Monocular depth estimation in images and sequences using occlusion cues

When humans observe a scene, they are able to perfectly distinguish the different parts composing it. Moreover, humans can easily reconstruct the spatial position of these parts and conceive a consistent structure. The mechanisms involving visual perception have been studied since the beginning of neuroscience but, still today, not all the processes composing it are known. In usual situations, humans can make use of three different methods to estimate the scene structure. The first one is the so called divergence and it makes use of both eyes. When objects lie in front of the observed at a distance up to hundred meters, subtle differences in the image formation in each eye can be used to determine depth. When objects are not in the field of view of both eyes, other mechanisms should be used. In these cases, both visual cues and prior learned information can be used to determine depth. Even if these mechanisms are less accurate than divergence, humans can almost always infer the correct depth structure when using them. As an example of visual cues, occlusion, perspective or object size provide a lot of information about the structure of the scene. A priori information depends on each observer, but it is normally used subconsciously by humans to detect commonly known regions such as the sky, the ground or different types of objects. In the last years, since technology has been able to handle the processing burden of vision systems, there has been lots of efforts devoted to design automated scene interpreting systems. In this thesis we address the problem of depth estimation using only one point of view and using only occlusion depth cues. The thesis objective is to detect occlusions present in the scene and combine them with a segmentation system so as to generate a relative depth order depth map for a scene. We explore both static and dynamic situations such as single images, frame inside sequences or full video sequences. In the case where a full image sequence is available, a system exploiting motion information to recover depth structure is also designed. Results are promising and competitive with respect to the state of the art literature, but there is still much room for improvement when compared to human depth perception performance.Quan els humans observen una escena, son capaços de distingir perfectament les parts que la composen i organitzar-les espacialment per tal de poder-se orientar. Els mecanismes que governen la percepció visual han estat estudiats des dels principis de la neurociència, però encara no es coneixen tots els processos biològic que hi prenen part. En situacions normals, els humans poden fer servir tres eines per estimar l’estructura de l’escena. La primera és l’anomenada divergència. Aprofita l’ús de dos punts de vista (els dos ulls) i és capaç¸ de determinar molt acuradament la posició dels objectes ,que a una distància de fins a cent metres, romanen enfront de l’observador. A mesura que augmenta la distància o els objectes no es troben en el camp de visió dels dos ulls, altres mecanismes s’han d’utilitzar. Tant l’experiència anterior com certs indicis visuals s’utilitzen en aquests casos i, encara que la seva precisió és menor, els humans aconsegueixen quasi bé sempre interpretar bé el seu entorn. Els indicis visuals que aporten informació de profunditat més coneguts i utilitzats són per exemple, la perspectiva, les oclusions o el tamany de certs objectes. L’experiència anterior permet resoldre situacions vistes anteriorment com ara saber quins regions corresponen al terra, al cel o a objectes. Durant els últims anys, quan la tecnologia ho ha permès, s’han intentat dissenyar sistemes que interpretessin automàticament diferents tipus d’escena. En aquesta tesi s’aborda el tema de l’estimació de la profunditat utilitzant només un punt de vista i indicis visuals d’oclusió. L’objectiu del treball es la detecció d’aquests indicis i combinar-los amb un sistema de segmentació per tal de generar automàticament els diferents plans de profunditat presents a una escena. La tesi explora tant situacions estàtiques (imatges fixes) com situacions dinàmiques, com ara trames dins de seqüències de vídeo o seqüències completes. En el cas de seqüències completes, també es proposa un sistema automàtic per reconstruir l’estructura de l’escena només amb informació de moviment. Els resultats del treball son prometedors i competitius amb la literatura del moment, però mostren encara que la visió per computador té molt marge de millora respecte la precisió dels humans

A Thousand Futures: A Search for Scenario Space

Although both science fiction and professional foresight work both are engaged with what the future might look like, they operate mostly independently from one another. A literature search reveals the characteristics of written science fiction and foresight, seeking ways these practices could be successfully combined. Concepts are explored through the example of agriculture and agricultural technology as well as technologies for constructing narrative semantics. Approaches are outlined for generating foresight scenarios and for creating a semantic tagging system for generating a semantic space for scenarios using intellectual technologies from science fiction

Remote Sensing and Geosciences for Archaeology

This book collects more than 20 papers, written by renowned experts and scientists from across the globe, that showcase the state-of-the-art and forefront research in archaeological remote sensing and the use of geoscientific techniques to investigate archaeological records and cultural heritage. Very high resolution satellite images from optical and radar space-borne sensors, airborne multi-spectral images, ground penetrating radar, terrestrial laser scanning, 3D modelling, Geographyc Information Systems (GIS) are among the techniques used in the archaeological studies published in this book. The reader can learn how to use these instruments and sensors, also in combination, to investigate cultural landscapes, discover new sites, reconstruct paleo-landscapes, augment the knowledge of monuments, and assess the condition of heritage at risk. Case studies scattered across Europe, Asia and America are presented: from the World UNESCO World Heritage Site of Lines and Geoglyphs of Nasca and Palpa to heritage under threat in the Middle East and North Africa, from coastal heritage in the intertidal flats of the German North Sea to Early and Neolithic settlements in Thessaly. Beginners will learn robust research methodologies and take inspiration; mature scholars will for sure derive inputs for new research and applications

Transformation in Composition

This study enlarges on the notion of composition in landscape architecture. It builds upon the ‘Delft method’, which elaborates composition as a methodological framework from its sister discipline architecture. At the same time takes a critical stance in respect to this framework, informed by recent epistemological developments in landscape architecture such as the site-specificity and process discourses. The notion of composition is examined from a historical and theoretical perspective, before turning to an examination of the brownfield park project realised in the period 1975-2015. These projects emerge as an important laboratory and catalyst for developments in landscape architecture, whereby contextual, process, and formal-aesthetic aspects emerge as central themes. The thesis of this research is that a major theoretical and methodological expansion of the notion of composition can be distilled from the brownfield park project, in which seemingly irreconcilable paradigms such as site and process are incorporated. By extension, the study elaborates on the disciplinary specificity of landscape architecture as distinct to its sister disciplines architecture and urbanism, propositioning a ‘radical maturation’ of the foundations of the discipline in the period 1975 – 2015, via the brownfield park project. A metaphor for this process is offered by the phenomenon of ecdysis in arthropods (such as the blue swimmer crab), whereby the growth from juvenile to adult takes place in stages involving the moulting of an inelastic exoskeleton. Once shed, a larger exoskeleton is formed, whose shape and character is significantly different to its forebears. The research sketches the contours of a similar ‘disciplinary ecdysis’ in the period 1975-2015, whereby an evolution of design-as-composition praxis in landscape architecture takes place. In the slipstream of these findings, the research sheds new light on the shifts in the form and content of the city itself in this period, and the agency of the urban park in the problematique of the contemporary urban realm. In the cases studied, the park typology has been able to address problems that much of the traditional apparatus of spatial planning and design has failed to do. By extension, the study reveals that many of the paradigms of urban planning and design are in need of major review in the context of deindustrialization. The urban park typology – in its guise as the brownfield park – also appears also able to shape and qualify larger urban regions. As such, the research highlights the rise of brownfield lands and their impact on the fabric of the city, the life of their inhabitants and the paradigms that dominate urban cultures, in turn fundamentally revising the definitions and agencies of notions such as city, nature and landscape