Le processus de sélection de photos dans des albums peut être considérablement amélioré à l’aide d’un critère d’évaluation automatique des qualités d’une photo. Cependant, les méthodes existantes abordent ce problème de manière indépendante, c’est à dire en évaluant chaque image séparément des autres images d'un album. Dans cette thèse, nous explorons la modélisation du contexte d’une photo via une approche de clustering de collections de photos et la possibilité d'appliquer l’information de contexte à l'évaluation d’une photo. Nous avons effectué des études subjectives permettant d’étudier la manière dont les utilisateurs regroupent et sélectionnent des photos dans un album. Ces études ont permis une estimation du niveau de l’accord entre les différents utilisateurs. Nous avons aussi étudié la manière dont le contexte influence leurs décisions. Après avoir étudié la nature des décisions des utilisateurs, nous proposons une approche informatique pour modéliser leur comportement. Tout d'abord, nous introduisons une méthode de clustering hiérarchique, qui permet de regrouper des photos similaires selon une structure de similarité à plusieurs niveaux, basée sur des descripteurs visuels. Ensuite, les informations de contexte de la photo sont utilisées pour adapter le score de la photo pré-calculé indépendamment, en utilisant les données basées sur des statistiques et une approche d'apprentissage automatique. De plus, comme la majorité des méthodes récentes d'évaluation de la photo sont basées sur des réseaux de neurones convolutionnels, nous avons exploré et visualisé les caractéristiques esthétiques apprises par ces méthodes. / An automatic photo assessment can significantly aid the process of photo selection within photo collections. However, existing computational methods approach this problem in an independent manner, by evaluating each image apart from other images in a photo album. In this thesis, we explore the modeling of photo context via a clustering approach for photo collections and the possibility of applying such context information in photo assessment. To better understand user actions within photo albums, we conduct experimental user studies, where we study how users cluster and select photos in photo collections. We estimate the level of agreement between users and investigate how the context, defined by similar photos in corresponding clusters, influences their decisions. After studying the nature of user decisions, we propose a computational approach to model user behavior. First, we introduce a hierarchical clustering method, which allows to group similar photos according to a multi-level similarity structure, based on visual descriptors. Then, the photo context information is extracted from the obtained cluster data and used to adapt a pre-computed independent photo score, using the statistics-based data and a machine learning approach. In addition, as the majority of recent methods for photo assessment are based on convolutional neural networks, we explore and visualize the aesthetic characteristics learned by such methods.

Made available in DSpace on 2016-04-26T18:10:16Z (GMT). No. of bitstreams: 1 Camila Lopes Garcia.pdf: 4300232 bytes, checksum: e034c96be58a34dffa252f8d510f93ba (MD5) Previous issue date: 2010-10-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The research Collections of floating images: digital online photo albums analyzes the photo collections in the passage of the secondary media to the tertiary media, that is, the transition of the traditional photo album to the digital online photo album put in the social network services, such as Orkut, Facebook and Flickr. The transformations on the amateur photographic habits are analyzed, concerning the filing logic and its social function, due to the technological substitution and the individualization of the machine that produces images. To do so, based on historical and theoretical perspectives, the image is taken in relation to death from the rupestrian paintings to the techno-images, part of Ivan Bystrina s, Edgard Morin s, Régis Debray s and Hans Belting s studies and the sharing of private life photo albums in digital environment, sustained on Vilém Flusser s concepts of no thing , greed and cosmic brain , Norval Baitello s iconography, Dietmar Kamper s visibility crisis , Eugênio Trivinho s ideia of real time existence and Jean Baudrillard s concept of simulacrum . Three digital online photo albums were analyzed, which made possible the identification of two different analyses categories of photo collections on the internet: the ones that give real existence to the network member s profile and the ones that contribute to a common world mapping, due to the use of a search model, or information recovery, by folksonomy tags / A pesquisa "Coleções de imagens flutuantes: álbuns fotográficos digitais on-line" analisa o colecionismo fotográfico na passagem da mídia secundária para a mídia terciária, isto é, na transição do álbum de fotos tradicional para o álbum de fotos digital on-line alocado em redes sociais como o Orkut, o Facebook e o Flickr. São estudadas as transformações ocorridas no hábito fotográfico amador, no que tange à lógica de arquivo e sua função social, em virtude da substituição tecnológica e da individualização do aparelho produtor de imagens. Para tanto, a partir das perspectivas históricas e teóricas, pensa-se a imagem e sua relação com a morte - desde as pinturas rupestres às tecno-imagens, presente nos estudos de Ivan Bystrina, Edgard Morin, Régis Debray e Hans Belting - e o compartilhamento dos álbuns de fotos da vida privada em ambiente digital, apoiando-se nos conceitos de não coisa , gula e cérebro cósmico de Vilém Flusser, na iconofagia de Norval Baitello, na crise da visibilidade de Dietmar Kamper e na ideia de existência em tempo real e simulacro de Eugênio Trivinho e Jean Baudrillard, respectivamente. Três álbuns de fotos digitais on-line foram analisados, o que possibilitou a identificação de duas categorias diferentes de colecionismo fotográfico na internet: os que conferem existência real ao perfil do integrante da rede e os que contribuem para um mapeamento coletivo do mundo, em função da utilização de um modelo de busca, ou recuperação das informações, por meio de tags folksonômicas

Thesis (PhD)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: This study aims to understand the role that 19th century photography can play in the reconstruction of an era and in the conservation of cultural heritage in the 21st century. The photo collection of William Roe, a photographer from Graaff-Reinet, is used as an example. The origin and development of Graaff-Reinet is used as background information and major events such as the Great Trek, the arrival of the railway, the Anglo-Boer War, the First World War and the Great Flu are touched upon. Aspects such as education, churches, the library and the hospital in Graaff-Reinet complement the study. An overview of the development of photography covers several early photo-making processes. These include the daguerreotype process, Talbot's paper negative process, collotype and the popular carte de visite photographs. Photography specifically in South Africa is also conferred, with particular reference to the first photographers working in the country. Reference is made to the important influences major events like the discovery of diamonds and gold as well as the Anglo-Boer War had on photography. The discussion of William Roe as human being and his legacy as a photographer forms an integral part of the study. The Victorian period is discussed since this was the period in which Roe worked and lived. It had a formative influence on his workmanship. An overview of the Victorian period in England is followed by specific focus on South Africa during this time. The rush to the diamond fields, issues with language and the trends of the times are pointed out. Many of these trends are specifically indicated and discussed as they appear in Roe’s photos. The photos have been categorized to clarify analysis of the different cultural phenomena. The architecture and historical background of Graaff-Reinet’s churches and public buildings are discussed. Streetscapes and images of the town as a whole show the development and daily activities that took place. Photos of clothing represent a reconstruction of the fashions of the concurrent Victorian era and those of public events such as sporting events, celebrations, plays and a gathering during the Anglo-Boer War, display the social life of the community. The role of human memory in the writing of cultural history is compared with the “memory” role of photographs. At the same time the ability of photographs to reflect not only physical culture, but also abstract concepts, receives attention. The use of these abilities of photography in the preservation of culture is a challenge for conservationists of the 21th century. / AFRIKAANSE OPSOMMING: Hierdie studie het ten doel om die rol wat 19de-eeuse fotografie kan vervul in die rekonstruksie van ’n era en in die bewaring van kultuurgoedere vir die 21ste eeu, aan te spreek. Die fotoversameling van William Roe van Graaff-Reinet word as voorbeeld gebruik. Die ontstaan en ontwikkeling van Graaff-Reinet word as agtergrond behandel en belangrike gebeurtenisse soos onder meer Die Groot Trek, die koms van die spoorlyn, die Anglo- Boereoorlog, die Eerste Wêreldoorlog en die Groot Griep word uitgewys. Aspekte soos opvoeding, kerke, die biblioteek en hospitaal is aanvullend bestudeer om ’n volledige beeld van Graaff-Reinet daar te stel. ’n Oorsig oor die ontwikkeling van fotografie dek verskeie vroeë fotoprosesse soos die daguerreoproses, Talbot se papiernegatief, die calotipe-fotoproses en die gewilde carte-devisite- foto's. Fotografie in Suid-Afrika word bespreek met spesifieke verwysing na die eerste fotograwe wat in die land werksaam was. Daar word verwys na die invloed wat belangrike gebeurtenisse soos die ontdekking van diamante en goud, asook die Anglo-Boereoorlog, op fotografie in Suid-Afrika gehad het. Die ondersoek na William Roe as mens sowel as sy nalatenskap as fotograaf vorm ’n belangrike onderdeel van die studie. Die Victoriaanse era word bespreek aangesien dit die tydperk was waarin Roe geleef en gewerk het, en dus ’n vormende invloed op sy werk gehad het. ’n Oorsig oor die Victoriaanse era in Engeland word gevolg deur ’n beskouing van dié era in Suid-Afrika. Die stormloop na die diamantvelde, taalkwessies en heersende modeneigings word uitgewys. Baie van die modeneigings word tydens die ontleding van die kultuurverskynsels op die Roe-foto’s opgemerk en bespreek. Die foto’s vir die ontleding van kultuurverskynsels is in kategorieë ingedeel. Die argitektuur en historiese agtergrond van kerke en openbare geboue word bespreek. Straat- en dorpsbeelde dui die ontwikkeling van en bedrywighede op die dorp aan. Kleredragfoto’s bied ’n rekonstruksie van die modes van die Victoriaanse era terwyl die foto’s van openbare geleenthede soos sportbyeenkomste, feesvieringe, toneelopvoerings asook ’n samekoms tydens die Anglo-Boereoorlog die sosiale lewe van die inwoners van die dorp aandui. Die rol van die menslike geheue in kultuurgeskiedskrywing word vergelyk met die rol van foto’s as “geheue”. Terselfdertyd word die vermoë van foto’s om nie net fisiese kultuur te weerspieël nie, maar ook abstrakte konsepte te verteenwoordig, behandel. Die aanwending van hierdie eienskappe van fotografie in kultuurbewaring is ’n uitdaging vir bewaringskundiges van die 21ste eeu.