Bildhantering är idag mer populärt än någonsin. Marknaden erbjuder fler, bättre och enklare kameror vilket resulterar i att allt fler tar bilder för att publicera på olika sätt. Digital bildhantering är mer än bara ett populärt tidsfördriv, det har blivit ett sätt att kommunicera på. Oavsett användningsområde så krävs det mycket av de program och system som hanterar digitala bilder. Det är idag ett stort behov, men också ett krav, i många branscher. Tidigare forskning visar på att det finns en kunskapslucka inom bildhantering ur ett användarcentrerat perspektiv.Denna studie handlar om bildhantering utifrån ett användarcentrerat perspektiv där fokus kommer att ligga på användarupplevelse och informationsarkitektur. För att få en positiv användarupplevelse krävs ett bra användarflöde. Användaren ska inte behöva avbrytas i sitt arbete på grund av en dålig struktur i gränssnittet. Irritation och frustration ska undvikas. Avgränsning i studien har gjorts gällande gränssnitt som hanterar övriga typer av filer samt gränssnitt som ligger på webben och i “molnet”. Syftet med studien är att identifiera viktiga faktorer då användaren strukturerar och hanterar bilder för att bidra till en bättre upplevelse och ett bättre användarflöde. En fallstudie genomfördes för att utvärdera och undersöka gränssnittet för ImageVault, ett digitalt bibliotek för bilder. Uppdragsgivaren i fallstudien var Meriworks AB. Utifrån den teori som studien behandlar har ett antal designprinciper framställts. Dessa designprinciper låg sedan till grund för den heuristiska utvärdering som gjordes för att få en helhetsbild över gränssnittet. För att få ett mer användarcentrerat perspektiv i studien genomförde författarna även 18 intervjuer med befintliga användare av gränssnittet. Intervjufrågor utformades med hjälp av den teori som tagits fram. Baserat på de intervjuer som gjordes har personas och scenarier skapats för att sedan resultera i ett antal mockuper som visar på framtida funktionalitet och struktur över gränssnittet.Studien har fokuserat mycket på att utvärdera ett gränssnitt utifrån användarnas perspektiv, hur uppbyggnaden är gällande ett gränssnitt som hanterar digitala bilder. Författarna strävade efter att ta reda på hur man kan uppfylla användarens behov och mål och samtidigt konstruera ett gränssnitt som hanterar digitala bilder på ett bättre sätt med hjälp av informationsarkitektur och användarflöde. Under studien har författarna identifierat ett antal faktorer som ansetts vara viktiga vid kategorisering och hantering av bilder i digitala bibliotek. Dessa faktorer är ett resultat utifrån studiens teoretiska ramverk och fallstudiens datainsamling tillsammans med de mockuper som skapats. Dessa faktorer kan ligga till grund för att utveckla gränssnitt som behandlar digital bildhantering. Fortsatt forskning behövs för att ta reda på faktorernas validitet men även för att undersöka om dessa faktorer behöver kompletteras ytterligare. / Today imaging is more popular than ever. More pictures will be published in different ways since the market offers more, better and simpler cameras. Digital imaging is more than just a popular time-killer, it has become a way to communicate. Whatever their intended use, it is required a lot from the programs and systems that handle digital images. There is a great need, but also a requirement in many industries. Previous research shows that there is a gap of knowledge in imaging from a user-centered perspective.This essay is about imaging based on a user-centered approach with a focus on user experience and information architecture in the world of digital photo libraries. A positive user experience requires great user flow. The user shouldn’t have to be interrupted in their work due to a poor structure of the interface. Irritation and frustration should be avoided. Interfaces that manage other types of files and interfaces located on the Web and in "the cloud" have been delimited in this essay. The purpose of this essay is to identify important factors when categorizing and managing images for contributing to a better experience and a better user flow. The company Meriworks AB has given the authors the task of evaluating and investigating the interface for ImageVault, a digital library of images. A number of design principles have been created based on the theories that the essay contains. These design principles formed the basis for the heuristic evaluation that was done to give the authors an overview of the interface. To get a more user-centered perspective, 18 interviews with existing users of the interface were carried out. Based on the theories of the essay interview questions were designed. Based on the interviews personas and scenarios were created, to the result in a number of mockups showing future functionality and structure of the interface.The study has focused very much on evaluating an interface based on user perspective and how the structure is built in an interface that manages digital images. The authors aimed to determine how to meet the user's needs and goals and designing an interface that manages digital photos in a better way with the help of information architecture and user flow. During the study, a number of factors have been identified which are considered important for the categorization and management of images in digital photo libraries. These factors are the result, based on the theoretical framework of the essay and the data collection of the case study together with the mockups created. These factors may be the basis for developing interfaces that deal with digital imaging. Further research is needed to find out the validity of the factors, but also to examine whether these factors need to be supplemented further.

Indiana University-Purdue University Indianapolis (IUPUI) / Objective: The objectives of this in-vitro study were: 1) to evaluate the ability of Near-Infrared Digital Imaging Transillumination (NIDIT) to detect non-cavitated approximal caries lesions; and 2) to compare the performance among NIDIT, Digital Radiography (DR), Digital Imaging Fiber-Optic Trans-Illumination (DIFOTI) and International Caries Detection and Assessment System (ICDAS). Methods: Thirty human extracted premolars were selected. The approximal surface status ranged from sound to surfaces with non-cavitated caries lesions into the outer one-third of the dentin. Lesion depth was determined by micro-computed tomography (μ-CT) and used as a gold standard. Teeth were mounted in a custom-made device to simulate approximal contact. ICDAS, DR, DIFOTI and NIDIT examinations were performed and repeated by three trained and calibrated examiners. Sensitivity, specificity, area under ROC curve (Az), inter- and intra-class correlation coefficients (ICCs) of each method, and correlation among the methods were determined. Results: ICCs for intra-/inter-examiner agreement were almost perfect for DIFOTI (0.85/0.83), substantial for ICDAS (0.79/0.72) and NIDIT (0.69/0.64), and moderate for DR (0.52/0.48). Sensitivity/specificity for DIFOTI, ICDAS, DR, and NIDIT were 0.91/0.69, 0.89/0.83, 0.50/0.64, and 0.68/0.93, respectively. Az of DR (0.61) was significantly lower than that of DIFOTI (0.91, p = 0.002) and ICDAS (0.90, p = 0.005), but was not significantly different from NIDIT (0.81, p = 0.052). DIFOTI, ICDAS, and NIDIT were not significantly different from each other (p > 0.13). Spearman correlation coefficients for DIFOTI (0.79, p < 0.001), ICDAS (0.74, p < 0.001), and NIDIT (0.65, p < 0.001) demonstrated a moderate association with μ-CT, while that of DR suggested no association (0.19, p = 0.289). Conclusion: Within the limitations of this in-vitro study, NIDIT system demonstrated a potential for early approximal caries detection. ICDAS, DIFOTI, and NIDIT were superior to DR in terms of validity and reliability.

Solar images are one of the most important sources of available information on the current state and behaviour of the sun, and the PICARD satellite is one of several ground and space-based observatories dedicated to the collection of that data. The PICARD satellite hosts the Solar Diameter Imager and Surface Mapper (SODISM), a telescope aimed at continuously monitoring the Sun. It has generated a huge cache of images and other data that can be analysed and interpreted to improve the monitoring of features, such as sunspots and the prediction and diagnosis of solar activity. In proportion to the available raw material, the little-published analysis of SODISM data has provided the impetus for this study, specifically a novel method of contributing to the development of a system to enhance, detect and segment sunspots using new hybrid methods. This research aims to yield an improved understanding of SODISM data by providing novel methods to tabulate a sunspot and filling factor (FF) catalogue, which will be useful for future forecasting activities. The developed technologies and the findings achieved in this research will work as a corner stone to enhance the accuracy of sunspot segmentation; create efficient filling factor catalogue systems, and enhance our understanding of SODISM image enhancement. The results achieved can be summarised as follows: i) Novel enhancement method for SODISM images. ii) New efficient methods to segment dark regions and detect sunspots. iii) Novel catalogue for filling factor including the number, size and sunspot location. v) Novel statistical method to summarise FFs catalogue. Image processing and partitioning techniques are used in this work; these methods have been applied to remove noise and detect sunspots and will provide more information such as sunspot numbers, size and filling factor. The performance of the model is compared to the fillers extracted from other satellites, such as SOHO. Also, the results were compared with the NOAA catalogue and achieved a precision of 98%. Performance measurement is also introduced and applied to verify results and evaluate proposal methods. Algorithms, implementation, results and future work have been explained in this thesis.

Thesis (MA (VA))--Stellenbosch University, 2012. / ENGLISH ABSTRACT: This study offers a critical exploration of the ways in which Jean Baudrillard’s theory of the simulacrum is ‘true’ or viable as a theory of representation in contemporary visual culture, with particular reference to digital imaging technologies. Using a selection of images and texts dating from the Renaissance to present day, I trace issues of subjectivity and self-reflexivity in modern image culture, questioning the extent to which digital imaging technology and information substantially departs from the early modern devotion to naturalistic representation (verisimilitude) as a reflection of knowledge and truth in the modern world. I offer a critique of the simulacrum theory that concerns two principle issues: firstly that simulacrum is a strictly self-reflexive operation and not an effect of digital imaging technology as Baudrillard claims; and secondly, that simulacrum necessitates an underlying dualist worldview in order to exist. With reference to the use of metaphor in magical realist texts and visual art, I draw the argument together with a discussion of my own art practice, particularly a body of work that takes Etienne van Heerden’s novel Toorberg (1986) as a starting point. The examples I refer to serve as visual evidence in support of my speculative philosophical argument against hyperreality; that is, how the simulacral nature of metaphor (as operating within a poststructuralist model of the sign) functions a critical aspect of a self-reflexive individual consciousness; and argues for subjectivity itself as inherently bound up in the operation of simulacrum. / AFRIKAANSE OPSOMMING: Hierdie studie is ’n kritiese ondersoek na die wyse waarop Jean Baudrillard se teorie van die simulacrum ‘waar’ of grondig is as ’n teorie van representasie in visuele kultuur, met spesifieke verwysing na digitale beeldtegnologie. ‘n Verskeidenheid beelde en tekste (van die Renaissance tot die moderne era) word betrek ten einde kwessies rondom subjektiwiteit en selfrefleksiwiteit in moderne beeldkultuur te ondersoek. Die mate waarin digitale beeldtegnologie en inligting merkbaar afwyk van ‘n vroeë moderne toegewydheid aan naturalistiese representasie (verisimilitude) as ‘n refleksie van kennis en waarheid in die moderne wêreld, word vervolgens krities ondersoek. Baudrillard se simulacrum-teorie word krities beoordeel: in die eerste plek is die simulacrum ‘n streng selfrefleksiewe proses en nie ‘n effek van digitale beeldtegnologie, soos Baudrillard beweer nie; en tweedens veronderstel, of noodsaak die simulacrum ‘n onderliggende dualistiese wêreldbeeld ten einde geldig verklaar te kan word. Met verwysing na die gebruik van metafoor in magies realistiese tekste en visuele kuns, word die argument saamgevat deur ’n bespreking van my persoonlike kunsprojek, vernaam ’n versameling werk wat Etienne van Heerden se roman Toorberg (1986) as verwysingspunt gebruik. Die voorbeelde waarna ek verwys ondersteun my spekulatiewe filosofiese argument teen hiperrealiteit (hyperreality); hoe die simulakrale (simulacral) aard van metafoor (soos werksaam binne ’n poststrukturalistiese model van die ‘teken’) as ’n kritiese aspek van selfrefleksiewe individuele bewussyn funksioneer. Ek argumenteer vervolgens dat subjektiwiteit sigself inherent deel is van die werking van simulacrum.

The purpose of the thesis is to contribute with knowledge of preschool teachers' perceptions of working with digital imaging in image teaching. I collected the empirical material by qualitative semi-structured interviews, along with an interview-guide. The respondents were eight preschool-teachers, who works on five different preschools in the middle of Sweden. I analyzed the empirical material with research and by an analysis-model from phenomenography. The result shows that the perceptions were varied. They felt positivity to begin conduct teaching in digital imaging after the curriculum be valid July 1, 2019. / Syftet med examensarbetet är att bidra med kunskap om förskollärares uppfattningar av att arbeta med digitalt bildskapande i bildundervisningen. En kvalitativ forskningsstrategi användes, med fenomenografi som metodansats. Datainsamlingen genomfördes med hjälp av semistrukturerade intervjuer. Informanterna var åtta förskollärare, som arbetar på fem olika förskolor. Analysen av resultatet gjordes med utgångspunkt av multimodal teori och sociokulturellt perspektiv. Resultatet av frågeställningarna visar på en varierad uppfattning av arbete med digitalt bildskapande i undervisning. Resultatet visar också att användandets omfång var varierad på förskolorna. Flera förskollärare hade intresse av att öka undervisningen i digitalt bildskapande, efter den reviderade läroplanen för förskolan trätt i kraft 1 juli 2019.

Made available in DSpace on 2016-08-10T10:53:38Z (GMT). No. of bitstreams: 1 MILCIADES HEITOR DE ABREU PARDO.pdf: 4439277 bytes, checksum: ff5766d35aca3a3804289bc389bf50d5 (MD5) Previous issue date: 2012-08-20 / For proper exploitation of natural resources, it is necessary, besides the use of tools that assist in the planning of environmental activities and detailed knowledge of the region, an accurate environmental perception of those who inhabit this environment. Therefore, the aim of this paper is to propose a methodology for environmental management that helps in the understanding of processes related to conservation of natural resources with emphasis on its employees and neighboring communities. The study was carried out at Embrapa Acre with the use of direct and indirect research techniques (questionnaires), and also tools necessary for the utility of a geographic information system (GIS). To enhance the environmental perception of the communities involved two kinds of questionnaires were applied with closed and choice multiple questions. These were applied in the employees and neighboring communities levels, which resulted in a better understanding of the existing potentiality for development and the socioeconomic factors of the locality. We observed evident possibilities for the increase of the use of natural resources in the experimental field. The questionnaire results pointed and suggested practical unit developments, such as the reforestation of permanent preservation areas. These facts were corroborated by studies in the evaluation of field data collected and integrated in remote sensing. We highlighted the photointerpretation and as a result the suggestion of the adoption of a GIS by the company. Besides the theoretical emphasis, the compatibility between the use of aerial photographs and data mining was supported by softwares such as ArcGIS and made it possible the development of a database, which included the creation and development of spatial structures recognized and measured in field with the use of geographic position system (GPS). Thus, by means of experimental results obtained, the method of photointerpretation presented effective classification of the experimental field of Embrapa Acre, with elaboration of thematic maps of the area and a GIS. Allied to these techniques, the study infers the global perception of the community and employees as essential and confirms that environmental care has acquire more social and ecological sensitivity, in search of a better quality of life and sustainable development. / Para a exploração adequada dos recursos naturais é necessário, além da utilização de ferramentas que auxiliem no planejamento das atividades ambientais e do conhecimento detalhado da região, uma percepção ambiental apurada daqueles que habitam este meio. Portanto, o objetivo desse trabalho é propor uma metodologia de gestão ambiental que auxilie na compreensão dos processos relacionados à conservação dos recursos naturais, com ênfase em seus colaboradores e comunidades vizinhas. O estudo foi desenvolvido no campo experimental da Embrapa Acre com utilização de técnicas de pesquisa direta e indireta (questionários), além de ferramentas necessárias para utilização de um sistema de informação geográfica (SIG). Para acrescer a percepção ambiental das comunidades envolvidas, foram aplicados dois modelos de questionários com perguntas fechadas e de múltiplas escolhas. Estes foram aplicados nos níveis de colaboradores e das comunidades vizinhas, o que resultou uma melhor compreensão das potencialidades existentes de desenvolvimento e os fatores socioeconômicos da localidade. Observaram-se evidentes possibilidades de aumento do uso dos recursos naturais do campo experimental, como, por exemplo, o reflorestamento de áreas de preservação permanente. Este último, apoiado pelo estudo na avaliação dos dados de campo coletados e integrados no sensoriamento remoto. Destacou-se a fotointerpretação e, como resultado, a sugestão de adoção pela Empresa de um SIG. Além da ênfase teórica a compatibilidade entre o uso de fotografias aéreas e a mineração de dados, apoiou-se em softwares como o ArcGIS e tornou-se possível a elaboração de uma base de dados, que contou com a criação e elaboração de estruturas espaciais reconhecidas e aferidas no campo com auxílio de GPS Global Positioning System . Assim, por meio dos resultados experimentais obtidos, o método da fotointerpretação apresentou efetividade de classificação do campo experimental da Embrapa Acre, com elaboração de mapas temáticos da área e um SIG. Aliado a essas técnicas o estudo infere a percepção global das comunidades e colaboradores como essencial e confirma que o cuidado ambiental adquiriu maior sensibilidade social e ecológica na busca de uma melhor qualidade de vida e desenvolvimento sustentável.

This work extends the technology of amorphous silicon (a-Si) thin film transistors (TFTs) from traditional switching applications to on-pixel signal amplification for large area digital imaging and in particular, is aimed towards enabling emerging low noise, high resolution and high frame rate medical diagnostic imaging modalities such as digital tomosynthesis. A two transistor (2T) pixel amplifier circuit based on a novel charge-gate thin film transistor (TFT) device architecture is introduced to shrink the TFT based pixel readout circuit size and complexity and thus, improve the imaging array resolution and reliability of the TFT fabrication process. The high resolution pixel amplifier results in improved electrical performance such as on-pixel amplification gain, input referred noise and faster readouts. In this research, a charge-gated TFT that operates as both a switched amplifier and driver is used to replace two transistors (the addressing switch and the amplifier transistor) of previously reported three transistor (3T) APS pixel circuits.. In addition to enabling smaller pixels, the proposed 2T pixel amplifier results in better signal-to-noise (SNR) by removing the large flicker noise source associated with the switched TFT and increased pixel transconductance gain since the large ON-state resistance of the switched TFT is removed from the source of the amplifier TFT. Alternate configurations of 2T APS architectures based on source or drain switched TFTs are also investigated, compared, and contrasted to the gate switched architecture using charge-gated TFT. A new driving scheme based on multiple row resetting is introduced which combined with the on-pixel gain of the APS, offers considerable improvements in imaging frame rates beyond those feasible for PPS based pixels. The novel developed 2T APS architectures is implemented in single pixel test structures and in 88 pixel test arrays with a pixel pitch of 100 µm. The devices were fabricated using an in-house developed top-gate TFT fabrication process. Measured characteristics of the test devices confirm the performance expectations of the 2T architecture design. Based on parameters extracted from fabricated TFTs, the input referred noise is calculated, and the instability in pixel transconductance gain over prolonged operation tine is projected for different imaging frame rates. 2T APS test arrays were packaged and integrated with an amorphous selenium (a-Se) direct x-ray detector, and the x-ray response of the a-Se detector integrated with the novel readout circuit was evaluated. The special features of the APS such as non-destructive readout and voltage programmable on-pixel gain control are verified. The research presented in this thesis extends amorphous silicon pixel amplifier technology into the area of high density pixel arrays such as large area medical X-ray imagers for digital mammography tomosynthesis. It underscores novel device and circuit design as an effective method of overcoming the inherent shortcomings of the a-Si material . Although the developed device and circuit ideas were implemented and tested using a-Si TFTs, the scope of the device and circuit designs is not limited to amorphous silicon technology and has the potential to be applied to more mainstream technologies, for example, in CMOS active pixel sensor (APS) based digital cameras.

This work extends the technology of amorphous silicon (a-Si) thin film transistors (TFTs) from traditional switching applications to on-pixel signal amplification for large area digital imaging and in particular, is aimed towards enabling emerging low noise, high resolution and high frame rate medical diagnostic imaging modalities such as digital tomosynthesis. A two transistor (2T) pixel amplifier circuit based on a novel charge-gate thin film transistor (TFT) device architecture is introduced to shrink the TFT based pixel readout circuit size and complexity and thus, improve the imaging array resolution and reliability of the TFT fabrication process. The high resolution pixel amplifier results in improved electrical performance such as on-pixel amplification gain, input referred noise and faster readouts. In this research, a charge-gated TFT that operates as both a switched amplifier and driver is used to replace two transistors (the addressing switch and the amplifier transistor) of previously reported three transistor (3T) APS pixel circuits.. In addition to enabling smaller pixels, the proposed 2T pixel amplifier results in better signal-to-noise (SNR) by removing the large flicker noise source associated with the switched TFT and increased pixel transconductance gain since the large ON-state resistance of the switched TFT is removed from the source of the amplifier TFT. Alternate configurations of 2T APS architectures based on source or drain switched TFTs are also investigated, compared, and contrasted to the gate switched architecture using charge-gated TFT. A new driving scheme based on multiple row resetting is introduced which combined with the on-pixel gain of the APS, offers considerable improvements in imaging frame rates beyond those feasible for PPS based pixels. The novel developed 2T APS architectures is implemented in single pixel test structures and in 88 pixel test arrays with a pixel pitch of 100 µm. The devices were fabricated using an in-house developed top-gate TFT fabrication process. Measured characteristics of the test devices confirm the performance expectations of the 2T architecture design. Based on parameters extracted from fabricated TFTs, the input referred noise is calculated, and the instability in pixel transconductance gain over prolonged operation tine is projected for different imaging frame rates. 2T APS test arrays were packaged and integrated with an amorphous selenium (a-Se) direct x-ray detector, and the x-ray response of the a-Se detector integrated with the novel readout circuit was evaluated. The special features of the APS such as non-destructive readout and voltage programmable on-pixel gain control are verified. The research presented in this thesis extends amorphous silicon pixel amplifier technology into the area of high density pixel arrays such as large area medical X-ray imagers for digital mammography tomosynthesis. It underscores novel device and circuit design as an effective method of overcoming the inherent shortcomings of the a-Si material . Although the developed device and circuit ideas were implemented and tested using a-Si TFTs, the scope of the device and circuit designs is not limited to amorphous silicon technology and has the potential to be applied to more mainstream technologies, for example, in CMOS active pixel sensor (APS) based digital cameras.

Complex 3D digital objects are used in many domains such as animation films, scientific visualization, medical imaging and computer vision. These objects are usually represented by triangular meshes with many triangles. The simplification of those objects in order to keep them as close as possible to the original has received a lot of attention in the recent years. In this context, we propose a simplification algorithm which is focused on the accuracy of the simplifications. The mesh simplification uses edges collapses with vertex relocation by minimizing an error metric. Accuracy is obtained with the two error metrics we use: the Accurate Measure of Quadratic Error (AMQE) and the Symmetric Measure of Quadratic Error (SMQE). AMQE is computed as the weighted sum of squared distances between the simplified mesh and the original one. Accuracy of the measure of the geometric deviation introduced in the mesh by an edge collapse is given by the distances between surfaces. The distances are computed in between sample points of the simplified mesh and the faces of the original one. SMQE is similar to the AMQE method but computed in the both, direct and reverse directions, i.e. simplified to original and original to simplified meshes. The SMQE approach is computationnaly more expensive than the AMQE but the advantage of computing the AMQE in a reverse fashion results in the preservation of boundaries, sharp features and isolated regions of the mesh. For both measures we obtain better results than methods proposed in the literature.

Avec l’intégration des appareils photos dans les appareils mobiles, leur démocratisation et la réduction de la taille de l’imageur, de l’optique et de la taille pixels, les photos sont de plus en plus sujettes au flou de bougé dû aux tremblements de la main. À cette tendance s’ajoute un accroissement constaté dans l’exigence de qualité d’image de la part des utilisateurs. Pour réduire ce flou, des systèmes de stabilisation d’image ont été développés. Néanmoins ceux-ci ne permettent pas de garantir la qualité de netteté des images et souffrent parfois d’une intégration limitée. En réponse à ces limitations, ces travaux de recherche proposent, d’une part, un modèle de tremblement physiologique permettant de simuler de manière fidèle les flous de bougé et, d’autre part, une étude sur la perception visuelle du flou permettant le développement d’une métrique de qualité. Enfin des architectures de stabilisations, exploitant ces nouveaux outils, sont proposées. Ces nouvelles architectures permettent de réduire le nombre de composants externes ainsi que de garantir la netteté des images stabilisées. / With the integration of cameras in mobile devices, their democratization and the reduction of the imager’s size, the optical system dimensions and the pixels miniaturization, the photos become more and more subject to motion blur due to the hand tremor. In addition, the requirements in terms of image quality become higher and higher. Hence, in order to reduce this blur, several image stabilization systems have been developed. Nevertheless, they cannot guarantee the sharpness quality of resulting images and in some cases, they show integration difficulties. In order to overcome these limitations, the research work presented in this thesis proposes, first of all, a physiological tremor model that aims to simulate realistic camera shake and secondly, presents a study on visual perception of blur. This study enables the development of a quality metric. Finally, stabilization algorithms and architectures exploiting these new tools are presented. These new architectures reduce the number of external components and ensure sharp stabilized images.