Humans recognize optical reflectance properties of surfaces such as metal, plastic, or paper from a single image without knowledge of illumination. We develop a machine vision system to perform similar recognition tasks automatically. Reflectance estimation under unknown, arbitrary illumination proves highly underconstrained due to the variety of potential illumination distributions and surface reflectance properties. We have found that the spatial structure of real-world illumination possesses some of the statistical regularities observed in the natural image statistics literature. A human or computer vision system may be able to exploit this prior information to determine the most likely surface reflectance given an observed image. We develop an algorithm for reflectance classification under unknown real-world illumination, which learns relationships between surface reflectance and certain features (statistics) computed from a single observed image. We also develop an automatic feature selection method.

In the absence of cues for absolute depth measurements as binocular disparity, motion, or defocus, the absolute distance between the observer and a scene cannot be measured. The interpretation of shading, edges and junctions may provide a 3D model of the scene but it will not inform about the actual "size" of the space. One possible source of information for absolute depth estimation is the image size of known objects. However, this is computationally complex due to the difficulty of the object recognition process. Here we propose a source of information for absolute depth estimation that does not rely on specific objects: we introduce a procedure for absolute depth estimation based on the recognition of the whole scene. The shape of the space of the scene and the structures present in the scene are strongly related to the scale of observation. We demonstrate that, by recognizing the properties of the structures present in the image, we can infer the scale of the scene, and therefore its absolute mean depth. We illustrate the interest in computing the mean depth of the scene with application to scene recognition and object detection.

The central challenge in face recognition lies in understanding the role different facial features play in our judgments of identity. Notable in this regard are the relative contributions of the internal (eyes, nose and mouth) and external (hair and jaw-line) features. Past studies that have investigated this issue have typically used high-resolution images or good-quality line drawings as facial stimuli. The results obtained are therefore most relevant for understanding the identification of faces at close range. However, given that real-world viewing conditions are rarely optimal, it is also important to know how image degradations, such as loss of resolution caused by large viewing distances, influence our ability to use internal and external features. Here, we report experiments designed to address this issue. Our data characterize how the relative contributions of internal and external features change as a function of image resolution. While we replicated results of previous studies that have shown internal features of familiar faces to be more useful for recognition than external features at high resolution, we found that the two feature sets reverse in importance as resolution decreases. These results suggest that the visual system uses a highly non-linear cue-fusion strategy in combining internal and external features along the dimension of image resolution and that the configural cues that relate the two feature sets play an important role in judgments of facial identity.

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Our premiss in this study is the escalating competition in the swedish newspaper market, which have become an issue regarding smaller editions for the newspapers, and some scientist have claimed that this has brought an sensational touch to their news. With this in mind, we have studied if a sensational touch is brought to the two biggest Swedish newspapers Aftonbladet’s and Expressen’s first pages. Our purpose with the study is to look into the newspapers development regarding a more sensational newsworthiness on the front page over time. The use of quotes, images and news themes is indicators to measure the development. Trough a content analysis from three different years, 1972, 1992 and 2012 we have measured the data with the computer program SPSS. Our results of the study have showed a development that confirms the scientists’ point of view within this area. We can show a significant increase in the use of quotes, images and a change of common news themes. Classic digging journalism has been replaced by entertainment and more gossip on the first page. We can therefore confirm that there has been a development to a more sensational angle in the news headlines on the first page in the Swedish newspaper market. We’re suggesting further studies within the area, among other things what this development can mean seen trough a democratic point of view, when serious journalism can’t be afford to be produced.

Lynching photographs and images of spectacle lynching were originally produced to commemorate and celebrate lynching. Through processes of rhetorical re-circulation and repurposing of lynching photographs by those in the anti-lynching movement, lynching and visual representations of it became socially unacceptable. The rhetorical strategies concerning the display of images of violence toward African Americans developed in the anti-lynching movement became one of the most important means of protesting civil rights violations in the United States. This study examines three cases of repurposing lynching photographs during the peak of the anti-lynching movement in the 1930’s. The first is the NAACP sponsored Art Commentary on Lynching. I examine four pieces of art in this exhibition that violate the conventions of lynching photography by representing the lynching in other visual mediums that allow the artists to manipulate the lynching scene. The second chapter examines the generation and circulation of an anti-lynching pamphlet featuring a photograph of the lynching of Rubin Stacy. The photograph is repurposed through the interaction of text and image in the pamphlet in a series of rhetorical questions, details of the case, and general information about lynching. The third case is the song, “Strange Fruit.” The song conjures an image through its use of ekphrasis, and suggests a particular reading of that image throughout the performance of the song. I focus on Billie Holiday’s rendition of the song, but draw conclusions about the song and its various performances and recordings. I argue that the use and manipulation of lynching photographs raised social consciousness and public awareness in opposition to spectacle lynching, and re-articulated the meaning of violence, and representations of violence, toward African Americans in the public sphere.

This thesis is based on a field study conducted in Ghana's capital Accra between September and November 2010 where data, in the form of inter alia interviews with Ghanaian university students, was collected. The underlying aim for the study is to gain a deeper understanding for the many times troublesome nation-building process in the African context. The thesis' objective then is to gain a deeper understanding of a part of the "successful" Ghanaian nation-building process and the national identification in Ghana via the concept of national self-images: the affective and cognitive views of the own nation and people. The Ghanaian national identification is explored via the concept which here is divided into two wide dimensions (the Temporal and Relational - primarily based on the works by Bo Petersson and Noel Kaplowitz) and the data is then organised and analysed according to these. The national self-images are further divided into positive respective negative images with presumably disitnct influences on national and political stability. The result from this study is is that the interviewed university students hold predominantely positive images of their own nation, people and polity which may indicate a continued support for the nation-building process. Howeer also osome negative images exist which could hold the potential threat of weakening the support and trust for the national project among the students.

The presence of autonomous systems is becoming more and more common in today’s society.The contexts in which these kind of systems appear are numerous and the variations arelarge, from large and complex systems like autonomous mining platforms to smaller, moreeveryday useful systems like the self-guided vacuum cleaner. It is essential for a completelyself-supported mobile robot placed in unknown, dynamic or unstructured environments tobe able to localise itself and find its way through maps. This localisation problem is stillnot completely solved although the idea of completely autonomous systems arose in thehuman society centuries ago. Its complexity makes it a wide-spread field of reasearch evenin present days. In this work, the localisation problem is approached with an appearance based method forplace recognition. The objective is to develop an algorithm for fast pose hypotheses generationfrom a map. A database containing very low resolution images from urban environmentsis built and very short image retrieval times are made possible by application of imagedimension reduction. The evaluation of the database shows that it has real time potential becausea set of pose hypotheses can be generated in 3-25 hundreds of a second depending onthe tuning of the database. The probability of finding a correct pose suggestion among thegenerated hypotheses is as high as 87%, even when only a few hypotheses are retrieved fromthe database.

This paper is intended to serve as a supporting document for the exhibition This Site Is Under Construction that was held at the University of Waterloo Art Gallery, University of Waterloo, April 17th – May 14th, 2010. The work explores the ways in which we constitute and mediate our specific place in a space that is constantly changing. It is concerned with notions surrounding how we make and perceive images now in our computerized visual culture and the ways in which we can mark a subjective painting aesthetic and visual vocabulary. The painting installation, “This Site Is Under Construction”, investigates the effects of new media and digitization on experiential perception, and the nature of making and re-configuring images. The title alludes not only to the on-line, virtual space of the computer, but also to the physical spaces of building and urban development sites. The subjects for the paintings are spaces in flux – specific locales of construction and building sites that are in-between states of development – placing emphasis on the mechanized devices that fabricate the new structures. The paintings themselves reveal seemingly spontaneous and optically warped immersive spaces; alternative architectural environments which subvert interpretations of two-dimensional and three-dimensional forms of visual presentation and recognition. The work aims to contrast outward appearance and illusionistic staging as it relates to both the picture and its support.

This thesis aims to explore and describe the images of China in the Western tourist material. There is much literature talking about images of China; however, among the existing scholarship so far few have investigated from the angle as we do. We use social constructivism and representation as main theories and combined with central concepts of the tourist gaze, stereotypes and the other, and post-colonialism and orientalism. Moreover, we conduct a case study by applying qualitative discourse analysis in order to find out the stereotypes and orientalist ideas of China depicted in the tourist material. The findings show that in the perspective of western tourist material, China is representative of the Orient. The analysis also concludes that China is seen as a country with 5,000-year civilization whose people have lots of virtues; a developing economic power; a not so democratic socialist country; a potential threat and a global actor with increasing influences. Our thesis contributes to the existing literature on China research and tourism research—marketing and political implications for its national image improvement and tourism development.