60 research outputs found

    Improving the Performance of Single Chip Image Capture Devices

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    Single chip charge-coupled devices (CCDs) coupled with filters for isolating red, green, and blue color content are commonly used to capture color images. While this is more cost effective than multiple chip systems, best results are obtained when full RGB color information is obtained for every point in an image. The process of color subsampling in a single chip system degrades the resulting image data by introducing artifacts such as blurry edges and false coloring. We propose an algorithm for enhancing color image data that were captured with a typical single chip CCD array. The algorithm is based on stochastic regularization using a Markov random field model for the image data. This results in a constrained optimization problem, which is solved using an iterative constrained gradient descent computational algorithm. Results of the proposed algorithm show a marked improvement over the original sampled image data

    Enhancing a Neurosurgical Imaging System with a PC-based Video Processing Solution

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    This work presents a PC-based prototype video processing application developed to be used with a specific neurosurgical imaging device, the OPMI® PenteroTM operating microscope, in the Department of Neurosurgery of Helsinki University Central Hospital at Töölö, Helsinki. The motivation for implementing the software was the lack of some clinically important features in the imaging system provided by the microscope. The imaging system is used as an online diagnostic aid during surgery. The microscope has two internal video cameras; one for regular white light imaging and one for near-infrared fluorescence imaging, used for indocyanine green videoangiography. The footage of the microscope’s current imaging mode is accessed via the composite auxiliary output of the device. The microscope also has an external high resolution white light video camera, accessed via a composite output of a separate video hub. The PC was chosen as the video processing platform for its unparalleled combination of prototyping and high-throughput video processing capabilities. A thorough analysis of the platform and efficient video processing methods was conducted in the thesis and the results were used in the design of the imaging station. The features found feasible during the project were incorporated into a video processing application running on a GNU/Linux distribution Ubuntu. The clinical usefulness of the implemented features was ensured beforehand by consulting the neurosurgeons using the original system. The most significant shortcomings of the original imaging system were mended in this work. The key features of the developed application include: live streaming, simultaneous streaming and recording, and playing back of upto two video streams. The playback mode provides full media player controls, with a frame-by-frame precision rewinding, in an intuitive and responsive interface. A single view and a side-by-side comparison mode are provided for the streams. The former gives more detail, while the latter can be used, for example, for before-after and anatomic-angiographic comparisons.fi=Opinnäytetyö kokotekstinä PDF-muodossa.|en=Thesis fulltext in PDF format.|sv=Lärdomsprov tillgängligt som fulltext i PDF-format

    Energy-Efficient Computing for Mobile Signal Processing

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    Mobile devices have rapidly proliferated, and deployment of handheld devices continues to increase at a spectacular rate. As today's devices not only support advanced signal processing of wireless communication data but also provide rich sets of applications, contemporary mobile computing requires both demanding computation and efficiency. Most mobile processors combine general-purpose processors, digital signal processors, and hardwired application-specific integrated circuits to satisfy their high-performance and low-power requirements. However, such a heterogeneous platform is inefficient in area, power and programmability. Improving the efficiency of programmable mobile systems is a critical challenge and an active area of computer systems research. SIMD (single instruction multiple data) architectures are very effective for data-level-parallelism intense algorithms in mobile signal processing. However, new characteristics of advanced wireless/multimedia algorithms require architectural re-evaluation to achieve better energy efficiency. Therefore, fourth generation wireless protocol and high definition mobile video algorithms are analyzed to enhance a wide-SIMD architecture. The key enhancements include 1) programmable crossbar to support complex data alignment, 2) SIMD partitioning to support fine-grain SIMD computation, and 3) fused operation to support accelerating frequently used instruction pairs. Near-threshold computation has been attractive in low-power architecture research because it balances performance and power. To further improve energy efficiency in mobile computing, near-threshold computation is applied to a wide SIMD architecture. This proposed near-threshold wide SIMD architecture-Diet SODA-presents interesting architectural design decisions such as 1) very wide SIMD datapath to compensate for degraded performance induced by near-threshold computation and 2) scatter-gather data prefetcher to exploit large latency gap between memory and the SIMD datapath. Although near-threshold computation provides excellent energy efficiency, it suffers from increased delay variations. A systematic study of delay variations in near-threshold computing is performed and simple techniques-structural duplication and voltage/frequency margining-are explored to tolerate and mitigate the delay variations in near-threshold wide SIMD architectures. This dissertation analyzes representative wireless/multimedia mobile signal processing algorithms, proposes an energy-efficient programmable platform, and evaluates performance and power. A main theme of this dissertation is that the performance and efficiency of programmable embedded systems can be significantly improved with a combination of parallel SIMD and near-threshold computations.Ph.D.Electrical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/86356/1/swseo_1.pd

    Flexible Hardware Architectures for Retinal Image Analysis

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    RÉSUMÉ Des millions de personnes autour du monde sont touchées par le diabète. Plusieurs complications oculaires telle que la rétinopathie diabétique sont causées par le diabète, ce qui peut conduire à une perte de vision irréversible ou même la cécité si elles ne sont pas traitées. Des examens oculaires complets et réguliers par les ophtalmologues sont nécessaires pour une détection précoce des maladies et pour permettre leur traitement. Comme solution préventive, un protocole de dépistage impliquant l'utilisation d'images numériques du fond de l'œil a été adopté. Cela permet aux ophtalmologistes de surveiller les changements sur la rétine pour détecter toute présence d'une maladie oculaire. Cette solution a permis d'obtenir des examens réguliers, même pour les populations des régions éloignées et défavorisées. Avec la grande quantité d'images rétiniennes obtenues, des techniques automatisées pour les traiter sont devenues indispensables. Les techniques automatisées de détection des maladies des yeux ont été largement abordées par la communauté scientifique. Les techniques développées ont atteint un haut niveau de maturité, ce qui a permis entre autre le déploiement de solutions en télémédecine. Dans cette thèse, nous abordons le problème du traitement de volumes élevés d'images rétiniennes dans un temps raisonnable dans un contexte de dépistage en télémédecine. Ceci est requis pour permettre l'utilisation pratique des techniques développées dans le contexte clinique. Dans cette thèse, nous nous concentrons sur deux étapes du pipeline de traitement des images rétiniennes. La première étape est l'évaluation de la qualité de l'image rétinienne. La deuxième étape est la segmentation des vaisseaux sanguins rétiniens. L’évaluation de la qualité des images rétinienne après acquisition est une tâche primordiale au bon fonctionnement de tout système de traitement automatique des images de la rétine. Le rôle de cette étape est de classifier les images acquises selon leurs qualités, et demander une nouvelle acquisition en cas d’image de mauvaise qualité. Plusieurs algorithmes pour évaluer la qualité des images rétiniennes ont été proposés dans la littérature. Cependant, même si l'accélération de cette tâche est requise en particulier pour permettre la création de systèmes mobiles de capture d'images rétiniennes, ce sujet n'a pas encore été abordé dans la littérature. Dans cette thèse, nous ciblons un algorithme qui calcule les caractéristiques des images pour permettre leur classification en mauvaise, moyenne ou bonne qualité. Nous avons identifié le calcul des caractéristiques de l'image comme une tâche répétitive qui nécessite une accélération. Nous nous sommes intéressés plus particulièrement à l’accélération de l’algorithme d’encodage à longueur de séquence (Run-Length Matrix – RLM). Nous avons proposé une première implémentation complètement logicielle mise en œuvre sous forme d’un système embarqué basé sur la technologie Zynq de Xilinx. Pour accélérer le calcul des caractéristiques, nous avons conçu un co-processeur capable de calculer les caractéristiques en parallèle implémenté sur la logique programmable du FPGA Zynq. Nous avons obtenu une accélération de 30,1 × pour la tâche de calcul des caractéristiques de l’algorithme RLM par rapport à son implémentation logicielle sur la plateforme Zynq. La segmentation des vaisseaux sanguins rétiniens est une tâche clé dans le pipeline du traitement des images de la rétine. Les vaisseaux sanguins et leurs caractéristiques sont de bons indicateurs de la santé de la rétine. En outre, leur segmentation peut également aider à segmenter les lésions rouges, indicatrices de la rétinopathie diabétique. Plusieurs techniques de segmentation des vaisseaux sanguins rétiniens ont été proposées dans la littérature. Des architectures matérielles ont également été proposées pour accélérer certaines de ces techniques. Les architectures existantes manquent de performances et de flexibilité de programmation, notamment pour les images de haute résolution. Dans cette thèse, nous nous sommes intéressés à deux techniques de segmentation du réseau vasculaire rétinien, la technique du filtrage adapté et la technique des opérateurs de ligne. La technique de filtrage adapté a été ciblée principalement en raison de sa popularité. Pour cette technique, nous avons proposé deux architectures différentes, une architecture matérielle personnalisée mise en œuvre sur FPGA et une architecture basée sur un ASIP. L'architecture matérielle personnalisée a été optimisée en termes de surface et de débit de traitement pour obtenir des performances supérieures par rapport aux implémentations existantes dans la littérature. Cette implémentation est plus efficace que toutes les implémentations existantes en termes de débit. Pour l'architecture basée sur un processeur à jeu d’instructions spécialisé (Application-Specific Instruction-set Processor – ASIP), nous avons identifié deux goulets d'étranglement liés à l'accès aux données et à la complexité des calculs de l'algorithme. Nous avons conçu des instructions spécifiques ajoutées au chemin de données du processeur. L'ASIP a été rendu 7.7 × plus rapide par rapport à son architecture de base. La deuxième technique pour la segmentation des vaisseaux sanguins est l'algorithme détecteur de ligne multi-échelle (Multi-Scale Ligne Detector – MSLD). L'algorithme MSLD est choisi en raison de ses performances et de son potentiel à détecter les petits vaisseaux sanguins. Cependant, l'algorithme fonctionne en multi-échelle, ce qui rend l’algorithme gourmand en mémoire. Pour résoudre ce problème et permettre l'accélération de son exécution, nous avons proposé un algorithme efficace en terme de mémoire, conçu et implémenté sur FPGA. L'architecture proposée a réduit de façon drastique les exigences de l’algorithme en terme de mémoire en réutilisant les calculs et la co-conception logicielle/matérielle. Les deux architectures matérielles proposées pour la segmentation du réseau vasculaire rétinien ont été rendues flexibles pour pouvoir traiter des images de basse et de haute résolution. Ceci a été réalisé par le développement d'un compilateur spécifique capable de générer une description HDL de bas niveau de l'algorithme à partir d'un ensemble de paramètres. Le compilateur nous a permis d’optimiser les performances et le temps de développement. Dans cette thèse, nous avons introduit deux architectures qui sont, au meilleur de nos connaissances, les seules capables de traiter des images à la fois de basse et de haute résolution.----------ABSTRACT Millions of people all around the world are affected by diabetes. Several ocular complications such as diabetic retinopathy are caused by diabetes, which can lead to irreversible vision loss or even blindness if not treated. Regular comprehensive eye exams by eye doctors are required to detect the diseases at earlier stages and permit their treatment. As a preventing solution, a screening protocol involving the use of digital fundus images was adopted. This allows eye doctors to monitor changes in the retina to detect any presence of eye disease. This solution made regular examinations widely available, even to populations in remote and underserved areas. With the resulting large amount of retinal images, automated techniques to process them are required. Automated eye detection techniques are largely addressed by the research community, and now they reached a high level of maturity, which allows the deployment of telemedicine solutions. In this thesis, we are addressing the problem of processing a high volume of retinal images in a reasonable time. This is mandatory to allow the practical use of the developed techniques in a clinical context. In this thesis, we focus on two steps of the retinal image pipeline. The first step is the retinal image quality assessment. The second step is the retinal blood vessel segmentation. The evaluation of the quality of the retinal images after acquisition is a primary task for the proper functioning of any automated retinal image processing system. The role of this step is to classify the acquired images according to their quality, which will allow an automated system to request a new acquisition in case of poor quality image. Several algorithms to evaluate the quality of retinal images were proposed in the literature. However, even if the acceleration of this task is required, especially to allow the creation of mobile systems for capturing retinal images, this task has not yet been addressed in the literature. In this thesis, we target an algorithm that computes image features to allow their classification to bad, medium or good quality. We identified the computation of image features as a repetitive task that necessitates acceleration. We were particularly interested in accelerating the Run-Length Matrix (RLM) algorithm. We proposed a first fully software implementation in the form of an embedded system based on Xilinx's Zynq technology. To accelerate the features computation, we designed a co-processor able to compute the features in parallel, implemented on the programmable logic of the Zynq FPGA. We achieved an acceleration of 30.1× over its software implementation for the features computation part of the RLM algorithm. Retinal blood vessel segmentation is a key task in the pipeline of retinal image processing. Blood vessels and their characteristics are good indicators of retina health. In addition, their segmentation can also help to segment the red lesions, indicators of diabetic retinopathy. Several techniques have been proposed in the literature to segment retinal blood vessels. Hardware architectures have also been proposed to accelerate blood vessel segmentation. The existing architectures lack in terms of performance and programming flexibility, especially for high resolution images. In this thesis, we targeted two techniques, matched filtering and line operators. The matched filtering technique was targeted mainly because of its popularity. For this technique, we proposed two different architectures, a custom hardware architecture implemented on FPGA, and an Application Specific Instruction-set Processor (ASIP) based architecture. The custom hardware architecture area and timing were optimized to achieve higher performances in comparison to existing implementations. Our custom hardware implementation outperforms all existing implementations in terms of throughput. For the ASIP based architecture, we identified two bottlenecks related to data access and computation intensity of the algorithm. We designed two specific instructions added to the processor datapath. The ASIP was made 7.7× more efficient in terms of execution time compared to its basic architecture. The second technique for blood vessel segmentation is the Multi-Scale Line Detector (MSLD) algorithm. The MSLD algorithm is selected because of its performance and its potential to detect small blood vessels. However, the algorithm works at multiple scales which makes it memory intensive. To solve this problem and allow the acceleration of its execution, we proposed a memory-efficient algorithm designed and implemented on FPGA. The proposed architecture reduces drastically the memory requirements of the algorithm by reusing the computations and SW/HW co-design. The two hardware architectures proposed for retinal blood vessel segmentation were made flexible to be able to process low and high resolution images. This was achieved by the development of a specific compiler able to generate low-level HDL descriptions of the algorithm from a set of the algorithm parameters. The compiler enabled us to optimize performance and development time. In this thesis, we introduce two novel architectures which are, to the best of our knowledge, the only ones able to process both low and high resolution images

    Image-based Control and Automation of High-speed X-ray Imaging Experiments

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    Moderne Röntgenbildgebung gibt Aufschluss über die innere Struktur von Objekten aus den verschiedensten Materialien. Der Erfolg solcher Messungen hängt dabei entscheidend von einer geeigneten Wahl der Aufnahmebedingungen ab, von der mechanischen Instrumentierung und von den Eigenschaften der Probe oder des untersuchten Prozesses selbst. Bisher gibt es kein bekanntes Verfahren für autonome Datenakquise, welches auch für sehr verschiedene Röntgenbildgebungsexperimenten die Steuerung über bildbasiertes Feedback erlaubt. Die vorliegende Arbeit setzt sich als Ziel, diese Lücke zu schließen, indem gezielt die hierbei auftretenden Probleme angegangen und gelöst werden: die Auswahl der experimentellen Startparameter, eine schnelle Verarbeitung der aufgenommenen Daten und ein automatisches Feedback zur Korrektur der laufenden Messprozedur. Um die am besten geeigneten experimentellen Bedingungen zu bestimmen, gehen wir von den Grundlagen der Bildentstehung aus und entwickeln ein Framework für dessen Simulation. Dieses ermöglicht uns eine große Bandbreite an virtuellen Röntgenbildgebungsexperimenten durchzuführen, wobei die entscheidenden physikalischen Prozesse auf dem Weg der Röntgenstrahlung von der Quelle bis zum Detektor berücksichtigt werden. Darüber hinaus betrachten wir verschiedene Probenformen und bewegungen, was uns die Simulation von Experimenten wie etwa 4D (zeitaufgelöster) Tomographie ermöglicht. Außerdem entwickeln wir eine autonome Prozedur für die Datenakquise, welches die Startbedingungen des Versuchs dann während der schon laufenden Messung auf Basis schneller Bildanalyse das nachjustiert und auch andere Parameter des Experiments steuern kann. Besonderes Augenmerk legen wir hier auf Hochgeschwindigkeitsexperimente, welche hohen Anforderungen an die Geschwindigkeit der Datenverarbeitung stellen, vor allem wenn die Steuerung auf rechenintensiven Algorithmen wie etwa für die tomographische 3D Rekonstruktion der Probe basiert. Um hierzu einen effizienten Algorithmus zu implementieren, verwenden wir ein hochgradig parallelisiertes Framework. Dessen Ausgabe kann dann zur Berechnung verschiedener Bildmetriken verwendet werden, um quantitative Information über die aufgenommenen Daten zu erhalten. Diese bilden die Grundlage zur Entscheidungsfindung in einem geschlossenen Regelkreis, in dem die Hardware für die Datenakquise betrieben wird. Die Genauigkeit des entwickelten Simulationsframeworks zeigen wir, indem wir virtuelle und reale Experimente vergleichen, die auf Gitterinterferometrie basieren und damit spezielle optische Elemente für die Kontrastbildung einsetzen. Außerdem untersuchen wir im Detail den Einfluss der Bildgebungsbedingungen auf die Genauigkeit des implementierten Algorithmus für gefilterte Rückprojektion, und inwiefern unter dessen Berücksichtigung eine Optimierung der experimentellen Bedingungen möglich ist. Wir demonstrieren die Fähigkeiten des von uns entwickelten Systems zur autonomen Datenakquise anhand eines in-situ Tomographieexperiments, bei dem es basierend auf 3D-Rekonstruktion die Framerate der Kamera optimiert und damit sicherstellt, dass die aufgezeichneten Datensätze ohne Artefakte rekonstruiert werden können. Außerdem nutzen wir unser System, um ein Tomographieexperiment mit hohem Probendurchsatz durchzuführen, bei dem viele ähnliche biologische Proben gescannt werde: Für jede davon wird automatisch die tomographische Rotationsachse bestimmt und schließlich zur Sicherstellung der Qualität schon während der Messung ein komplettes 3D Volumen rekonstruiert. Darüber hinaus führen wir ein in-situ Laminographieexperiment durch, welches die Rissbildung in einer Materialprobe untersucht. Hierbei führt unser System die Datenakquise durch und rekonstruiert einen zentral gelegenen Querschnitt durch die Probe, um dessen korrekte Ausrichtung und die Qualität der Daten sicherzustellen. Unsere Arbeit ermöglicht - basierend auf hochgenauen Simulationen - die Wahl der am besten geeigneten Startbedingungen eines Experiments, deren Feinabstimmung während eines realen Experiments und schließlich dessen automatische Steuerung basierend auf schneller Analyse der gerade aufgezeichneten Daten. Ein solches Vorgehen bei der Datenakquise ermöglicht neuartige in-vivo und in-situ Hochgeschwindigkeitsexperimente, die bedingt durch die hohen Datenraten nicht mehr von einer menschlichen Bedienperson gehandhabt werden könnten

    Towards the development of flexible, reliable, reconfigurable, and high-performance imaging systems

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    Current FPGAs can implement large systems because of the high density of reconfigurable logic resources in a single chip. FPGAs are comprehensive devices that combine flexibility and high performance in the same platform compared to other platform such as General-Purpose Processors (GPPs) and Application Specific Integrated Circuits (ASICs). The flexibility of modern FPGAs is further enhanced by introducing Dynamic Partial Reconfiguration (DPR) feature, which allows for changing the functionality of part of the system while other parts are functioning. FPGAs became an important platform for digital image processing applications because of the aforementioned features. They can fulfil the need of efficient and flexible platforms that execute imaging tasks efficiently as well as the reliably with low power, high performance and high flexibility. The use of FPGAs as accelerators for image processing outperforms most of the current solutions. Current FPGA solutions can to load part of the imaging application that needs high computational power on dedicated reconfigurable hardware accelerators while other parts are working on the traditional solution to increase the system performance. Moreover, the use of the DPR feature enhances the flexibility of image processing further by swapping accelerators in and out at run-time. The use of fault mitigation techniques in FPGAs enables imaging applications to operate in harsh environments following the fact that FPGAs are sensitive to radiation and extreme conditions. The aim of this thesis is to present a platform for efficient implementations of imaging tasks. The research uses FPGAs as the key component of this platform and uses the concept of DPR to increase the performance, flexibility, to reduce the power dissipation and to expand the cycle of possible imaging applications. In this context, it proposes the use of FPGAs to accelerate the Image Processing Pipeline (IPP) stages, the core part of most imaging devices. The thesis has a number of novel concepts. The first novel concept is the use of FPGA hardware environment and DPR feature to increase the parallelism and achieve high flexibility. The concept also increases the performance and reduces the power consumption and area utilisation. Based on this concept, the following implementations are presented in this thesis: An implementation of Adams Hamilton Demosaicing algorithm for camera colour interpolation, which exploits the FPGA parallelism to outperform other equivalents. In addition, an implementation of Automatic White Balance (AWB), another IPP stage that employs DPR feature to prove the mentioned novelty aspects. Another novel concept in this thesis is presented in chapter 6, which uses DPR feature to develop a novel flexible imaging system that requires less logic and can be implemented in small FPGAs. The system can be employed as a template for any imaging application with no limitation. Moreover, discussed in this thesis is a novel reliable version of the imaging system that adopts novel techniques including scrubbing, Built-In Self Test (BIST), and Triple Modular Redundancy (TMR) to detect and correct errors using the Internal Configuration Access Port (ICAP) primitive. These techniques exploit the datapath-based nature of the implemented imaging system to improve the system's overall reliability. The thesis presents a proposal for integrating the imaging system with the Robust Reliable Reconfigurable Real-Time Heterogeneous Operating System (R4THOS) to get the best out of the system. The proposal shows the suitability of the proposed DPR imaging system to be used as part of the core system of autonomous cars because of its unbounded flexibility. These novel works are presented in a number of publications as shown in section 1.3 later in this thesis

    Diseño CMOS de un sistema de visión “on-chip” para aplicaciones de muy alta velocidad

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    Falta palabras claveEsta Tesis presenta arquitecturas, circuitos y chips para el diseño de sensores de visión CMOS con procesamiento paralelo embebido. La Tesis reporta dos chips, en concreto: El chip Q-Eye; El chip Eye-RIS_VSoC.. Y dos sistemas de visión construidos con estos chips y otros sistemas “off-chip” adicionales, como FPGAs, en concreto: El sistema Eye-RIS_v1; El sistema Eye-RIS_v2. Estos chips y sistemas están concebidos para ejecutar tareas de visión a muy alta velocidad y con consumos de potencia moderados. Los sistemas resultantes son, además, compactos y por lo tanto ventajosos en términos del factor SWaP cuando se los compara con arquitecturas convencionales formadas por sensores de imágenes convencionales seguidos de procesadores digitales. La clave de estas ventajas en términos de SWaP y velocidad radica en el uso de sensores-procesadores, en lugar de meros sensores, en la interface de los sistemas de visión. Estos sensores-procesadores embeben procesadores programables de señal-mixta dentro del pixel y son capaces tanto de adquirir imágenes como de pre-procesarlas para extraer características, eliminar información redundante y reducir el número de datos que se transmiten fuera del sensor para su procesamiento ulterior. El núcleo de la tesis es el sensor-procesador Q-Eye, que se usa como interface en los sistemas Eye-RIS. Este sensor-procesador embebe una arquitectura de procesamiento formada por procesadores de señal-mixta distribuidos por pixel. Sus píxeles son por tanto estructuras multi-funcionales complejas. De hecho, son programables, incorporan memorias e interactúan con sus vecinos para realizar una variedad de operaciones, tales como: Convoluciones lineales con máscaras programables; Difusiones controladas por tiempo y nivel de señal, a través de un “grid” resistivo embebido en el plano focal; Aritmética de imágenes; Flujo de programación dependiente de la señal; Conversión entre los dominios de datos: imagen en escala de grises e imagen binaria; Operaciones lógicas en imágenes binarias; Operaciones morfológicas en imágenes binarias. etc. Con respecto a otros píxeles multi-función y sensores-procesadores anteriores, el Q-Eye reporta entre otras las siguientes ventajas: Mayor calidad de la imagen y mejores prestaciones de las funcionalidades embebidas en el chip; Mayor velocidad de operación y mejor gestión de la energía disponible; Mayor versatilidad para integración en sistemas de visión industrial. De hecho, los sistemas Eye-RIS son los primeros sistemas de visión industriales dotados de las siguientes características: Procesamiento paralelo distribuido y progresivo; Procesadores de señal-mixta fiables, robustos y con errores controlados; Programabilidad distribuida. La Tesis incluye descripciones detalladas de la arquitectura y los circuitos usados en el pixel del Q-Eye, del propio chip Q-Eye y de los sistemas de visión construidos en base a este chip. Se incluyen también ejemplos de los distintos chips en operaciónThis Thesis presents architectures, circuits and chips for the implementation of CMOS VISION SENSORS with embedded parallel processing. The Thesis reports two chips, namely: Q-eye chip; Eye-RIS_VSoC chip, and two vision systems realized by using these chips and some additional “off-chip” circuitry, such as FPGAs. These vision systems are: Eye-RIS_v1 system; Eye-RIS_v2 system. The chips and systems reported in the Thesis are conceived to perform vision tasks at very high speed and with moderate power consumption. The proposed vision systems are also compact and advantageous in terms of SWaP factors as compared with conventional architectures consisting of standard image sensor followed by digital processors. The key of these advantages in terms of SWaP and speed lies in the use of sensors-processors, rather than mere sensors, in the front-end interface of vision systems. These sensors-processors embed mixed-signal programmable processors inside the pixel. Therefore, they are able to acquire images and process them to extract the features, removing the redundant information and reducing the data throughput for later processing. The core of the Thesis is the sensor-processor Q-Eye, which is used as front-end in the Eye-RIS systems. This sensor-processor embeds a processing architecture composed by mixed-signal processors distributed per pixel. Then, its pixels are complex multi-functional structures. In fact, they are programmable, incorporate memories and interact with its neighbors in order to carry out a set of operations, including: Linear convolutions with programmable linear masks; Time- and signal-controlled diffusions (by means of an embedded resistive grid); Image arithmetic; Signal-dependent data scheduling; Gray-scale to binary transformation; Logic operation on binary images; Mathematical morphology on binary images, etc. As compared with previous multi-function pixels and sensors-processors, the Q-Eye brings among other the following advantages: Higher image quality and better performances of functionalities embedded on chip; Higher operation speed and better management of energy budget; More versatility for integration in industrial vision systems. In fact, the Eye-RIS systems are the first industrial vision systems equipped with the following characteristics: Parallel distributed and progressive processing; Reliable, robust mixed-signal processors with handled errors; Distributed programmability. This Thesis includes detailed descriptions of architecture and circuits used in the Q-Eye pixel, in the Q-Eye chip itself and in the vision systems developed based on this chip. Also, several examples of chips and systems in operation are presented

    Real-time scalable video coding for surveillance applications on embedded architectures

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    CMOS camera employing a double junction active pixel

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