Image Modeling Research Papers - Academia.edu (original) (raw)

... stego data aiming at disrupting the watermark detection and of resolving copyrights, taking into account the statistics of the embedded watermark and exploiting features of the human visual system. In the second part of the paper we... more

... stego data aiming at disrupting the watermark detection and of resolving copyrights, taking into account the statistics of the embedded watermark and exploiting features of the human visual system. In the second part of the paper we propose a “second generation benchmark”. ...

Speckle is a granular noise that inherently exists in all types of coherent imaging systems. The presence of speckle in an image reduces the resolution of the image and the detectability of the target. Many speckle reduction algorithms... more

Speckle is a granular noise that inherently exists in all types of coherent imaging systems. The presence of speckle in an image reduces the resolution of the image and the detectability of the target. Many speckle reduction algorithms assume speckle noise is multiplicative. We instead model the speckle according to the exact physical process of coherent image formation. Thus, the

We consider a texture to be a stochastic, possibly periodic, two-dimensional image field. A texture model is a mathematical procedure capable of producing and describing a textured image. We explore the use of Markov random fields as... more

We consider a texture to be a stochastic, possibly periodic, two-dimensional image field. A texture model is a mathematical procedure capable of producing and describing a textured image. We explore the use of Markov random fields as texture models. The binomial model, where each point in the texture has a binomial distribution with parameter controlled by its neighbors and ``number of tries'' equal to the number of gray levels, was taken to be the basic model for the analysis. A method of generating samples from the binomial model is given, followed by a theoretical and practical analysis of the method's convergence. Examples show how the parameters of the Markov random field control the strength and direction of the clustering in the image. The power of the binomial model to produce blurry, sharp, line-like, and blob-like textures is demonstrated. Natural texture samples were digitized and their parameters were estimated under the Markov random field model. A hypothesis test was used for an objective assessment of goodness-of-fit under the Markov random field model. Overall, microtextures fit the model well. The estimated parameters of the natural textures were used as input to the generation procedure. The synthetic microtextures closely resembled their real counterparts, while the regular and inhomogeneous textures did not.

Diffraction-enhanced imaging (DEI) is an analyser-based x-ray imaging method that produces separate images depicting the projected x-ray absorption and refractive properties of an object. Because the imaging model of DEI does not account... more

Diffraction-enhanced imaging (DEI) is an analyser-based x-ray imaging method that produces separate images depicting the projected x-ray absorption and refractive properties of an object. Because the imaging model of DEI does not account for ultra-small-angle x-ray scattering (USAXS), the images produced in DEI can contain artefacts and inaccuracies in medical imaging applications. In this work, we investigate an extended DEI method for concurrent reconstruction of three images that depict an object's projected x-ray absorption, refraction and USAXS properties. The extended DEI method can be viewed as an implementation of the recently proposed multiple-image radiography paradigm. Validation studies are conducted by use of computer-simulated and synchrotron measurement data.

La modellazione per i Beni Culturali pone spesso problemi di non semplice soluzione, gestire le informazioni da dati massivi come quelli provenienti dal rilievo digitale richiede approcci specifici ed efficaci. In questo volume, redatto... more

La modellazione per i Beni Culturali pone spesso problemi di non semplice soluzione, gestire le informazioni da dati massivi come quelli provenienti dal rilievo digitale richiede approcci specifici ed efficaci. In questo volume, redatto da docenti, ricercatori e collaboratori dei corsi di Disegno Automatico e Tecniche Grafiche Avanzate, si propone un approccio efficace per il bilanciamento tra la volontà di presevare un alto livello di dettagli e la necessità di dover garantire una effettiva gestibilità dei modelli tridimensionali digitali rappresentanti architetture, archeologie ed elementi statuari e di ornato.

We propose an evolving scheme to detect slow as well as fast moving objects in a video sequence. The proposed scheme employ both spatio-temporal and temporal segmentation to obtain the video object plane and hence detection. We propose a... more

We propose an evolving scheme to detect slow as well as fast moving objects in a video sequence. The proposed scheme employ both spatio-temporal and temporal segmentation to obtain the video object plane and hence detection. We propose a compound Markov random field model as the a priori image model that takes into account the spatial distribution of the current frame, temporal frames and the edge maps of the temporal frames. The spatio-temporal segmentation is cast as a pixel labeling problem and the labels are the MAP estimates. The MAP estimates of a frame are obtained by a hybrid algorithm. The spatial segmentation of a given frame evolves to generate the spatial segmentation of the subsequent frames. The evolved spatial segmentation together with the temporal segmentation produces the Video Object Plane (VOP) and hence detection. Our scheme does require the computation of spatio-temporal segmentation of the initial frame thus speeding up the whole process. The results of the proposed scheme are compared with JSEG method are found to be better in terms of the misclassification error.

Project New technologies and reconnaissance and historical- geography and toponymy research of Toplica “land” aims to research the territory of the Toplica land, making the list of all localities dating between prehistory to the 16th... more

Project New technologies and reconnaissance and historical- geography and toponymy research of Toplica “land” aims to research the territory of the Toplica land, making the list of all localities dating between prehistory to the 16th century. Some of those are known archeological sites with material remains, and the others devastated throughout the history and witnessed today only by local tradition or toponymy. Both detailed reconnaissance and historical- geography research are conducted through extensive terrain examinations. Besides listing of localities, research team is working on gathering and sorting toponymical information. New information will profoundly extend and expand the understanding of this region. Simultaneously, new technologies used within this project would broaden the classic way of researching and thus supplement it with a new element - a possibility of making a precise map of all localities and cultural- historical monuments. All localities, known as well as unknown and undefined, will be mapped and their locations will be presented by the positions gathered from GPS. In addition, localities will be presented in a digital form through numerous photographs and films.
For the purpose of the project, two packets were tested: Photoshop and Photosynth, both on the material collected at localities of Toplica land. Testing Photoshop and Photosynth produced impression that Photoshop is more complex for using (with its numerous functions). It is good in image analysis and processing. Photosynth, on the other hand, has created very good 3D effect with its geometric topology of the pictures. Photosynth makes dynamic photos/videos, and allows exploring of places, objects, and events in detail unlike any other media; therefore, it is useful for archeological heritage, as well as all tangible (material) heritage.

With the rapid growth of video multimedia databases and the lack of textual descriptions for many of them, video annotation became a highly desired task. Conventional systems try to annotate a video query by simply finding its most... more

With the rapid growth of video multimedia databases and the lack of
textual descriptions for many of them, video annotation became a highly
desired task. Conventional systems try to annotate a video query by simply
finding its most similar videos in the database. Although the video annotation
problem has been tackled in the last decade, no attention has been paid to the
problem of assembling video keyframes in a sensed way to provide an answer
of the given video query when no single candidate video turns out to be similar
to the query. In this paper, we introduce a graph based image modeling and
indexing system for video annotation. Our system is able to improve the video
annotation task by assembling a set of graphs representing different keyframes
of different videos, to compose the video query. The experimental results
demonstrate the effectiveness of our system to annotate videos that are not
possibly annotated by classical approaches.

A promising approach for the automatic classification of normal and acute rejection transplants from Dynamic Contrast Enhanced Magnetic Resonance Imaging (DCE-MRI) is proposed. The proposed approach consists of three main steps. The first... more

A promising approach for the automatic classification of normal and acute rejection transplants from Dynamic Contrast Enhanced Magnetic Resonance Imaging (DCE-MRI) is proposed. The proposed approach consists of three main steps. The first step segments the kidney from the surrounding abdominal tissues by a level-set based deformable model with a speed function that accounts for a learned spatially variant statistical shape prior, 1st -order visual appearance descriptors of the contour interior and exterior (associated with the object and background, respectively), and a spatially invariant 2nd -order homogeneity descriptor. In the second step, to handle local object deformations due to kidney motion caused by patient breathing, we proposed a new nonrigid approach to align the object by solving Laplace’s equation between closed equispaced contours (iso-contours) of the reference and target objects. Finally, the perfusion curves that show the transportation of the contrast agent into the tissue are obtained from the segmented kidneys and used in the classification of normal and acute rejection transplants. Applications of the proposed approach yield promising results that would, in the near future, replace the use of current technologies such as nuclear imaging and ultrasonography, which are not specific enough to determine the type of kidney dysfunction.

... Samy Ait-Aoudia, Ramdane Mahiou, Elhachemi Guerrout ESI - Ecole nationale Supérieure en Informatique, BP 68M, O-Smar 16270 Algiers, Algeria s_ait_aoudia@esi.dz, r_mahiou@esi.dz, e_guerrout@esi.dz ... Potts model The Potts model is a... more

... Samy Ait-Aoudia, Ramdane Mahiou, Elhachemi Guerrout ESI - Ecole nationale Supérieure en Informatique, BP 68M, O-Smar 16270 Algiers, Algeria s_ait_aoudia@esi.dz, r_mahiou@esi.dz, e_guerrout@esi.dz ... Potts model The Potts model is a generalization of the Ising model. ...

Lithographic masks are an important and increasingly complex part of systems for advanced optical and extreme ultraviolet (EUV) lithography. They introduce polarization and phase effects with a significant impact on the entire system... more

Lithographic masks are an important and increasingly complex part of systems for advanced optical and extreme ultraviolet (EUV) lithography. They introduce polarization and phase effects with a significant impact on the entire system performance. Rigorous electromagnetic field (EMF) modeling of the mask is indispensable for a predictive simulation of lithographic processes. This paper describes several alternative mask models and their integration into a lithography simulation framework. Several examples demonstrate the relevance of an accurate mask diffraction modeling for the prediction of the lithographic process performance.