Here we present a novel Smartphone-based colorimeter and demonstrate its application to the measurements of glucose and protein concentrations in biological samples. The key innovation of our approach was to combine powerful image processing encoded into a mobile phone application with a low cost 3D printed sample holder that allowed to control lighting conditions and significantly improved sensitivity. Different solutions with protein and glucose concentrations ranging from 0 to 2000 mg/dL were prepared and analyzed using our system. The Smartphone-based colorimeter always correctly classified the corresponding reagent strip pads, what confirms that it can be used as a low cost alternative for commercial test strip analyzers.

This thesis proposes a new chroma keying method that can automatically detect background, foreground, and unknown regions. For background color detection, we use K-means clustering in color space to calculate the limited number of clusters of background colors. We use spatial information to clean the background regions and minimize the unknown regions. Our method only needs minimum inputs from user. For unknown regions, we implement the alpha matte based on Wang's robust matting algorithm, which is considered one of the best algorithms in the literature, if not the best. Wang's algorithm is based on modified random walk. We proposed a better color selection method, which improves matting results in the experiments. In the thesis, a detailed implementation of robust matting is provided. The experimental results demonstrate that our proposed method can handle images with one background color, images with gridded background, and images with difficult regions such as complex hair stripes and semi-transparent clothes.

This thesis aims to evaluate how different mixed reality solutions can be built and whetheror not it could be used for flight simulators. A simulator prototype was implemented usingUnreal Engine 4 with Varjo’s Unreal Engine plugin giving the foundation for the evaluations done through user studies. Three user studies were performed to test subjectivelatency with Varjo XR-1 in a mixed reality environment, test hand-eye coordination withVarjo XR-1 in a video see-through environment, and test the sense of immersion betweenan IR depth sensor and chroma key flight simulator prototype. The evaluation was seenfrom several perspectives, consisting of: an evaluation from a latency perspective on howa mixed reality solution would compare to an existing dome projector solution, how wellthe masking could be done when using either chroma keying or IR depth sensors, andlastly, which of the two evaluated mixed reality techniques are preferred to use in a senseof immersion and usability.The investigation conducted during the thesis showed that while using a mixed realityenvironment had a minimal impact on system latency compared to using a monitor setup.However, the precision in hand-eye coordination while using VST-mode was evaluated tohave a decreased interaction accuracy while conducting tasks. The comparison betweenthe two mixed reality techniques presented in which areas the techniques excel and wherethey are lacking, therefore, a decision needs to be made to what is more important for eachindividual use case while developing a mixed reality simulator.

With the advent of the blockbuster and its visual effects, film has grown to accept these effects and the technology behind them, namely green screen mattes, as cornerstones to the post-production process. The propensity of green screen in all types of productions, especially those involving actors and their performances, raises questions about the methodology and workflow behind its common practice. Using real-life environments and people to create narrative scenes, this project explores the utilization of matte backgrounds to inform the rehearsal and performance aspects of cinematic story-telling.

Esforzados en reproducir una realidad más real que la propia realidad, hace años que las tecnologías de la imagen emplean recursos cada vez más sofisticados con los que elaborar y construir un lenguaje propio. Resulta evidente el desarrollo en estos últimos treinta años de aplicaciones que integran la técnica de chroma-key como un elemento más de su discurso. Este recurso unido a los diferentes medios que lo emplean (Cine, Televisión,Videoarte) supone una ampliación formal y expresiva del lenguaje audiovisual. Realizar un estudio sobre las diferentes aplicaciones que se le ha dado al uso del chroma-key, intentando indagar detrás de la tecnología para ver las necesidades que ha llevado a los autores a escogerla y qué uso hacen de ella y cómo la integran en su discurso. Hemos podido observar que existen diferencias manifiestas en la manera que tienen de aplicar el Cine, la Televisión y el Videoarte estos recursos. En el caso del Cine, nos interesa por su uso casi imperceptible del chroma-key ya en la década de los sesenta. En la Televisión, observamos que en los últimos veinte años se ha incorporado una nueva forma de representación: el decorado virtual. El Videoarte desde su nacimiento (años sesenta) emplea el chroma-key de una manera mucho más evidente, priorizando lo experimental que tiene el medio frente a la ilusión de realidad propia del Cine. A partir de la revolución informática en los noventa, observamos que muchas prácticas artísticas se engloban dentro de lo que se denomina "interactivas". Aquí también hemos encontrado algún ejemplo de utilización del chroma-key, que permite esta interactividad entre los espectadores y la propia obra. El objetivo de este estudio pretende un análisis formal de estas prácticas con chroma-key, con el fin de establecer el uso expresivo que se deriva del empleo de este recurso. / Furió Vita, D. (2008). Posibilidades artísticas de la imagen electrónica: el Chroma-key [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/3343

Title: Cover Song Identification using Music Harmony Features, Model and Complexity Analysis Author: Ladislav Maršík Department: Department of Software Engineering Supervisor: Prof. RNDr. Jaroslav Pokorný, CSc., Department of Software Engineering Abstract: Analysis of digital music and its retrieval based on the audio fe- atures is one of the popular topics within the music information retrieval (MIR) field. Every musical piece has its characteristic harmony structure, but harmony analysis is seldom used for retrieval. Retrieval systems that do not focus on similarities in harmony progressions may consider two versions of the same song different, even though they differ only in instrumentation or a singing voice. This thesis takes various paths in exploring, how music harmony can be used in MIR, and in particular, the cover song identification (CSI) task. We first create a music harmony model based on the knowledge of music theory. We define novel concepts: a harmonic complexity of a mu- sical piece, as well as the chord and chroma distance features. We show how these concepts can be used for retrieval, complexity analysis, and how they compare with the state-of-the-art of music harmony modeling. An extensive comparison of harmony features is then performed, using both the novel fe- atures and the...

In Mixed Reality scenarios, background replacement is a common way to immerse a user in a synthetic environment. Properly identifying the background pixels in an image or video is a dif- ficult problem known as matting. Proper alpha mattes usually come from human guidance, special hardware setups, or color dependent algorithms. This is a consequence of the under-constrained nature of the per pixel alpha blending equation. In constant color matting, research identifies and replaces a background that is a single color, known as the chroma key color. Unfortunately, the algorithms force a controlled physical environment and favor constant, uniform lighting. More generic approaches, such as natural image matting, have made progress finding alpha matte solutions in environments with naturally occurring backgrounds. However, even for the quicker algorithms, the generation of trimaps, indicating regions of known foreground and background pixels, normally requires human interaction or offline computation. This research addresses ways to automatically solve an alpha matte for an image in realtime, and by extension a video, using a consumer level GPU. It does so even in the context of noisy environments that result in less reliable constraints than found in controlled settings. To attack these challenges, we are particularly interested in automatically generating trimaps from depth buffers for dynamic scenes so that algorithms requiring more dense constraints may be used. The resulting computation is parallelizable so that it may run on a GPU and should work for natural images as well as chroma key backgrounds. Extra input may be required, but when this occurs, commodity hardware available in most Mixed Reality setups should be able to provide the input. This allows us to provide real-time alpha mattes for Mixed Reality scenarios that take place in relatively controlled environments. As a consequence, while monochromatic backdrops (such as green screens or retro-reflective material) aid the algorithm’s accuracy, they are not an explicit requirement. iii Finally we explore a sub-image based approach to parallelize an existing hierarchical approach on high resolution imagery. We show that locality can be exploited to significantly reduce the memory and compute requirements of previously necessary when computing alpha mattes of high resolution images. We achieve this using a parallelizable scheme that is both independent of the matting algorithm and image features. Combined, these research topics provide a basis for Mixed Reality scenarios using real-time natural image matting on high definition video sources.

Thesis (M.Sc. Agriculture (Horticulture)) -- University of Limpopo, 2017 / Avocado ‘Hass’ fruit characteristically change skin colour from green to deep purple or black during ripening. However, there is an ongoing debate about the use of ‘Hass’ avocado fruit skin colour change as an indicator for ripening and whether pre- and post-harvest factors can alter this relationship. Thus, the aim of the study was to investigate the effect of harvest season, harvest time, ripening temperature and ripening days on ‘Hass’ avocado fruit skin colour change during ripening. The experiment was carried out as 2 x 3 x 3 x 5 factorial with three replicates. The experiment consisted of four treatment factors: 2 x harvest season (2014 and 2015), 3 x harvest time (May-early, June-mid and July-late), 3 x ripening temperature (16, 21 and 25°C) and 5 x ripening days (0, 2, 4, 6 and 8). Fruit were stored at industry recommended temperature of 5.5°C. After storage, fruit were ripened at 16, 21 and 25°C, therefore, evaluated at 0, 2, 4, 6 and 8 days for subjective and objective skin colour, fruit firmness, ripening percentage and chilling injury. Harvest season, harvest time, ripening temperature and ripening days had a significant effect (P<0.001) on ‘Hass’ avocado fruit skin subjective colour development during ripening. However, amongst the treatment factors; harvest time, ripening temperature and ripening days were the predominant factors in skin subjective colour development variation. Hence, late harvest fruit showed an improved skin colour development at higher temperature (25°C) at day 4 to ripening when compared with early and mid-harvest fruit. Moreover, skin lightness showed a decreasing trend during all harvest time and ripening temperature throughout days to ripening during 2014 and 2015 harvest season. Furthermore, ripening at higher temperature (25°C) resulted in rapid decrease on fruit firmness when compared with lower temperature (16°C), irrespective of harvest season and harvest time. In addition, mid-season fruit showed significantly higher chilling damage during the 2014 harvest season. In conclusion, the study showed that harvest season, harvest time, ripening temperature and ripening days factors had a significant influence on ‘Hass’ avocado fruit skin colour development, firmness and susceptibility to chilling injury. / Agricultural Sector Education Training Authority (AgriSeta) and Postharvest Innovation Programme (PHI)

The execution of this thesis was based on one primare question and threesecondary questions: Primary question at issue: Is it possible to develop a system to previsualize computer generatedgraphics in real-time on a film set with available equipment on theuniversity? Secondary questions at issue: Is it possible to sync the camera feed with the motions of the HTC Vive to getan acceptable result in the game engine with existing equipment? Will the result be able to be integrated with the Computer Graphicsprogramme at LTU? How much access to control and manipulate the previsualized computergenerated graphics, while filming can be achieved? The purpose of this report is to try a method with the available equipment, toproduce a prototype of a tool to previsualize computer generated graphics inreal-time. The equipment used for the method was a computer, web camera, HTC Vive anda green screen. All the equipment was linked together with the game engineUnity. This resulted in a prototype of a tool that in real-time can mimic themotions of the camera, replace colored background and has the feature of realtimescene editing, as the previsualization runs. / Utförandet av detta examensarbete baserades på en primär frågeställning, samttre ytterligare sekundära frågor: Primär frågeställning: Kan man med hjälp av befintlig utrustning på universitetet ta fram enmodell för att previsualisera datorgenererad grafik i real-tid vid en inspelning? Sekundära frågeställningar: Kommer det gå att synka bild från webcamera med fångade rörelser frånHTC Vive och få ett godtagbart resultat från spelmotorn med befintligutrustning? Kan man använda resultatet som ett verktyg för utbildningen Datorgrafikpå LTU? Hur mycket kontroll för den förhandsvisade grafiken går att uppnå i realtid? Syftet med rapporten är att framställa och bepröva en prototyp av en produkt föratt kunna förhandsvisa datorgenererad grafik i real-tid, med befintlig utrustning. Metoden utövades med en dator, web kamera, HTC Vive och en green screen.Genom att använda spelmotorn Unity knöts utrustningen samman för attresultera i en prototyp som i real-tid fångar kamerans rörelser, ersätter färgadbakgrund och kan manipuleras direkt vid inspelning.

The two main goals of my thesis were to further our understanding of how parental effort is related to life-history trade-offs and to see how parental investment is reflected in various potential measures of nestling quality. I looked at how fitness is maximized by examining (1) the trade-off between current and future reproduction, and (2) the trade-off between quantity and quality of offspring. To see how parents responded to energetic demands and whether each sex reacted in a similar way, I experimentally manipulated brood sizes and quantified provisioning rates. Both male and female parents with enlarged broods increased their feeding rates, but provisioning on a per nestling basis declined, so that parents fledged lighter nestlings with shorter wings. Although the incidence of mortality did not differ between control and enlarged broods, nestlings from enlarged broods were lighter than those from control broods with the same brood size, suggesting that clutch size may be individually optimized. I also looked at how nestlings responded to different levels of nutritional stress in the manipulated broods by quantifying size and body condition, plumage colouration, and the physiological measures of T-cell mediated immune responses, and corticosterone levels in nestling feathers as a long-term integrated measure of stress physiology. The size of melanin ornaments on feathers and the saturation and brightness of carotenoid colouration was associated with nestling mass in such a way that suggested that plumage characteristics reflect nestling quality. The immune function of nestlings was negatively related to brood size and nestlings in better body condition could mount greater immune responses to foreign antigens suggesting that immune responses are energetically costly. Corticosterone levels in the feathers were not related to nestling body condition and were unaffected by the experimental brood manipulation. The ii mass of male nestlings, which are the larger sex, was more compromised by brood size than female mass was. I also found sex-specific relationships between plumage characteristics and measures of physiological performance. These findings help to explain optimal clutch size and the classic trade-off between quality and quantity of offspring. They also offer new insights into the reliability of putative measures of quality in nestlings and relationships between physiological and morphological traits.