High frame rate video (HFV) is an important investigational tool in sciences, engineering and military. In ultrahigh speed imaging, the obtainable temporal, spatial and spectral resolutions are limited by the sustainable throughput of in-camera mass memory, the lower bound of exposure time, and illumination conditions. In order to break these bottlenecks, we propose a new coded video acquisition framework that employs K>1 cameras, each of which makes random measurements of the video signal in both temporal and spatial domains. For each of the K cameras, this multi-camera strategy greatly relaxes the stringent requirements in memory speed, shutter speed, and illumination strength. The recovery of HFV from these random measurements is posed and solved as a large scale l1 minimization problem by exploiting joint temporal and spatial sparsities of the 3D signal. Three coded video acquisition techniques of varied trade o s between performance and hardware complexity are developed: frame-wise coded acquisition, pixel-wise coded acquisition, and column-row-wise coded acquisition. The performances of these techniques are analyzed in relation to the sparsity of the underlying video signal. To make ultra high speed cameras of coded exposure more practical and a fordable, we develop a coded exposure video/image acquisition system by an innovative assembling of multiple rolling shutter cameras. Each of the constituent rolling shutter cameras adopts a random pixel read-out mechanism by simply changing the read out order of pixel rows from sequential to random. Simulations of these new image/video coded acquisition techniques are carried out and experimental results are reported. / Dissertation / Doctor of Philosophy (PhD)

Modern automotive systems increasingly depend on camera sensors to gather safetycriticaldata used in driver-assisting features of the system. These features can consist offor example, lane-keeping assist and automatic braking where the sensors register objectswithin certain distances. When these camera sensors gather information, the time of theimage is critical for the calculation of speeds, distances, and size of any potential registeredobject in the frame. Limitations of bandwidth and computing in such vehicles creates aneed to use special cameras that do not capture the whole image simultaneously but insteadcapture the images piecewise. These cameras are called rolling shutter cameras. Thisputs pressure on defining when an image was captured when different parts of the imagewere captured at different points in time. For this thesis, this point in time is defined as thechronological middle point in between the camera starting to capture an image and when ithas collected the final part of it. This thesis performs a mapping-study to evaluate methodsto verify the timestamp of an image generated from rolling shutter cameras. Further, thisthesis proposes a new method using multiple digital clocks and presents its performanceusing a proof-of-concept implementation to prove the method’s ability to accurately representtime with sub-millisecond accuracy.

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This literary study examines the relationship between the hardboiled detective and the 2003 detective novel Shutter Island by Dennis Lehane. Known for his thought provoking stories as a crime novelist, Lehane exemplifies the desire of a current literary shift from stoic patriarchal constructs of detective archetypes towards a more feminist perspective. This thesis focuses on how Shutter Island reflects on the restrictive attributes of the hardboiled detective whilst illuminating a realist depiction of male vulnerability.              The theoretical background of this research is derived from existing feminist literary theories that observe patterns of the hardboiled detective in relation to crime literature from the 20th century to the modern day. This paper applies feminist literary theory to illustrate how traditional themes within this type of literature have shifted in favor of the emerging contemporary detective depicted in feminist crime fiction.

Cette thèse apporte des solutions théoriques et pratiques à deux problèmes soulevés par la photographie numérique en présence de mouvement, et par la photographie infrarouge. La photographie d'objets en mouvement semblait ne pouvoir se faire qu'avec des temps d'exposition très courts, jusqu'à ce que deux travaux révolutionnaires proposent deux nouveaux types de caméra permettant un temps d'exposition arbitraire. Le flutter shutter de Agrawal et al. crée en effet un flou inversible, grâce à un obturateur aux séquences d'ouverture-fermeture bie{\it n choisies. Le motion invariant photography de Levin et al. obtient ce même effet avec une accélération constante de la caméra. Les deux méthodes suivent ainsi un nouveau paradigme, la computational photography, selon lequel les caméras sont repensées, car elles incluent un traitement numérique sophistiqué. Cette thèse propose une méthode pour évaluer la qualité image des nouvelles caméras. Le fil conducteur de l'analyse est donc l'évaluation du SNR (signal to noise ratio) de l'image obtenue après déconvolution. La théorie fournit des formules explicites pour le SNR, soulève deux paradoxes de ces caméras, et les résout. Elle permet d'obtenir le modèle de mouvement sous-jacent à chaque flutter shutter, notamment tous ceux qui sont brevetés. Une seconde partie plus brève aborde le problème de qualité principal en imagerie vidéo infrarouge, la non-uniformité. Il s'agit d'un bruit évolutif et structuré en colonnes causé par le capteur. La conclusion des travaux est qu'il est non seulement possible mais également efficace et robuste d'effectuer la correction sur une seule image. Cela permet de contourner le problème récurrent des "ghost artifacts"résultant d'une incohérence du traitement par rapport au modèle d'acquisition. / This thesis provides theoretical and practical solutions to two problems raised by digital photography of moving scenes, and infrared photography. Until recently photographing moving objects could only be done using short exposure times. Yet, two recent groundbreaking works have proposed two new designs of camera allowing arbitrary exposure times. The flutter shutter of Agrawal et al. creates an invertible motion blur by using a clever shutter technique to interrupt the photon flux during the exposure time according to a well chosen binary sequence. The motion-invariant photography of Levin et al. gets the same result by accelerating the camera at a constant rate. Both methods follow computational photography as a new paradigm. The conception of cameras is rethought to include sophisticated digital processing. This thesis proposes a method for evaluating the image quality of these new cameras. The leitmotiv of the analysis is the SNR (signal to noise ratio) of the image after deconvolution. It gives the efficiency of these new camera design in terms of image quality. The theory provides explicit formulas for the SNR. It raises two paradoxes of these cameras, and resolves them. It provides the underlying motion model of each flutter shutter, including patented ones. A shorter second part addresses the the main quality problem in infrared video imaging, the non-uniformity. This perturbation is a time-dependent noise caused by the infrared sensor, structured in columns. The conclusion of this work is that it is not only possible but also efficient and robust to perform the correction on a single image. This permits to ensure the absence of ``ghost artifacts'', a classic of the literature on the subject, coming from inadequate processing relative to the acquisition model.

Global shutter pixels are indispensable for applications wherein the minimisation of motion artefacts is of critical importance. However, these pixels are more complex than the common rolling shutter type pixels and require some form of per-pixel storage. They are almost invariably reliant upon metal light shielding in order to protect their in-pixel memory nodes and this prevents them from taking advantage of some of the latest developments in CMOS image sensor technology. Backside-illumination is the most prominent example of such a technology. The greater sensitivity afforded by the reduced optical stack height is indispensable for many applications, particularly in the mobile market where form factor and power consumption are constrained. The design challenge is to exploit these advantages offered by backside-illumination without making use of metal shielding of the per-pixel memory. The research in this thesis covers the design, implementation and characterisation of a back-illuminated voltage-domain global shutter pixel. The pixel architecture is a novel 10 transistor-per-pixel architecture with dual independent in-pixel storage nodes. Beginning with the pixel architecture, the design is developed through TCAD-driven photodiode and pixel layout co-optimisation. The behaviour of pixels with differential parasitic light sensitivity (PLS) behaviour is analysed in greater detail than previously reported and a prediction model is developed based upon this. The 10T pixel is characterised and found to have excellent PLS of -73:5 dB native and -82:5 dB differential PLS at 940 nm. The dual in-pixel storage enables the pixel to operate either in a low noise correlated double sampling mode with differential PLS, or in an exposure-bracketed high dynamic range imaging (HDR) mode. This HDR mode is successfully demonstrated and yields substantial enhancement of the pixel dynamic range.

This thesis is dedicated to a study of manufacturing of aluminum parts at Alfa company. A complete analysis of the company's main product which are roller doors for commercial vehicles is elaborated. The thesis is based on a existing operation of the company and tries to find the optimal solution for the future. The result is the definition of a new solution and determination it’s operating costs, economic impacts and suggestions for improvement. Key words roller door, aluminum profiles, slat, roller shutter, manufacturing of aluminum parts.

Infrared (IR) illumination is commonly found in a surveillance camera to improve night-time recording quality. However, the limited available power from Power over Ethernet (PoE) connection in networkenabled cameras restricts the possibilities of increasing image quality by allocating more power to the illumination system.The thesis explored an alternative way to improve the image quality by using strobed IR illumination. Different strobing methods will be discussed in relation to the rolling shutter timing commonly used in CMOS sensors. The method that benefits the evaluation scenario the most was implemented in a prototype which is based on a commercialized fixed-box camera from Axis. The prototype demonstrated how the synchronization of the sensor and the strobing illumination system can be achieved.License plate recognition (LPR) in a dark highway was chosen as the evaluation scenario and an analysis on the car movements was done in a pursue of creating an indoor test. The indoor test provided a controlled environment while the outdoor test exposed the prototype to real-life conditions. The test results show that with strobed IR, the output image experienced brightness improvement and reduction in rolling shutter artifact, compared to constant IR. The theoretical calculation also proved that these improvement does not compromise the average power consumption and eye-safety level of the illumination system. / Infraröd (IR) belysning påträffas ofta i övervakningskameror för att förbättra bildkvalitén vid videoinspelning på natten. Den begränsade tillgängliga effekten från Power over Ethernet-anslutningen (PoE) i nätverksaktiverade kameror sätter dock en övre gräns för hur mycket effekt som kameran tillåts använda till belysningssystemet, och därmed hur pass mycket bildkvalitén kan ökas.I detta examensarbete undersöktes ett alternativt sätt att förbättra bildkvalitén genom att använda blixtrande (eng: ”strobed”) IR-belysning. Olika strobe-metoder undersöktes i relation till rullande slutare, vilket är den slutar-metod som vanligtvis används i CMOS-sensorer. Den metod som gav mest fördelaktiga resultat vid utvärdering implementerades i en prototyp baserad på en kommersiell nätverkskamera av Fixed box-typ från Axis Communications. Denna prototyp visade framgångsrikt ett koncept för hur synkronisering av bildsensorn och belysningssystemet kan uppnås.Registreringsskyltigenkänning (LPR) på en mörk motorväg valdes som utvärderingsscenario och en analys av bilens rörelser gjordes för att skapa en motsvarande testuppställning inomhus. Inomhustesterna gav en kontrollerad miljö medan testerna utomhus utsatte prototypen för verkliga förhållanden. Testresultaten visar att med strobed IR blev bilden från kameran både ljusare och uppvisade mindre artefakter till följd av rullande slutare, jämfört med konstant IR-belysning. Teoretiska beräkningar visade också att dessa förbättringar inte påverkar varken kamerans genomsnittliga effektförbrukning eller ögonsäkerheten för belysningssystemet negativt.

The power and energy optimization of a device can lead to a reduced cost, smaller area, better temperature performance, and higher lifetime. Furthermore, in systems that have limited power budget, it allows running simultaneously more functionalities or using features that require higher power demand.Therefore, both from the user and the company perspective, the value of a product increases as the energy optimization improves. For nighttime surveillance video recording, it is common to use infrared illumination to light the targetscene, which draws a significant portion of the total camera energy consumption. This master thesis examines and discusses how stroboscopic infrared illumination can enhance the energy efficiency in videorecording cameras with rolling shutter image sensors. This report analyzes LED driver circuits, recommends methodologies, and sorts the most relevant parameters to help to dimension and design the illumination system for a light-strobing system. A promising field of use for this technique has been found to be the license-plate recognition (LPR) scenario, for which this thesis dedicates a chapter in this document. This project has been developed at AXIS Communications, where a prototype has been built for one of their network security cameras. The prototype has been tested for LPR for both strobing light systems and conventional IR lighting systems. The results obtained prove that the energy efficiency of the illumination system can be improved more than 95% when stroboscopic illumination is used. / Effektförbrukning och energioptimering av en produkt kan leda till lägre kostnad, mindre storlek, bättre temperaturprestanda och högre livslängd. I system med begränsad effektbudget möjliggör detta dessutom aktivering av fler funktioner samtidigt, eller användning av funktioner med högre strömförbrukning. Därmed gör energioptimering att produktens värde ökar både för användaren och för företaget som tillverkar den. För videoinspelning med övervakningskamera nattetid är det vanligt att använda infraröd belysning för att belysa scenen, vilket ofta förbrukar en betydande del av kamerans totala effektbudget. Detta examensarbete undersöker och diskuterar hur blixtrande (Eng. strobed) infraröd belysning kan förbättra energieffektiviteten vid videoinspelning med bildsensorer med rullande slutare. I denna rapport analyseras LED-drivkretsarna, metodik rekommenderas samt att de mest relevanta parametrarna för att dimensionera och designa ett belysningssystem baserad på strobed IR-belysning sorteras ut. Ett lovande användningsområde för denna teknik har visat sig vara LPR-scenariot (License Plate Recognition), vilket diskuteras i ett eget kapitel i denna rapport. Projektet har genomförts på AXIS Communications, där en prototyp har byggts baserat på en av dess nätverkskameror. Prototypen har utvärderats LPR-sammanhang med både strobed och konventionellt IR belysningssystem. De erhållna resultaten visar att energieffektiviteten hos belysningssystemet kan förbättras med mer än 95% när blixtrande belysning används.

This thesis provides theoretical and practical solutions to two problems raised by digital photography of moving scenes, and infrared photography. Until recently photographing moving objects could only be done using short exposure times. Yet, two recent groundbreaking works have proposed two new designs of camera allowing arbitrary exposure times. The flutter shutter of Agrawal et al. creates an invertible motion blur by using a clever shutter technique to interrupt the photon flux during the exposure time according to a well chosen binary sequence. The motion-invariant photography of Levin et al. gets the same result by accelerating the camera at a constant rate. Both methods follow computational photography as a new paradigm. The conception of cameras is rethought to include sophisticated digital processing. This thesis proposes a method for evaluating the image quality of these new cameras. The leitmotiv of the analysis is the SNR (signal to noise ratio) of the image after deconvolution. It gives the efficiency of these new camera design in terms of image quality. The theory provides explicit formulas for the SNR. It raises two paradoxes of these cameras, and resolves them. It provides the underlying motion model of each flutter shutter, including patented ones. A shorter second part addresses the the main quality problem in infrared video imaging, the non-uniformity. This perturbation is a time-dependent noise caused by the infrared sensor, structured in columns. The conclusion of this work is that it is not only possible but also efficient and robust to perform the correction on a single image. This permits to ensure the absence of ''ghost artifacts'', a classic of the literature on the subject, coming from inadequate processing relative to the acquisition model.