt pratique de ces études tient au fait que la contrainte de cisaillement pariétale (et donc le frottement) est étroitement liée à la dynamique des structures à la proximité de la paroi. Les techniques expérimentales en mécanique des fluides ont également fait de grands progrès ces dernières années. Ce travail présente le développement d'une méthode expérimentale visant à fournir des mesures 3D-3C de l'écoulement dans la région de très proche paroi, en vue de mesurer la contrainte de cisaillement à la paroi avec une précision améliorée. Dans ce but, une technique originale de Vélocimétrie Holographique par Images de Particules a été mise au point. Les mesures sont effectuées dans un petit volume à proximité de la paroi dans la soufflerie au Laboratoire de Mécanique de Lille. Des mesures détaillées dans un de l'ordre de 1.5mm3 sont rendues possibles grâce l'utilisation d'un objectif de microscope pour l'agrandissement du champ objet. Les particules sont éclairées par le côté, la lumière diffusée a 90o se recombine avec l'onde de référence pour un enregistrement holographique en ligne de type Gabor. Une procédure d'étalonnage a été développée afin de relier l'espace de reconstruction de l'image holographique aux coordonnées dans le volume de mesure. L'analyse des résultats montre que les images de particules sont reconstruites avec une très bonne résolution axiale, ce qui conduit à penser que la configuration est bien adapté à cette type de mesure. Ces résultats montrent également qu'une optimisation et des ajustements sont nécessaires pour d'améliorer les résultats de suivi de particules

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Lebon, Benoît. "Etude 3D d’un tourbillon dans un champ de houle par holographie numérique". Thesis, Normandie, 2017. http://www.theses.fr/2017NORMLH22/document.

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Cette thèse traite de l'application de l'holographie numérique dans l'axe à l'étude d'une dynamique tourbillonnaire dans un champ de houle. Lors du passage de la houle au dessus d'une structure immergée, des tourbillons se forment à ses extrémités. Ces tourbillons ont un impact fort sur la dynamique proche des structures et peuvent engendrer des problèmes d'affouillement ou de vieillissement prématuré. On s'intéresse donc à la dynamique tridimensionnelle de ces tourbillons qui sont rapidement l'objet de déformations menant à leur éclatement. Pour étudier ce mécanisme, le problème est modélisé par une géométrie simple, une plaque soumise à une houle monochromatique. Les expériences sont menées dans un canal à houle de 10 m de long et 30 cm de large. Pour mesurer la dynamique 3D on utilise une technique innovante, l'holographie numérique qui permet une mesure 3D3C au moyen d'une diode laser et d'une seule caméra. Ses principales limitations résident dans la dimension de la section du volume de mesure, qui est de l'ordre de la surface du capteur CCD, ainsi que du nombre de particules présentes dans le champ. Toutefois, l'holographie permet une résolution de l'ordre de la taille d'un pixel dans le plan du capteur CCD et de 3 à 5 fois le diamètre de la particule suivie dans la direction orthogonale au capteur. Ces mesures permettent de suivre individuellement plusieurs centaines de particules dans le champ et d'en mesurer les vitesses. Enfin des mesures complémentaires en stéréo-piv confirment les résultats obtenues par holographie et permettent l'étude du confinement du tourbillon sous l'action combinée de la surface libre et de la plaque
This thesis deals with the use of digital in-line holography to the study of a vortex dynamics under water waves. As waves propagate above an immersed structure, vortices are formed at its edges. Those vortices have a strong impact on the flow dynamics in the vicinity of structures and can cause scouring or damages. Thus we are interested in the three-dimensional dynamics of those vortices which are quickly distorted, leading to their breakup. To study this dynamics, the physical problem is modelled by a basic geometry, a thin plate is set under monochromatic waves. Experiments are conduct within a wave flume of dimensions 10 m long and 30 cm width. To measure the 3D flow the use of an innovative technique, the digital holography which allow a 3D3C measure with only one camera and a laser diode. Its main limitations are the size of the cross-section of the sample volume and the number of particles allowed in it. However, digital holography can localize particles with a pixel sized resolution within the plans parallel to the CCD sensor and a depth resolution in the order of 3 to 5 times the particles diameter. Those measurements enable to follow the path of each particle inside the sample volume. Finally, acquisition by stereo particle image velocimetry confirms the velocities measured by holography and are used to study the interaction between the vortex and the combined action of free surface and the plate

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31

Magalhães, Daniel Souza Ferreira. "Construção de telas holográficas e aplicações". [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/278163.

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Orientador: Jose Joaquín Lunazzi
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Fisica Gleb Wataghin
Made available in DSpace on 2018-08-14T06:28:04Z (GMT). No. of bitstreams: 1 Magalhaes_DanielSouzaFerreira_D.pdf: 18841445 bytes, checksum: 83953f45dd82288807d2ece70a0d3c17 (MD5) Previous issue date: 2009
Resumo: A Tela holográfica é um elemento óptico difrativo gerado pela interferência de dois feixes de maneira a redistribuir convenientemente para um observador a luz que recebe com o objetivo de visualização de imagens sem óculos e com paralaxe. Neste trabalho descrevemos alguns métodos de obtenção de telas holográficas para aplicações em projeções com luz branca. As fundamentamos, analisamos os resultados obtidos, assim como descrevemos suas aplicações.
Abstract: Holographic screen is a difractive optical element generated by the interference of two beams in order to properly distribute to an observer the light it receives with the purpose of viewing parallax images without glasses. This work describes some methods for obtaining holographic screens looking forward applications with white light. We substantiate, analyze the results and describe their applications.
Doutorado
Ótica
Doutor em Ciências

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Ziegler, Remo. "Holography and wave-based image generation /". Zürich : ETH, 2008. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17823.

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33

Zhang, Xin, e 张鑫. "Sectional image reconstruction in optical scanning holography". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B4476487X.

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Doh, Kyu-Bong. "Twin-image problems in optical scanning holography". Diss., Virginia Tech, 1996. http://hdl.handle.net/10919/39169.

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35

Tziraki, Maria. "The development of photorefractive holography through turbid media for application to biomedical imaging". Thesis, Imperial College London, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341934.

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36

Hawryszkiw, Jean. "Traitement d'images hybride pour l'analyse qualitique et metrologique de structures". Université Louis Pasteur (Strasbourg) (1971-2008), 1986. http://www.theses.fr/1986STR13320.

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Methodologie d'exploitation de l'information fournie par les techniques photoniques globales telles que l'interferometrie holographique, le moire ou la thermographie ir. Cette methodologie a ete validee par l'etude et la mise au point d'un systeme hybride photonique-informatique d'interpretation d'interferogrammes holographiques

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37

Harris, Michael C. "Development of an Energy-Based Nearfield Acoustic Holography System". Diss., CLICK HERE for online access, 2005. http://contentdm.lib.byu.edu/ETD/image/etd835.pdf.

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38

Gardner, Michael D. "Scan-Based Near-Field Acoustical Holography on Partially Correlated Sources". Diss., CLICK HERE for online access, 2009. http://contentdm.lib.byu.edu/ETD/image/etd3167.pdf.

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Shepherd, Micah Raymond. "The Effect of Nonlinear Propagation on Near-field Acoustical Holography". Diss., CLICK HERE for online access, 2007. http://contentdm.lib.byu.edu/ETD/image/etd2072.pdf.

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40

Binfield, Peter. "The effects of silver halide processing schemes on image fidelity in hologrammetry". Thesis, University of Aberdeen, 1994. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU541140.

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An investigation is conducted into the suitability of thirteen different silver halide hologram development schemes with a view towards their use in underwater hologrammetry. To this end the image fidelity indicators of resolution, reconstructed irradiance, noise, signal-to-noise ratio and contrast are extracted from a representative, diffusely reflecting object. Both amplitude and phase holograms are recorded, utilising a range of post-development treatments, on Agfa-Gevaert 8E56 emulsion. In addition, silver halide sensitised gelatin holograms are examined and evaluated. The major conclusion drawn is that suitably chosen phase development schemes are able to outperform amplitude development schemes in each fidelity indicator. A smaller number of development schemes are selected and characterised in terms of repeatability, beam ratio variations, Hurter-Driffield curves, 'amplitude transmittance versus exposure' curves and hologrammetric suitability. Pulsed holograms are recorded of the representative object both in-air and underwater. These holograms are evaluated with a view to determining their comparability and the conclusion is drawn that underwater holograms, in ideal conditions, are equivalent to 'in-air' holograms. It is concluded that, of those tested, the most suitable development scheme for underwater hologrammetry is Tetenal Neofin Blue bleached (without fixation) with ferric EDTA rehalogenating bleach. The optimum beam ratio is when K=5 and the optimum exposure for maximum signal-to-noise ratio, accurate contrast reproduction and high resolution is H = 25 muJ cm-2. Should maximum resolution be required then exposures as low as H = 5 muJ cm-2 should be employed.

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41

Raouf, Abdul. "Three dimensional image structure in in-line Fraunhofer holography". Thesis, Brunel University, 1991. http://bura.brunel.ac.uk/handle/2438/7278.

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In this thesis a new theoretical model for the three dimensional images from a finite aperture in-line Fraunhofer hologram is presented. Existing work only deals with the case of single object, in this thesis this work has been extended to the case of two identical coplanar discs. The resulting image equation is solved numerically for several different limiting apertures and their results are compared with the image intensity data from the holograms recorded on Agfa BE 75HD film. Excellent quantitative agreement is found, verifying the theoretical predictions. Three different criteria for determining the disc diameter and disc separation describing their errors are discussed for both numerical and experimental data. A data acquisition system based upon a digital interfaced with a PC, and high resolution video camera is described.

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42

BENKHEROUROU, SAHNOUNE SOURAYA. "Contribution a l'uniformisation du faisceau laser gaussien collimate par holographie numerique". Université Louis Pasteur (Strasbourg) (1971-2008), 1988. http://www.theses.fr/1988STR13084.

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Presentation de deux techniques pour uniformiser le faisceau. La premiere est fondee sur le filtrage lineaire dans le domaine des frequences ou le faisceau est considere comme etant l'objet pouvant etre modifie par un filtre (hologramme) pour produire l'image filtree (faisceau uniforme). La seconde est constituee par deux filtres de phase. Le premier filtre sert a devier les rayons lumineux de facon a obtenir une repartition uniforme. Le second permet de collimater le faisceau deja uniformise par le premier

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43

Fonquernie, Marc. "Stabilite des ecoulements de convection naturelle en espace confine a fort nombre de rayleigh : une etude experimentale". Toulouse 3, 1987. http://www.theses.fr/1987TOU30185.

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Evaluaiton des champs thermiques de convection et des regimes d'ecoulement (pour un nombre de rayleigh superieur a 10**(10)) dans une piece d'habitation caracterisee par des conditions de temperatures de surface : un mur vertical chaud, le mur oppose froid et les quatre autres faces a la meme temperature

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Dahhan, A. K. "Real-time microwave holography using glow discharge detectors". Thesis, Cardiff University, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356739.

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45

Welsh, Thomas V. "Quantitative Analysis of 3D Images Formed Using Range Compressed Holography". University of Dayton / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1512317926568769.

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46

Woolston, Scott R. "Development of methods to propagate energy density and predict farfield directivity using nearfield acoustic holography /". Diss., CLICK HERE for online access, 2009. http://contentdm.lib.byu.edu/ETD/image/etd3016.pdf.

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47

Ubaldi, Filippo <1977&gt. "Simulations and interpretation of holographic TEM images of biased and unbiased electronic devices". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/2195/.

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48

Laforest, Timothé. "Nouveaux dispositifs intégrés pour l'analyse et le contrôle de lumière cohérente : conception conjointe de circuits opto-électroniques et systèmes optiques". Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENT113/document.

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Parmi les techniques d'imagerie optiques utilisées en milieu clinique, la principale limitation est la faible résolution lorsque la profondeur d'examen dépasse quelques mm. Cette limite de résolution ne permet pas à l'heure actuelle de concurrencer les techniques d'imagerie médicales permettant de réaliser un examen du corps dans son intégralité (Rayons X, IRM, Scanner). Dans ce cadre, l'imagerie acousto-optique présente plusieurs avantages: elle permet de mesurer des propriétés optiques utiles pour la détection de tumeur, à la résolution spatiale des ultrasons. Cependant, les dispositifs de détection utilisés présentent un manque de sensibilité et de rapidité qui freinent le transfert de cette technique en milieu clinique.Ce constat nous a conduit à étudier les caractéristiques intrinsèques du signal acousto-optique afin de proposer deux architectures de pixels basées sur des technologies CMOS. La première architecture, totalement analogique, présente des caractéristiques de vitesse d'acquisition compatibles avec le temps de corrélation des milieux biologiques (<1 ms)et un pré-traitement du signal utile. La seconde architecture intègre une fonction de conversion analogique-numérique de manière à simplifier le montage optique, et traiter le signal plus efficacement.Par ailleurs, le contrôle de la phase en plusieurs points du front est essentiel pour refocaliser les signaux lumineux. Pour contourner les limitations de vitesse des dispositifs de contrôle adaptatif de phase de l'état de l'art, nous avons développé un dispositif monolithique constitué de l'empilement physique d'un modulateur de lumière en phase, à cristaux liquides, sur un circuit CMOS constitué d'une matrice de photo-détecteurs et de circuits de traitement afin de permettre le contrôle de front d'onde dès son acquisition. Le dispositif opto-électronique a été proposé et couplé à la première architecture électronique. Il permet de réaliser une opération sur la phase de l'onde lumineuse en chaque pixel (conjugaison de phase par ex.) en parallèle sur les pixels d'une matrice, dans un intervalle de temps inférieur au temps de corrélation des milieux biologiques
Among the optical medical imaging techniques used in medicine, the main limitation is the low resolution at a penetration depth greater than a few mm. This limitation does not allows competing with the standard imaging techniques such as X rays or RMI based imaging. In that scope, the acousto-optical imaging features several advantages: it allows measuring an optical contrast useful to detect tumors, in conjunction with the spatial resolution of ultrasound. However, the state of the art detecting devices feature a lack of sensitivity, which prevent its transfer to medical practitioners.This leads us to study the intrinsic features of the acousto-optical signal in order to propose two CMOS pixel architectures. The first one, fully analog, is compliant with the correlation time of biological tissue (1 ms typ.) and features an analog processing of the relevant signal. The second one is based on a digital pixel which contains an analog to digital converter, allowing simplifying the optical setup and increasing the robustness of the processing.In addition, related to the recent progress in wavefront control, an opto-electronic device, coupled with the first pixel architecture, has been proposed. It allows performing an optical phase operation (e.g. phase conjugation) in parallel on a pixels array, within the correlation time of biological media. Thus, this monolithic device circumvents the speed limitations of state of the art setup by a physical stacking of a liquid crystals spatial light modulator over a CMOS image sensor

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Flasseur, Olivier. "Object detection and characterization from faint signals in images : applications in astronomy and microscopy". Thesis, Lyon, 2019. http://www.theses.fr/2019LYSES042.

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La détection et la caractérisation d’objets dans des images à faible rapport signal sur bruit est un problème courant dans de nombreux domaines tels que l’astronomie ou la microscopie. En astronomie, la détection des exoplanètes et leur caractérisation par imagerie directe depuis la Terre sont des sujets de recherche très actifs. Une étoile cible et son environnement proche (abritant potentiellement des exoplanètes) sont observés sur de courtes poses. En microscopie, l’holographie en ligne est une méthode de choix pour caractériser à faibles coûts les objets microscopiques. Basée sur l’enregistrement d’un hologramme, elle permet une mise au point numérique dans n’importe quel plan du volume 3-D imagé. Dans ces deux applications cibles, le problème est rendu difficile par le faible contraste entre les objets et le fond non stationnaire des images enregistrées.Dans cette thèse, nous proposons un algorithme non-supervisé dédié à la détection et à la caractérisation d’exoplanètes par une modélisation statistique des fluctuations du fond. Cette méthode est basée sur une modélisation de la distribution statistique des données à une échelle locale de patchs, capturant ainsi leur covariances spatiales. Testé sur plusieurs jeux de données de l’imageur haut-contraste SPHERE opérant au Très Grand Télescope Européen, cet algorithme atteint de meilleures performances que les méthodes de l’état de l’art. En particulier, les cartes de détection produites sont stationnaires et statistiquement fondées. La détection des exoplanètes peut ainsi être effectuée à probabilité de fausse alarme contrôlée. L’estimation de la distribution d’énergie spectrale des sources détectées est également non biaisée. L’utilisation d’un modèle statistique permet également de déduire des précisions photométriques et astrométriques fiables. Ce cadre méthodologique est ensuite adapté pour la détection de motifs spatialement étendus tels que les motifs de diffraction rencontrés en microscopie holographique qui sont également dominés par un fond non-stationnaire. Nous proposons aussi des approches robustes basées sur des stratégies de pondération afin de réduire l’influence des nombreuses valeurs aberrantes présentes sur les données réelles. Nous montrons sur des vidéos holographiques que les méthodes de pondération proposées permettent d’atteindre un compromis biais/variance. En astronomie, la robustesse améliore les performances de détection, en particulier à courtes séparations angulaires, où les fuites stellaires dominent. Les algorithmes développés sont également adaptés pour tirer parti de la diversité spectrale des données en plus de leur diversité temporelle, améliorant ainsi leurs performances de détection et de caractérisation. Tous les algorithmes développés sont totalement non-supervisés: les paramètres de pondération et/ou de régularisation sont estimés directement à partir des données. Au-delà des applications considérées en astronomie et en microscopie, les méthodes de traitement du signal introduites dans cette thèse sont générales et pourraient être appliquées à d’autres problèmes de détection et d’estimation
Detecting and characterizing objects in images in the low signal-to-noise ratio regime is a critical issue in many areas such as astronomy or microscopy. In astronomy, the detection of exoplanets and their characterization by direct imaging from the Earth is a hot topic. A target star and its close environment (hosting potential exoplanets) are observed on short exposures. In microscopy, in-line holography is a cost-effective method for characterizing microscopic objects. Based on the recording of a hologram, it allows a digital focusing in any plane of the imaged 3-D volume. In these two fields, the object detection problem is made difficult by the low contrast between the objects and the nonstationary background of the recorded images.In this thesis, we propose an unsupervised exoplanet detection and characterization algorithm based on the statistical modeling of background fluctuations. The method, based on a modeling of the statistical distribution of patches, captures their spatial covariances. It reaches a performance superior to state-of-the-art techniques on several datasets of the European high-contrast imager SPHERE operating at the Very Large Telescope. It produces statistically grounded and spatially-stationary detection maps in which detections can be performed at a constant probability of false alarm. It also produces photometrically unbiased spectral energy distributions of the detected sources. The use of a statistical model of the data leads to reliable photometric and astrometric accuracies. This methodological framework can be adapted to the detection of spatially-extended patterns in strong structured background, such as the diffraction patterns in holographic microscopy. We also propose robust approaches based on weighting strategies to reduce the influence of the numerous outliers present in real data. We show on holographic videos that the proposed weighting approach achieves a bias/variance tradeoff. In astronomy, the robustness improves the performance of our detection method in particular at close separations where the stellar residuals dominate. Our algorithms are adapted to benefit from the possible spectral diversity of the data, which improves the detection and characterization performance. All the algorithms developed are unsupervised: weighting and/or regularization parameters are estimated in a data-driven fashion. Beyond the applications in astronomy and microscopy, the signal processing methodologies introduced are general and could be applied to other detection and estimation problems

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Rivoire, Audrey. "Contributions au guillochage et à l'authentification de photographies". Phd thesis, Université Jean Monnet - Saint-Etienne, 2012. http://tel.archives-ouvertes.fr/tel-00976616.

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L'objectif est de développer un guillochage de photographie inspiré de l'holographie numérique en ligne, capable d'encoder la signature issue d'un hachage robuste de l'image (méthode de Mihçak et Venkatesan). Une telle combinaison peut permettre l'authentification de l'image guillochée dans le domaine numérique, le cas échéant après impression. Cette approche contraint le hachage à être robuste au guillochage. La signature est codée en un nuage de formes que l'on fait virtuellement diffracter pour former la marque à insérer (guilloches dites de Fresnel) dans l'image originale. Image dense, cette marque est insérée de façon peu, voire non visible afin de ne pas gêner la perception du contenu de la photographie mais de façon à pouvoir ultérieurement lire la signature encodée en vue de la comparer à la signature de la photographie à vérifier. L'impression-lecture rend la tâche plus difficile. Le guillochage de Fresnel et l'authentification associée sont testés sur une banque (réduite) d'images

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