Digital inpainting is the technique of filling in the missing regions of an image or a video using information from surrounding area. This technique has found widespread use in applications such as restoration, error recovery, multimedia editing, and video privacy protection. This dissertation addresses three significant challenges associated with the existing and emerging inpainting algorithms and applications. The three key areas of impact are 1) Structure completion for image inpainting algorithms, 2) Fast and efficient object based video inpainting framework and 3) Perceptual evaluation of large area image inpainting algorithms. One of the main approach of existing image inpainting algorithms in completing the missing information is to follow a two stage process. A structure completion step, to complete the boundaries of regions in the hole area, followed by texture completion process using advanced texture synthesis methods. While the texture synthesis stage is important, it can be argued that structure completion aspect is a vital component in improving the perceptual image inpainting quality. To this end, we introduce a global structure completion algorithm for completion of missing boundaries using symmetry as the key feature. While existing methods for symmetry completion require a-priori information, our method takes a non-parametric approach by utilizing the invariant nature of curvature to complete missing boundaries. Turning our attention from image to video inpainting, we readily observe that existing video inpainting techniques have evolved as an extension of image inpainting techniques. As a result, they suffer from various shortcoming including, among others, inability to handle large missing spatio-temporal regions, significantly slow execution time making it impractical for interactive use and presence of temporal and spatial artifacts. To address these major challenges, we propose a fundamentally different method based on object based framework for improving the performance of video inpainting algorithms. We introduce a modular inpainting scheme in which we first segment the video into constituent objects by using acquired background models followed by inpainting of static background regions and dynamic foreground regions. For static background region inpainting, we use a simple background replacement and occasional image inpainting. To inpaint dynamic moving foreground regions, we introduce a novel sliding-window based dissimilarity measure in a dynamic programming framework. This technique can effectively inpaint large regions of occlusions, inpaint objects that are completely missing for several frames, change in size and pose and has minimal blurring and motion artifacts. Finally we direct our focus on experimental studies related to perceptual quality evaluation of large area image inpainting algorithms. The perceptual quality of large area inpainting technique is inherently a subjective process and yet no previous research has been carried out by taking the subjective nature of the Human Visual System (HVS). We perform subjective experiments using eye-tracking device involving 24 subjects to analyze the effect of inpainting on human gaze. We experimentally show that the presence of inpainting artifacts directly impacts the gaze of an unbiased observer and this in effect has a direct bearing on the subjective rating of the observer. Specifically, we show that the gaze energy in the hole regions of an inpainted image show marked deviations from normal behavior when the inpainting artifacts are readily apparent.

Η ραγδαία αύξηση των εικόνων, σε συνδυασμό με την αδυναμία των συστημάτων ανάκτησης εικόνας βάσει περιεχομένου να εξάγουν σημασιολογικά χαρακτηριστικά, οδήγησαν στην εισαγωγή του ανθρώπινου παράγοντα στην πειραματική διαδικασία. Ένας πολύ συνηθισμένος και επιτυχημένος τρόπος χρησιμοποίησης του ανθρώπινου συστήματος όρασης είναι μέσω της καταγραφής των οφθαλμικών κινήσεων. Στο σύστημα ανάκτησης το οποίο προτείνεται στην παρούσα εργασία γίνεται καταγραφή των σημείων εστίασης που προέκυψαν κατά την παρατήρηση των εικόνων βάσεως. Από τα σημεία αυτά, γίνεται εξαγωγή χαρακτηριστικών υφής με δύο μεθόδους, τα φίλτρα Gabor και το διακριτό μετασχηματισμό συνημιτόνου (DCT), παράγοντας πολυδιάστατα διανύσματα. Τα διανύσματα αυτά συγκρίνονται ανά δύο μέσω του μη παραμετρικού WW test, δημιουργώντας έναν πίνακα αποστάσεων. Με την εισαγωγή μιας ζητούμενης εικόνας στο σύστημα, τα χαρακτηριστικά υφής της συγκρίνονται με αυτά της βάσης προσθέτοντας μια επιπλέον διάσταση στον πίνακα απόστασης. Η απεικόνιση της σχέσης μεταξύ όλων των εικόνων (συμπεριλαμβανομένης και της αιτούμενης) γίνεται σε ένα χάρτη τριών διαστάσεων μέσω πολυδιάστατης κλιμάκωσης (MDS αλγόριθμος). Τα αποτελέσματα τα οποία προέρχονται από τα φίλτρα Gabor παρουσιάζουν μεγαλύτερη αξιοπιστία, κάνοντας εφικτή την επέκταση του συστήματος με χρήση μίας μεγαλύτερης βάσης εικόνων. / The rapid increase of images, combined with the weakness of the Content Based Image Retrieval (CBIR) systems to extract semantic features, led to the introduction of the human factor into the experimental procedure. A very common and successful way of using the human vision system is through the record of eye movements. In the retrieval system which is proposed in the present thesis, the fixation points that arose from viewing the database images are recorded. From these points, the texture features are extracted using two methods, Gabor filters and Discrete Cosine Transform (DCT), producing multidimensional vectors. These vectors are compared through the non parametric WW test, creating a distance matrix. By producing a query image in the system, its’ texture features are compared to those of the database, adding an extra dimension to the distance matrix. The visual representation of the relation among all the images (query image included), is depicted in a three dimensional map using multidimensional scaling (MDS algorithm). The results obtained from Gabor filters are characterized by higher robustness, making the expansion of the system possible, by using a bigger image database.

Eye tracking technology has made it possible to accurately and consistently track a users gaze position on a screen. The human eyes center of focus, where it can see the most detailed information, is quite small at a given moment. The peripheral vision of humans have a much lower level of details than the center of gaze. Knowing this, it is possible to display a view that increases the level of resolution at the position of the users gaze point on the screen, while the rest of the screen keeps a lower resolution. An implementation of such a system can generate a representation of data with both detail and overview. The results indicate that even with simple gaze data processing it is possible to use gaze control to help explore details of a high resolution image. Gaze data processing often involve a compromise between stability, responsiveness and latency. A low latency, highly responsive gaze data filter would increase the risk for lens oscillation, and demand a higher concentration level from the viewer then a slower filter would. Applying a gaze data filter that allowed for smooth and stable lens movement for small saccades and responsive movements for large saccades proved successfully. With the uses of gaze control the user might be able to use a gaze aware application more efficient since gaze precedes actions. Gaze control would also reduce the need for hand motions which could provide a improved work environment for people interacting with computer.

This thesis deals with use of Information technology for analysis of exposure to advertising communications, focusing on outdoor advertising.In the theoretical part is a brief outline of the beginnings and development of advertising, its effects on people, whether it can change their consumption behaviour, its position in the modern world and the way new technology along with psychology can be used for its analysis. The second part gives insight in the practical research of effects of outdoor advertising on people. There is an approach of Eye Camera technology in praxis, preparation for research, problems solved in its course. Data obtained are both verbally and graphically interpreted.

Background. Visual attention in video games is a relatively underdeveloped field, especially so when it comes to colorblind accessibility. According to recent research, there is an increased social demand for options to alleviate problems colorblind individuals experience in video games. Finding simple and effective ways to achieve visual attention, which work well for both colorblind individuals and non-colorblind individuals simultaneously, would therefore be beneficial to the video game industry. Objectives. The objectives of this thesis were to analyze the effectiveness of three already utilized methods for achieving visual attention in video games and how their effectiveness differs when seen from a trichromatic or dichromatic perspective. The selected methods are animation, color, and outline. These are commonly used in video games, not only for the sake of attention but also for design in general. By testing each method individually and combined with color it is possible to analyze their effectiveness and how it differs when seen from different color perspectives. Methods. In order to gather the data required, an eye-tracking experiment with a sample size of 20 participants was conducted. The experiment showed scenes consisting of either a control background or game-inspired background. The scenes contained two objects which had color, animation, outline, animation combined with color, or outline combined with color applied to them. This experiment was performed on campus, so the primary group tested were students. The eye-tracker analyzed the participant's eye movements and together with areas of interest, it provided two different metrics: time to first fixation and total fixation duration. Results. The results of the experiment show that animation was the best-performing method for achieving visual attention in a video game regardless of which colorblind perspective it was seen from, both in terms of time to first fixation and total fixation duration. Out of red, green, blue, and yellow which were the colors tested, yellow was the best-performing color in terms of average time to first fixations and total fixation duration across all colorblind perspectives. However, green was the most consistent color from all perspectives. Conclusions. The eye-tracking method used for gathering the data provided good results. Out of animation, color, and outline, animation was substantially better at achieving visual attention compared to the other two methods. A noticeable difference in attention can also be found depending on what chromatic perspective the scenes were viewed from. This thesis serves as a way to raise awareness about visual attention in video games, and examples of how the results can be utilized are provided. The experiment could be used as inspiration for future work within the field, where a larger sample size and more methods for achieving visual attention could be tested.

Clinicians are becoming increasingly aware of the effect of various pathologieso n the characteristicso f saccadice ye movements.A s such, an efficient and non-invasivem eano f measuringe ye-movementisn a clinical environmenti s of interest to many. The aim of this thesis is to investigate the clinical application of a non-invasive eye movement recording technique as a part of a clinical examination. Eye movements were measured using an IRIS 6500 infrared limbal eye tracker, which we customized for the direct recording of oblique eye movements as well as horizontal and vertical. Firstly, the eye-tracker itself was assessed. Visually normal observers made saccadic eye movements to a 10' stimulus in eight directions of gaze. Primary (ANOVA) and secondary analyses (mean error less than 5%) resulted in acceptance that averaging four measurements would give a representative measurement of saccadic latency, peak velocity, amplitude and duration. Test-retest results indicated that this technique gives statistically (± 1.96*STDEVDifference) repeatable responses. Severalf actors that could potentially influence clinically basedm easureso f eye-movementsw ere examined. These included, the effect of ageing, viewing distances, dioptric blur and cataract. The results showed that saccadic latency and durationa re significantly (p< 0.05) longer in older (60-89 years)o bserversc ompared to younger (20-39 years). Peak velocity and amplitude were not significantly affectedb y the age of the observer.A ll saccadicp arameters( SP) were significantly affected by direction (Chapter 5). The compact nature of this eye movement methodology is obtainable since there is no significant effect on viewing distance (300 cm vs. 49 cm) (Chapter 6). There is also no significant effect of dioptric blur (up to +LOODS) on any of the four SP. In contrast, a higher level of defocus (+3.O ODS)h as a larger probability of interfering with the measurementso f peak velocity and duration (Chapter 7). Saccadice ye-movementsw ere also recorded whilst normally sighted subjects wore cataract simulation goggles. The results suggested that the presence of dense cataract introduces significant increases in saccadic latencies and durations. No effect was found on the peak velocities and amplitudes.T he effect of amblyopiao n SP was also investigatedin order to examine if this methodologyi s able to detectn ormal from abnormalr esponses(i . e. increased saccadicla tencies).T his set of data (Chapter9 ) showedt hat using IRIS 6500, longer than normal latencies may be recorded from the amblyopic eye but no consistent effect was found for the other SP (peak velocity, amplitude, duration). overall, the results of this thesis demonstrateth at the IRIS 6500 eye-tracker has many desirable elements (it is non-invasive; comfortable for the observers and gives repeatable and precise results in an acceptable time) that would potentially make it a useful clinical tool as a part of a routine examination.

If researchers are able to derive usability simply by analysing gaze data it provides a quick, objective and potentially automatic way of measuring the usability of an interface. In order to do that it is essential to know which traits of the gaze data that have an impact on usability. This paper investigates these traits by analysing different eye tracking metrics in the data. The goal is to see which of these metrics have a general correlation with usability. Previous research provides a clue about which metrics are useful when analysing usability. However, much of the research is based on subjective analysis or lacks in general applicability. This research provides an objective analysis that is independent of characteristics of the interface. A user study is done on 20 participants. They complete tasks on nine different ecommerce websites while their eye movements are recorded. Correlation is measured between usability and eye tracking metrics in order to investigate which metrics that are sensitive to changes in usability. The results show that fixational backtracks and number of fixations have the strongest correlation with usability. Previous research did suggest that both of these eye tracking metrics have an impact on usability. / Om det är möjligt för forskare att härleda användbarhet endast genom att analysera ögondata så tillhandahålls ett snabbt, objektivt och potentiellt automatiserat sätt att mäta användbarheten hos ett gränssnitt. För att göra detta är det avgörande att veta vilka karakteristiska drag i ögondatan som påverkar användbarheten. Denna rapport utforskar dessa drag genom att analysera olika mått i ögondatan. Målet är att se vilka av dessa mått som uppvisar en generell korrelation med användbarhet. Tidigare forskning förser oss med ledtrådar om vilka mått som är lämpliga att analysera när användbarhet ska mätas. Dock så är mycket av denna forskning baserad på subjektiv analys eller saknar generell tillämpbarhet. Denna rapport tillhandahåller en objektiv analys som är oberoende av karakteristiken hos gränssnittet. En användarstudie utförs på 20 deltagare. De utför uppgifter på nio olika webbsidor för e-handel medan deras ögonrörelser spelas in. Korrelation mäts mellan användbarhet och mått i ögondatan för att undersöka vilka mått som är känsliga för förändringar i användbarhet. Resultatet visar att tillbakabildande sackader och antal fixeringar har starkast korrelation med användbarhet. Tidigare forskning visade att båda dessa mått påverkades av användbarheten.

Smarta enheter blir allt vanligare och teknologierna de använder blir allt mer avancerade. Som en följd av detta uppstår bekväma och effektiva lösningar till vardagliga problem. En stor mängd sammankopplade smarta enheter leder dock till system som är svåra att förstå och att använda. Detta ställer krav på lösningar som hjälper användare att interagera med enheter på ett intuitivt och effektivt sätt. En teknik som under de senaste åren blivit allt mer kommersiellt brukbar och som kan användas i detta syfte är augmented reality. Vidare så är spårning av ögonpositioner ett lovande tillvägagångssätt för att navigera virtuella menyer.Denna uppsats har som syfte att utvärdera hur ögon- och huvudrörelser kan kombineras för att låta användare på ett intuitivt sätt interagera med ett gränssnitt i augmented reality. För att uppnå detta tas två interaktionsmetoder fram som använder ögon- och huvudrörelser på något olika sätt. För att utvärdera deras prestanda och användbarhet så utförs ett experiment där deltagarna navigerar en uppsättning menyer både med hjälp av de framtagna metoderna och en beprövad referensmetod.Resultaten från experimentet visar att referensmetoden både är den snabbaste och den minst felbenägna ut av de tre utvärderade metoderna. Trots detta så föredrar deltagarna en av de framtagna metoderna, och båda dessa metoder uppnår adekvata resultat. Vidare så visar den kvantitativa datan inte på några mätbara skillnader mellan de framtagna metoderna. Däremot så uppnår en av dem högre resultat i de subjektiva utvärderingarna. / Smart devices are becoming increasingly common and technologically advanced. As aresult, convenient and effective approaches to everyday problems are emerging. However,a large amount of interconnected devices result in systems that are difficult to understandand use. This necessitates solutions that help users interact with their devices in anintuitive and effective way. One such possible solution is augmented reality, which hasbecome a viable commercial technology in recent years. Furthermore, tracking the positionof users’ eyes to navigate virtual menus is a promising approach that allows for interestinginteraction techniques.In this thesis, we explore how eye and head movements can be combined in an effortto provide intuitive input to an augmented reality user interface. Two novel interactiontechniques that combine these modalities slightly differently are developed. To evaluatetheir performance and usability, an experiment is conducted in which the participantsnavigate a set of menus using both our proposed techniques and a baseline technique.The results of the experiment show that out of the three evaluated techniques, thebaseline is both the fastest and the least error-prone. However, participants prefer oneof the proposed techniques over the baseline, and both of these techniques perform adequately.Furthermore, the quantitative data shows no measurable differences betweenthe proposed techniques, although one of them receives a higher score in the subjectiveevaluations.

Questo studio è composto da due ricerche. La prima riguarda bambini della scuola dell’infanzia di età compresa tra 4 e 6 anni (N=44) ed esplora la comprensione dell’ironia e la sua possibile correlazione tra la comprensione di norme sociali, la teoria della mente e la competenza emotiva. I risultati mostrano come la comprensione delle norme sociali, della loro violazione e le competenze emotive possono aiutare i bambini nella comprensione dell’ironia La seconda ricerca relativa agli adulti (N=88) esplora la correlazione tra teoria della mente ed elaborazione di informazioni ironiche attraverso l’utilizzo dello strumento eye tracker. Lo studio evidenzia relazioni significative tra lo sviluppo della teoria della mente di tipo emotivo e l’elaborazione di informazioni ironiche: nello specifico, si verifica che in presenza di un enunciato ironico, soggetti con una teoria della mente elevata osservano frasi/ disegni che descrivono la realtà dei fatti, mentre soggetti con una teoria della mente meno elevata osservano frasi/ disegni relativi al significato letterale dell’ironia. Ciò sembra confermare il ruolo della teoria della mente nell’elaborare forme di comunicazione non letterali già ad un livello di base, pre-riflessivo come quello qui indagato. / This research consists of two studies. The first, involving school children aged between 4 and 6 years (N = 44), explores the understanding of irony and its possible correlation between social norms understanding, theory of mind and emotional competence. The results show that the understanding of social norms, their violation and emotional skills can help children in irony understanding. The second study related to adults (N = 88), explores the relationship between theory of mind and irony visual elaboration with the eye tracker Instrument. Results found relationships between the development of emotional theory of mind and irony visual elaboration, confirming the role of theory of mind during the growth of the individual to elaborate ironic sentences.

近年來隨著電腦科技的進步，發展出了各種人機介面的應用。不同於傳統的滑鼠與鍵盤，新的人機介面往往在其他不同的領域能夠得到更好的發揮，眼動（eye movement）即是一個例子，利用眼球移動在螢幕上的眼動軌跡來操控電腦。另一方面，螢幕所呈現的內容也會影響使用者的眼動行為，例如閱讀文章時不同的文章內容就會影響使用者在看文章時的眼動行為，因此我們就可以從眼動軌跡去推測出使用者對於螢幕的內容（如文章或圖片）的反應。本論文的目的就是要找出閱讀文章時的眼動軌跡和閱讀者對該文章的理解程度之間的關連性，最後發展出一個系統，利用閱讀文章時的眼動軌跡就能去推測閱讀者對於文章的理解程度，而無需後續的閱讀測驗。 / 一般人通常對自身的眼動軌跡的進行方式不甚了解，認為閱讀文章的眼動應該是順著字句的進行而移動。其實仔細觀察細小的眼動軌跡會發現比想像中複雜的多，例如當我們閱讀到文意較為困難的片段時，通常都會放慢速度，或是反覆閱讀，又例如看到自己有興趣的主題時會凝視在某些區塊較久的時間等等行為，這些都是在各種不同的情境之下做出相對的反應。本論文提出了資料探勘的方法來分析複雜的眼動軌跡，能針對每個人不同的閱讀模式找出不同的眼動規則。此方法能適應各種使用者的閱讀習性，對閱讀理解程度的預測能達到更精確的效果。 / With the advance of the computer technology, there are many kinds of HCI (Human Computer interface) applications been developed in recent years. Different from mouse and keyboard, new interface will bring more benefits in different area, and eye-movement is an example. It extracts the trace of eye movement to control the computer. Furthermore, the screen content will also affect the eye-movement. For example, when the user reads the articles, the content will affect the eye-movement, so we can speculate the reaction of the user after seen the screen content (such as article or picture) by eye-movement. The goal of the paper is to find out the relationship between eye-movement and the degree of comprehension, and develop a system which can automatically measure reading comprehension without any follow-up comprehension test. / Most people don’t realize how there eye move. They think eye movements should be carried out along the words. In fact, eye movement will find more complex than imagined, for example, when we read the context of the article is more difficult, we often slow down or read over and over again. In another example, people will gaze at some of the subjects that they are interest in for a longer period of time. These reactions correspond to a variety of different situations. This paper presents a data mining approach to analyze complex eye movement. It can find out the different rules of eye movement for users who have different reading strategy. This method will be able to adapt to a variety of users reading habits, and make more accurate prediction with the degree of the comprehension.