945 resultados para Video-mapping systems


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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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This thesis is focused on the study of techniques that allow to have reliable transmission of multimedia content in streaming and broadcasting applications, targeting in particular video content. The design of efficient error-control mechanisms, to enhance video transmission systems reliability, has been addressed considering cross-layer and multi-layer/multi-dimensional channel coding techniques to cope with bit errors as well as packet erasures. Mechanisms for unequal time interleaving have been designed as a viable solution to reduce the impact of errors and erasures by acting on the time diversity of the data flow, thus enhancing robustness against correlated channel impairments. In order to account for the nature of the factors which affect the physical layer channel in the evaluation of FEC schemes performances, an ad-hoc error-event modeling has been devised. In addition, the impact of error correction/protection techniques on the quality perceived by the consumers of video services applications and techniques for objective/subjective quality evaluation have been studied. The applicability and value of the proposed techniques have been tested by considering practical constraints and requirements of real system implementations.

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BACKGROUND Delayed enhancement (DE) MRI can assess the fibrotic substrate of scar-related VT. MDCT has the advantage of inframillimetric spatial resolution and better 3D reconstructions. We sought to evaluate the feasibility and usefulness of integrating merged MDCT/MRI data in 3D-mapping systems for structure-function assessment and multimodal guidance of VT mapping and ablation. METHODS Nine patients, including 3 ischemic cardiomyopathy (ICM), 3 nonischemic cardiomyopathy (NICM), 2 myocarditis, and 1 redo procedure for idiopathic VT, underwent MRI and MDCT before VT ablation. Merged MRI/MDCT data were integrated in 3D-mapping systems and registered to high-density endocardial and epicardial maps. Low-voltage areas (<1.5 mV) and local abnormal ventricular activities (LAVA) during sinus rhythm were correlated to DE at MRI, and wall-thinning (WT) at MDCT. RESULTS Endocardium and epicardium were mapped with 391 ± 388 and 1098 ± 734 points per map, respectively. Registration of MDCT allowed visualization of coronary arteries during epicardial mapping/ablation. In the idiopathic patient, integration of MRI data identified previously ablated regions. In ICM patients, both DE at MRI and WT at MDCT matched areas of low voltage (overlap 94 ± 6% and 79 ± 5%, respectively). In NICM patients, wall-thinning areas matched areas of low voltage (overlap 63 ± 21%). In patients with myocarditis, subepicardial DE matched areas of epicardial low voltage (overlap 92 ± 12%). A total number of 266 LAVA sites were found in 7/9 patients. All LAVA sites were associated to structural substrate at imaging (90% inside, 100% within 18 mm). CONCLUSION The integration of merged MDCT and DEMRI data is feasible and allows combining substrate assessment with high-spatial resolution to better define structure-function relationship in scar-related VT.

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Antiarrhythmic drugs are used in at least 50% of patients who received an implantable cardioverter defibrillator (ICD). The potential indications for antiarrhythmic drug treatments in patients with an ICD are generally the following: reduction of the number of ventricular tachycardias (VTs) or episodes of ventricular fibrillation and therefore reduction of the number of ICD therapies, most importantly, the number of disabling ICD shocks. Accordingly, the quality of life should be improved and the battery life of the ICD extended. Moreover, antiarrhythmic drugs have the potential to increase the tachycardia cycle length to allow termination of VTs by antitachycardia pacing and reduction of the number of syncopes. In addition, supraventricular arrhythmias can be prevented or their rate controlled. Recently published or reported trials have shown the efficacy of amiodarone, sotalol and azimilide to significantly reduce the number of appropriate and inappropriate ICD shocks in patients with structural heart disease. However, the use of antiarrhythmic drugs may also have adverse effects: an increase in the defibrillation threshold, an excessive increase in the VT cycle length leading to detection failure. In this situation and when antiarrhythmic drugs are ineffective or have to be stopped because of serious side effects, catheter ablation of both monomorphic stable and pleomorphic and/or unstable VTs using modern electroanatomic mapping systems should be considered. The choice of antiarrhythmic drug treatment and the need for catheter ablation in ICD patients with frequent VTs should be individually tailored to specific clinical and electrophysiological features including the frequency, the rate, and the clinical presentation of the ventricular arrhythmia. Although VT mapping and ablation is becoming increasingly practical and efficacious, ablation of VT is mostly done as an adjunctive therapy in patients with structural heart disease and ICD experiencing multiple shocks, because the recurrence and especially the occurrence of "new" VTs after primarily successful ablation with time and disease progression have precluded a widespread use of catheter ablation as primary treatment.

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Speed enforcement on public roadways is an important issue in order to guarantee road security and to reduce the number and seriousness of traffic accidents. Traditionally, this task has been partially solved using radar and/or laser technologies and, more recently, using video-camera based systems. All these systems have significant shortcomings that have yet to be overcome. The main drawback of classical Doppler radar technology is that the velocity measurement fails when several vehicles are in the radars beam. Modern radar systems are able to measure speed and range between vehicle and radar. However, this is not enough to discriminate the lane where the vehicle is driving on. The limitation of several vehicles in the beam is overcome using laser technology. However, laser systems have another important limitation: They cannot measure the speed of several vehicles simultaneously. Novel video-camera systems, based on license plate identification, solve the previous drawbacks, but they have the problem that they can only measure average speed but never top-speed. This paper studies the feasibility of using an interferometric linear frequency modulated continuous wave radar to improve top-speed enforcement on roadways. Two different systems based on down-the-road and across-the-road radar configurations are presented. The main advantage of the proposed solutions is they can simultaneously measure speed, range, and lane of several vehicles, allowing the univocal identification of the offenders. A detailed analysis about the operation and accuracy of these solutions is reported. In addition, the feasibility of the proposed techniques has been demonstrated with simulations and real experiments using a Ka-band interferometric radar developed by our research group.

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En este Proyecto de fin de carrera titulado: LA VÍDEOVIGILANCIA: TECNOLOGÍAS ACTUALES Y ASPECTOS SOCIOPOLÍTICOS, tiene como objetivo hacer un estudio en los sistemas de Vídeovigilancia basado en cámaras-IP, con fines de seguridad, control o supervisión. Nos basaremos en exponer los sistemas Vídeovigilancia basados en cámara-IP actuales de ultima generación, cuya principal virtud de estos sistemas, es la comunicación con otros lugares, o espacios públicos como privados y poder visualizar tanto en vivo como en diferido lo que este pasando en ese lugar y en ese momento o haya pasado a través del protocolo de comunicación-IP. Se explicara desde el más básico al más complejo sistema de videovigilancia-IP, también explicaremos su puesta en practica mediante los múltiples interconexiones que estos conlleven. Llegando a este punto, se nos plantea las siguientes cuestiones que da origen a este PFC. Estos sistemas de Vídeovigilancia-IP, captan las imágenes por medio de las cámaras-IP, proporcionando su facilidad tanto de visionado/grabacion, como de control, ya que no es necesario estar presente e interactuando con otros sistemas digitales de diverso índole actuales, gracias al protocolo-IP. Estos sistemas-IP, tienen su puesta en práctica mediante las instalaciones requeridas ,estas podrán ser sencillas o muy complejas de todos los sistemas-IP. Debido al gran aumento masivo, las tecnologías actuales de diverso índole de cámaras-IP en materia de la vídeovigilancia en lugares públicos, y privados en nuestra sociedad actual, lo hace un medio particularmente invasivo y por ello resulta necesario tanto la concurrencia de condiciones que legitimen los tratamientos de datos de personas identificables, como la definición de los principios y garantías que deban aplicarse ya que estas, repercutirán sobre los derechos de las personas, lo que obligara a fijar ciertas garantías. Se nos plantea los casos en los que la captación y/o tratamiento de imágenes con fines de Vídeovigilancia que pertenezcan a personas identificadas o identificables, ha obligado a España, y según dispuesto por la Directiva 95/46/CE del Parlamento Europeo, a regularizar esta situación mediante la Ley Orgánica de Protección de Datos (LOPD) 15/1999 de 13 de diciembre, bajo los procedimientos del Estado español en materia sociopolítica, y dando vigor a esta ley, mediante la aprobación de la Instrucción 1/2006 de 8 de noviembre de 2006, cuyo máximo organismo es la Agencia española de Protección de Datos (AGPD). Una vez planteada la motivación y justificación del proyecto, se derivan unos objetivos a cumplir con la realización del mismo. Los objetivos del proyecto se pueden diferenciar en dos clases principalmente. Los objetivos principales y objetivos secundarios. Los objetivos principales de este PFC, nacen directamente de las necesidades planteadas originalmente en materia de Vídeovigilancia, tanto tecnológicamente basado en las cámaras-IP en la captación y/o tratamiento de imágenes, así como sociopolíticamente donde trataremos de describirlo mediante las indicaciones y criterios con casos prácticos y de cómo deben de aplicarse según la instrucción 1/2006 mediante la LOPD en materia de Vídeovigilancia, en cuanto a la protección de datos que puedan repercutir sobre el derecho de las personas. Por otra parte los objetivos secundarios, son la extensión del objetivo primario y son de orden cuantificador en este PFC, dando una explicación más exhaustiva del objetivo principal. ABSTRACT In this final year project, entitled: THE VIDEOSURVEILLANCE: CURRENT TECHNOLOGIES AND POLITICALSOCIALS ASPECTS, aims to make a study of video surveillance systems based on IP cameras, for security, control or supervision. We will rely on to expose the camera based video surveillance systems IP-current last generation, whose main virtue of these systems, is communication with other places, or public and private spaces and to view both live and time so this happening in that place and at that time or passed through-IP communication protocol. He explained from the most basic to the most complex-IP video surveillance system, also explain its implementation into practice through multiple interconnections that these entail. Arriving at this point, we face the following issues which gave rise to this PFC. These IP-video surveillance systems, captured images through IP-cameras, providing both ease of viewing / recording, as a control, since it is not necessary to be present and interacting with other digital systems such diverse today, thanks IP-protocol. These systems-IP, have their implementation through the facilities required, these can be simple or very complex all-IP video surveillance systems. Due to the large increase in mass, current technologies of different kinds of IP cameras for video surveillance in public places, and private in our society, it makes a particularly invasive and therefore attendance is necessary both conditions that legitimize data processing of identifiable people, as the definition of the principles and safeguards to be applied as these will impact on the rights of the people, which forced to set certain guarantees. We face those cases in which the uptake and / or image processing video surveillance purposes belonging to identified or identifiable, has forced Spain, and as required by Directive 95/46/EC of the European Parliament, to regularize this situation by the Organic Law on Data Protection (LOPD) 15/1999 of December 13, under the procedures of the Spanish State in sociopolitical, and giving effect to this Act, with the approval of the Instruction 1/2006 of 8 November 2006, the governing body is the Spanish Agency for Data Protection (AGPD). Once raised the motivation and justification for the project, resulting in meeting targets to achieve the same. Project objectives can be differentiated into two main classes, the main objectives and secondary objectives: The main objectives of this PFC, born directly from requirements originally raised for capturing both technologically imaging me and try to describe where sociopolitically, the details and criteria as case studies and should be applied according to the instruction 1 / 2006 by the LOPD on video surveillance system in terms of data protection that could impact on the right people. Moreover the secondary objectives are the extension of the primary and are of a quantifier in this PFC, giving a fuller explanation of the main objective.

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We present a framework for the analysis of the decoding delay and communication latency in Multiview Video Coding. The application of this framework on MVC decoders allows minimizing the overall delay in immersive video-conference systems.

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El estudio de la distancia de visibilidad disponible en carreteras es de gran importancia para la seguridad vial. Los Mobile Mapping Systems (MMS) permiten capturar los elementos de las carreteras existentes y su entorno con alta resolución y rendimiento, obteniendo nubes de puntos 3D (LIDAR) con precisión centimétrica y fotografías panorámicas. El tratamiento de la ingente cantidad de datos que estos equipos proporcionan se ha efectuado con herramientas específicas de tratamiento de datos LIDAR y de ESRI. El cálculo de la distancia de visibilidad disponible se ha realizado mediante una aplicación que funciona sobre ArcGIS. Todo ello permite estimar la distancia de visibilidad disponible con gran precisión, utilizando tanto modelos digitales del terreno como de superficie, de manera que es posible analizar la influencia que tienen la vegetación y otros elementos de las márgenes. Se describen las técnicas utilizadas y su aplicación práctica a una carretera de la Comunidad de Madrid.

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HEVC es el nuevo estándar de codificación de vídeo que está siendo desarrollado conjuntamente por las organizaciones ITU-T Video Coding Experts Group (VCEG) e ISO/IEC Moving Picture Experts Group (MPEG). Su objetivo principal es mejorar la compresión de vídeo, en relación a los actuales estándares. Es común hoy en día, debido a su flexibilidad para aplicaciones de bajo consumo, diseñar sistemas de descodificación de vídeo basados en un procesador digital de señal (DSP). En la mayoría de las veces, los diseños parten de un código creado para ser ejecutado en un ordenador personal y posteriormente se optimizan para tecnología DSP. El objetivo principal de este proyecto es caracterizar el rendimiento de un sistema basado en DSP que ejecute el código de un descodificador de video HEVC. ABSTRACT. HEVC is a new video coding standard which is being developed by both ITU-T Video Coding Experts Group (VCEG) and ISO/IEC Moving Picture Experts Group (MPEG). Its main goal is to improve video compression, compared with the actual standards. It is common practice, because of the flexibility in low power applications, to design video decoding systems using digital signal processors (DSP). Most of the time, these designs start with a code suitable to be executed in personal computers and then it is optimized forDSP technology. The main goal in this final degree project is to characterize the performance of a DSP based system executing an HEVC video decoder.

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La presente tesis propone un nuevo método de cartografía de ensayos no destructivos en edificios históricos mediante el uso de técnicas basadas en SIG. Primeramente, se define el método por el cual es posible elaborar y convertir una cartografía 3D basada en nubes de puntos de un elemento arquitectónico obtenida mediante fotogrametría, en cartografía raster y vectorial, legible por los sistemas SIG mediante un sistema de coordenadas particular que referencian cada punto de la nube obtenida por fotogrametría. A esta cartografía inicial la denominaremos cartografía base. Después, se define el método por el cual los puntos donde se realiza un ensayo NDT se referencian al sistema de coordenadas del plano base, lo que permite la generación de cartografías de los ensayos referenciadas y la posibilidad de obtener sobre un mismo plano base diferentes datos de múltiples ensayos. Estas nuevas cartografías las denominaremos cartografías de datos, y se demostrará la utilidad de las mismas en el estudio del deterioro y la humedad. Se incluirá el factor tiempo en las cartografías, y se mostrará cómo este nuevo hecho posibilita el trabajo interdisciplinar en la elaboración del diagnóstico. Finalmente, se generarán nuevas cartografías inéditas hasta entonces consistentes en la combinación de diferentes cartografías de datos con la misma planimetría base. Estas nuevas cartografías, darán pie a la obtención de lo que se ha definido como mapas de isograma de humedad, mapa de isograma de salinidad, factor de humedad, factor de evaporación, factor de salinidad y factor de degradación del material. Mediante este sistema se facilitará una mejor visión del conjunto de los datos obtenidos en el estudio del edificio histórico, lo que favorecerá la correcta y rigurosa interpretación de los datos para su posterior restauración. ABSTRACT This research work proposes a new mapping method of non-destructive testing in historical buildings, by using techniques based on GIS. First of all, the method that makes it possible to produce and convert a 3D map based on cloud points from an architectural element obtained by photogrammetry, are defined, as raster and vector, legible by GIS mapping systems using a particular coordinate system that will refer each cloud point obtained by photogrammetry. This initial mapping will be named base planimetry. Afterwards, the method by which the points where the NDT test is performed are referenced to the coordinate system of the base plane , which allows the generation of maps of the referenced tests and the possibility of obtaining different data from multiple tests on the same base plane. These new maps will be named mapping data and their usefulness will be demonstrated in the deterioration and moisture study. The time factor in maps will be included, and how this new fact will enable the interdisciplinary work in the elaboration of the diagnosis will be proved. Finally, new maps (unpublished until now) will be generated by combining different mapping from the same planimetry data base. These new maps will enable us to obtain what have been called isograma moisture maps, isograma salinity- maps, humidity factor, evaporation factor, salinity factor and the material degradation factor. This system will provide a better vision of all data obtained in the study of historical buildings , and will ease the proper and rigorous data interpretation for its subsequent restoration.

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O uso de veículos aéreos não tripulados (VANTs) tem se tornado cada vez mais comum, principalmente em aplicações de uso civil. No cenário militar, o uso de VANTs tem focado o cumprimento de missões específicas que podem ser divididas em duas grandes categorias: sensoriamento remoto e transporte de material de emprego militar. Este trabalho se concentra na categoria do sensoriamento remoto. O trabalho foca a definição de um modelo e uma arquitetura de referência para o desenvolvimento de sensores inteligentes orientados a missões específicas. O principal objetivo destas missões é a geração de mapas temáticos. Neste trabalho são investigados processos e mecanismos que possibilitem a geração desta categoria de mapas. Neste sentido, o conceito de MOSA (Mission Oriented Sensor Array) é proposto e modelado. Como estudos de caso dos conceitos apresentados são propostos dois sistemas de mapeamento automático de fontes sonoras, um para o caso civil e outro para o caso militar. Essas fontes podem ter origem no ruído gerado por grandes animais (inclusive humanos), por motores de combustão interna de veículos ou por atividade de artilharia (incluindo caçadores). Os MOSAs modelados para esta aplicação são baseados na integração de dados provenientes de um sensor de imageamento termal e uma rede de sensores acústicos em solo. A integração das informações de posicionamento providas pelos sensores utilizados, em uma base cartográfica única, é um dos aspectos importantes tratados neste trabalho. As principais contribuições do trabalho são a proposta de sistemas MOSA, incluindo conceitos, modelos, arquitetura e a implementação de referência representada pelo sistema de mapeamento automático de fontes sonoras.

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Object tracking with subpixel accuracy is of fundamental importance in many fields since it provides optimal performance at relatively low cost. Although there are many theoretical proposals that lead to resolution increments of several orders of magnitude, in practice this resolution is limited by the imaging systems. In this paper we propose and demonstrate through simple numerical models a realistic limit for subpixel accuracy. The final result is that maximum achievable resolution enhancement is connected with the dynamic range of the image, i.e., the detection limit is 1/2∧(nr.bits). The results here presented may aid in proper design of superresolution experiments in microscopy, surveillance, defense, and other fields.

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PURPOSE OF REVIEW This article summarizes current understanding of the arrhythmia substrate and effect of catheter ablation for infarct-related ventricular tachycardia, focusing on recent findings. RECENT FINDINGS Clinical studies support the use of catheter ablation earlier in the course of ischemic disease with moderate success in reducing arrhythmia recurrence and shocks from implantable defibrillators, although mortality remains unchanged. Ablation can be lifesaving for patients presenting with electrical storm. Advanced mapping systems with image integration facilitate identification of potential substrate, and several different approaches to manage hemodynamically unstable ventricular tachycardia have emerged. Novel ablation techniques that allow deeper lesion formation are in development. SUMMARY Catheter ablation is an important therapeutic option for preventing or reducing episodes of ventricular tachycardia in patients with ischemic cardiomyopathy. Present technologies allow successful ablation in the majority of patients, even when the arrhythmia is hemodynamically unstable. Failure of the procedure is often because of anatomic challenges that will hopefully be addressed with technological progress.

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Objective
Pedestrian detection under video surveillance systems has always been a hot topic in computer vision research. These systems are widely used in train stations, airports, large commercial plazas, and other public places. However, pedestrian detection remains difficult because of complex backgrounds. Given its development in recent years, the visual attention mechanism has attracted increasing attention in object detection and tracking research, and previous studies have achieved substantial progress and breakthroughs. We propose a novel pedestrian detection method based on the semantic features under the visual attention mechanism.
Method
The proposed semantic feature-based visual attention model is a spatial-temporal model that consists of two parts: the static visual attention model and the motion visual attention model. The static visual attention model in the spatial domain is constructed by combining bottom-up with top-down attention guidance. Based on the characteristics of pedestrians, the bottom-up visual attention model of Itti is improved by intensifying the orientation vectors of elementary visual features to make the visual saliency map suitable for pedestrian detection. In terms of pedestrian attributes, skin color is selected as a semantic feature for pedestrian detection. The regional and Gaussian models are adopted to construct the skin color model. Skin feature-based visual attention guidance is then proposed to complete the top-down process. The bottom-up and top-down visual attentions are linearly combined using the proper weights obtained from experiments to construct the static visual attention model in the spatial domain. The spatial-temporal visual attention model is then constructed via the motion features in the temporal domain. Based on the static visual attention model in the spatial domain, the frame difference method is combined with optical flowing to detect motion vectors. Filtering is applied to process the field of motion vectors. The saliency of motion vectors can be evaluated via motion entropy to make the selected motion feature more suitable for the spatial-temporal visual attention model.
Result
Standard datasets and practical videos are selected for the experiments. The experiments are performed on a MATLAB R2012a platform. The experimental results show that our spatial-temporal visual attention model demonstrates favorable robustness under various scenes, including indoor train station surveillance videos and outdoor scenes with swaying leaves. Our proposed model outperforms the visual attention model of Itti, the graph-based visual saliency model, the phase spectrum of quaternion Fourier transform model, and the motion channel model of Liu in terms of pedestrian detection. The proposed model achieves a 93% accuracy rate on the test video.
Conclusion
This paper proposes a novel pedestrian method based on the visual attention mechanism. A spatial-temporal visual attention model that uses low-level and semantic features is proposed to calculate the saliency map. Based on this model, the pedestrian targets can be detected through focus of attention shifts. The experimental results verify the effectiveness of the proposed attention model for detecting pedestrians.