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1
Starrett, Malin John. "Checking the facts in science : the experience of experimenting." Thesis, University of Ulster, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365940.
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Liu, Bo-zhi. "Understanding colour image : colour constancy." Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/50155/.
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Human visual system has a mechanism which ensures that the perceived colour of an object remains almost constant under varying illumination conditions, and this mechanism is called colour constancy. Electronic imaging systems such as digital cameras do not naturally have this ability. The color appearance of images of an object under different lighting conditions changes with the colour of the light sources and this can cause problems in many computer vision applications such as object recognition. To deal with this problem, many algorithms have been developed to estimate the input image’s illuminant, and then recover the intrinsic colour of the scene correctly. In this thesis, we focus on this topic, try to produce new colour constancy algorithms in both images and videos, to improve the performance of the state of the art. This thesis makes four technical contributions. First, we have developed a new image representation scheme suitable for developing learning based colour constancy algorithms; second, we introduce a new method that formulates the colour constancy problem as one that infers the illuminant class of the input image; third, we introduce a novel clustering classification colour constancy framework (the 4C method); and finally, we extend our method from still image into video processing, create a new framework to deal with the colour constancy problem in videos. As in many computer vision problems, one of the crucial issues is how to effectively represent the input events. Colour constancy is no exception and we need to first represent the input image. As we are only interested in the colours of the image, colour histogram is a natural choice. However, traditional colour histogram is content dependent. As our task is estimating the colours of the illuminant rather than the colours of the image, we need a representation that is relatively independent of the image content. Based on this reasoning, we introduce the novel concept of a binary colour histogram where it records if a colour has appeared in the image or not and disregards the frequency of the colours appear in the image. We will present experimental results to demonstrate that our new binary histogram representation is particularly suitable for learning based colour constancy and that it provides better performances than other traditional representation schemes. The colour of a digital image is directly affected by the colour of the illuminant. We reason if we can recognize or classify the illuminant source of the image, we can then correct the colour of the image. Based on this rationale, we formulate the colour constancy problem as an illuminant classification problem. We assume that each image has an associated class of illuminant and the task of colour constancy is that of recognizing the illuminant class of the image. To accomplish this, we make use of our newly introduced binary colour histogram representation scheme and employ a powerful machine learning method called the Random Forest to construct the illuminant recognition system. We will present experimental results to show the effectiveness of our new method. Encouraged by the success of our illuminant recognition framework, we have developed a novel clustering classification colour constancy (the 4C) framework. We reason that similar illuminants will result in similar white point colours in an image. Based on this assumption, we first use a clustering algorithm to group similar white point colours of the training samples into the same cluster. We then treat the images in the same cluster as belonging to the same illumination source and each cluster as one class of illuminants. The colour constancy problem, i.e., that of estimating the unknown illuminant of an image, becomes that of identifying which illuminant class (cluster) the image’s illuminant falling into. We again make use of our novel binary colour histogram representation and our random forest based illuminant classification methods to implement our new 4C colour constancy framework. We present experimental results on publicly available testing datasets and show that our new method is competitive to state of the art. As a practical application, we have successfully extended our novel colour constancy methods from still image into video processing. The video tonal stabilization problem is still an unsolved problem, and current algorithms are only focusing on keeping the tonal stable during video playing, not really trying to recover the incorrect illuminant. We tackle these two problems together by keeping the tonal stable and recovering the frame colour to a canonical illuminant. Our approach first divides video frames into shots containing similar illuminant characteristics. We then correct the frames in the same scene by using the Random Forest illuminant estimation framework. A smooth function is applied to prevent flick and flash from occurring at the boundary of the neighboring scenes. Experimental results show that our new methods can improve video quality effectively.
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Neumann, Eva-Marie. "Architecture, science and colour in Britain 1945-1976." Thesis, University College London (University of London), 1999. http://discovery.ucl.ac.uk/1382237/.
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The development of a scientific theory of colour and of standardized colour ranges by a small group of modernist architects is a fascinating but Little-known episode of post-war British architectural history. In many articles, official publications, and conferences, and from within key organizations of the building industry, these architects promoted a theory of colour selection and application based on seemingly 'functional' and 'rational' criteria such as the 'aesthetic of the structure', the character of the building and its occupants, and the improvement of lighting and vision. Architects were also concerned with the standardization of colour, leading, from 1955 until the late 1970s, to farchitectural' ranges responding to 'functional' needs being published as official British Standards. Cotour in modern architecture has only recently become the subject of critical historical studies. Its belated reassessment by historians is, in part-, related to modernism's own rejection of cotour, which was seen to belong to the transient and decadent phenomena of decoration and fashion. Yet, many modernist architects persisted in thinking about and applying colour in their buildings. This thesis explores some of the different and complex meanings of colour as well as the ambivalent role of science in post-war British architecture. It shows that the scientization and standardization of colour after the war was in part an attempt by architects to maintain and make I acceptable a new decorative theory and practice of colour in face of the dominant ideology of science promoted by the Welfare State, and of the modernist hostility to decoration. It shows that colour was then such an attractive subject for architects because it allowed them to appear as scientific experts but at the same time, retain control over architectural practice by asserting the primacy of their mysterious aesthetic abilities.
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McEwen, Gordon John. "Colour image processing for textile fibre matching in forensic science." Thesis, Queen's University Belfast, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336101.
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Eves, Bob. "The colour concept generator : a computer tool to propose colour concepts for products." Thesis, Bournemouth University, 1997. http://eprints.bournemouth.ac.uk/333/.
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This thesis documents research undertaken into the design and evaluation of a computer tool (Colour Concept Generator) to produce colour schemes for products from verbal descriptors depicting a required aesthetic image or style. The system was designed to translate between descriptive words and colour combinations and aims to provide a form of ideas stimulus for a product designer at the initial stages of the design process. The computer system uses elements of artificial intelligence (AI) to `learn' colour and descriptor semiotic relations from a product designer based upon a proposed objective criteria or to reflect a designers personal style. Colour concepts for products can then be generated from descriptors based upon these semiotic relations. The philosophy of the research is based upon the idea of computing colour aesthetics at the front end of the design process and the design of an Al software mechanism to facilitate this. The problem was analysed with respect to the available literature on colour and a set of detail requirements for the system were presented. The system was then designed and code based upon the requirements and evaluated in terms of the overall philosophy, system methodology and application of computer media. The research is a contribution to the field of computer aided design regarding colour aesthetics and demonstrates the possibility of using an artificial intelligent machine to inspire and stimulate creative human thought. The Al software mechanism of the Colour Concept Generator is presented as an application of Al to aesthetic design. 11
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Yeh, Chun-Wei. "Colour morphology and its approaches." Thesis, University of Birmingham, 2015. http://etheses.bham.ac.uk//id/eprint/5430/.
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Mathematical morphology was first applied to binary images and readily extended to grey-level images. In extending mathematical morphology to colour it is difficult to define a suitable unambiguous ordering. We present two complete ordering schemes based on colour difference and similarity ordering for colour morphology. A novel colour difference formula is first introduced. This colour difference formula is based on colour extrema derived from a simple physical model of image formation and avoids the more arbitrary mathematical and perceptual definitions previously reported. Moreover, we define similarity criteria as the basis for mathematical morphology that can be used with flat and non-flat structuring elements. The proposed orderings meet the properties of mathematical morphology, and provide a harmonised approach for binary, grey-level and colour morphology. A comparison of ordering schemes for dilation, erosion, opening, closing and filtering operator shows the colour difference-based ordering presented here to be at least as good as other ordering schemes and better than some of the well principled, previously reported methods in not generating artefacts and reducing image noise. Additionally, the development of a similarity-based ordering to perform morphological gradient and Hit-or-Miss transforms for colour images is presented.
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Nicklas, Charlotte. "Splendid hues : colour, dyes, everyday science and women's fashion, 1840-1875." Thesis, University of Brighton, 2009. https://research.brighton.ac.uk/en/studentTheses/101ff2e9-82bb-40f2-b205-d656f58d8de4.
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Great changes characterized the mid- to late nineteenth century in the field of dye chemistry, including many innovations in the production of colours across the spectrum, especially the development of synthetic dyes from coal-tar aniline. From 1840 to 1875, textile manufacturers offered a wide variety of colourful dress textiles to female fashion consumers in both Great Britain and the United States. Middle-class women were urged to educate themselves about dyeing, science, and colour, while cultivating appropriate, moderate attention to fashion in dress. This thesis examines the mid-nineteenth century relationship of fashion, dye chemistry, and everyday science, exploring consumers’ responses to these phenomena of modernity. Paying special attention to the appreciation of chemistry and colour theory during the period, this project considers how the development of new dyes affected middle-class uses and discussions of colours in women’s dress.
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Taylor, Richard Ian. "Colour object recognition using shape-based aspects." Thesis, University of Southampton, 1992. https://eprints.soton.ac.uk/361149/.
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Hediyeh, Zahabi. "Colour changing electro active polymer systems." Thesis, Queen Mary, University of London, 2017. http://qmro.qmul.ac.uk/xmlui/handle/123456789/24856.
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Dielectric elastomers are electroactive polymers, which change size and shape in response to an electrical field. Dielectric elastomer actuators (DEAs) are highly promising new technologies in optical applications such as tuneable optical lenses, diffraction gratings and active camouflage. This thesis aims to develop a new approach to create a strain actuated compliant colour changing device that is controlled using DEAs as they offer stretchability, low weight, high efficiency, low cost and the possibility for miniaturisation. Conventional DEAs use transparent elastomeric materials with no significant colour change with strain. Conversely, liquid crystal materials are known to display dynamic colour changing behaviour, thereby making them good candidate materials. The thesis examines both the potential for colour changing soft actuators and the upcoming challenges in this field as well as the key concepts around liquid crystals that exhibit colour change. An initial approach was aimed at creating colour changes using dielectric elastomer actuators that drove a masked positioner. This method showed colour change since the mask changes the colour visualisation. The second approach used polymer dispersed liquid crystals, such as a nematic liquid crystal within a reactive silicone resin. The immiscibility of these compounds resulted in a dispersion of the liquid crystal droplets in the silicone matrix. However, the optical properties could not be controlled through mechanical deformation alone and the alignment of resulting LC droplets in the PDLC films was sensitive to the substrate used to perform the actuation. The next approach used reactive cholesteric liquid crystals (CLC) instead. A thin film coating process was preferred to carefully control the film's thickness by stretching. In free standing films a planar cholesteric alignment was obtained with mesogens aligned parallel to the substrate and colour was achieved based on the selective reflection of light. A transfer print technique was introduced to combine CLC coatings with elastomeric substrates that can be stretched. However, no colour change was achieved in response to mechanical deformation primarily due to the modulus and strength mismatch between the thin film and the elastomeric susbstrate material. Finally, lightly crosslinked liquid crystal elastomers using a combination of reactive and non-reactive liquid crystals were produced that were compatible with elastomer substrate materials. In free standing films planar cholesteric alignment was obtained with mesogens aligned parallel to the substrate. Successfully a reversible colour change based on selective reflection of light was achieved in response to a mechanical deformation.
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Cielniak, Grzegorz. "People Tracking by Mobile Robots using Thermal and Colour Vision." Doctoral thesis, Örebro : Örebro universitetsbibliotek, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-1111.
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Amanatidis, Dimitrios E. "Motion estimation and segmentation of colour image sequences." Thesis, Kingston University, 2008. http://eprints.kingston.ac.uk/20300/.
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The principal objective of this thesis is to develop improved motion estimation and segmentation techniques that meet the image-processing requirements of the post¬production industry. Starting with a rigorous taxonomy of existing image segmentation techniques, we proceed by focusing on motion estimation by means of optical flow calculation. A parametric motion model based method to estimate optical flow fields on three consecutive frames is developed and tested on a number of colour real sequences. Initial estimates are robustly refined in an iterative scheme and are enhanced by colour probability distribution information to enable foreground/background segmentation in a maximum a posteriori pixel classification scheme. Experiments, . show the significant contribution of the colour part towards a well-segmented image.Additionally, a very accurate variational optical flow computation method based on brightness constancy, gradient constancy and spatiotemporal smoothness constraints is modified and implemented so that it can robustly estimate global motion over three consecutive frames. Motion is enhanced by colour evidence in a similar manner and the method adopts the same probabilistic labelling procedure. After a comparison of the two methods on the same colour sequences, a third neural network based method is implemented, which initially estimates motion by employing two twin-layer optical flow calculating Gellular Neural Networks and proceeds in a similar manner, (incorporating colour information and probabilistic ally classifying pixels), leading to similar or improved quality results with the added advantage of significantly accelerated performance. Moreover, another CNN is employed with the task of offering spatial and temporal pixel compatibility constraint support, further improving the quality of the segmented images. Weights are used to control the respective contributing terms enabling optimization of the segmentation results for each sequence individually. Finally, as a case study of CNN implementation in hardware (FPGA), the use of Handel-G, a C-like, high-level, parallel, hardware description language, is exploited to allow for rapid translation of our algorithms to efficient hardware.
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Lister, Thomas. "Simulating the colour of port wine stain skin." Thesis, University of Southampton, 2013. https://eprints.soton.ac.uk/352088/.
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Currently, laser treatments for Port Wine Stain (PWS) lesions are considered the choice therapy, but response is poor or treatments are ineffective for around half of patients. It is proposed in this thesis that improvements to the effectiveness of laser treatment can be achieved through the acquisition of estimated PWS vessel number density, depths and diameters for each individual lesion. Information regarding PWS vessel architecture is found to be contained within the colour of the lesion. Presented in this thesis is a method of extracting this information through colour measurements and the inverse application of a skin model. Colour measurements are performed on 14 participants using a Konica-Minolta CM2600d spectrophotometer employing a xenon flashlamp illumination source and an integrating sphere. Light transport is simulated through an 8 layer mathematical skin model inclusive of horizontal, pseudo-cylindrical PWS blood vessels using a new Monte Carlo programme. Within the programme, model parameters were adjusted in an iterative process and skin colour was reproduced with a mean discrepancy of 1.9% reflection for clinically normal skin (24 datasets) and 2.4% for PWS skin (25 datasets). The programme estimated anatomical properties of the measured regions of skin, yielding epidermal melanin volume fractions from 0.4% to 3.3% and mean melanosome diameters from 41 nm to 384 nm across the participant group. The response to laser treatment was assessed for 10 participants through colour measurements taken immediately before and at least 6 weeks after treatment and through expert analysis of photographs for 9 participants taken at these times. Treatment response was not found to correlate directly with the pre-treatment melanin parameters estimated by the programme. Mean depths, diameters and number densities of PWS vessels were also estimated by the programme before and after treatment. These parameters were compared to data obtained from Optical Coherence Tomography (OCT) images for 5 participants. Number densities and diameters predicted by the simulation varied by no more than 10% from the values determined by OCT for 4 and 5 out of 7 regions respectively. Mean depths predicted by the simulation did not correspond with those determined by OCT however. This may be a result of the limited contribution of deeper vessels to the colour of PWS skin. Predicted PWS parameters were compared to treatment response assessed by colour measurement for 10 participants and by photographic analysis for 9 of these. Predicted vessel number densities were not found to correspond with treatment response. Vessel diameters predicted by the simulation correlated with treatment response when compared with the pulse lengths selected for treatment. Optical coefficients derived from the skin model were used to estimate appropriate laser treatment radiant exposures at the predicted mean vessel depths and these radiant exposures corresponded strongly with the treatment response. Suggestions for improvements in the predictions of melanosome diameters through changes in the adjacent skin minimisation procedure within the programme are discussed. The apparent underestimation of PWS blood vessel number densities and mean depths (compared to biopsy studies) may be a result of the reduced influence of deeper PWS vessels upon skin colour. Further investigation, including modifications to the PWS vessel minimisation procedure within the programme, would be necessary to determine whether improvements in these predictions may be achievable. The results of the study show that the new Monte Carlo programme is capable of extracting, from measurements of skin colour, realistic estimates of PWS skin characteristics which can be used to predict treatment response and therefore inform treatment parameters on an individual PWS.
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McColl, Roderick William. "Colour image quantisation and coding for optimal perception." Thesis, University of Warwick, 1991. http://wrap.warwick.ac.uk/73515/.
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Once a digital image is processed in some way and the reconstruction is compared to the original, the final arbiter of reconstruction quality is the human to whom the images are presented. The research presented here is concerned with the development of schemes for the quantisation of colour images and for the encoding of colour images for transmission, with the goal of minimising the perceived image distortion rather than minimising a traditional error signal statistic. In order to quantise colour images with minimum perceived distortion, a colour space is sought in which Euclidean distances correspond linearly to perceived colour difference. The response of the visual system to colour and colour difference is investigated. A new quantisation scheme is developed and implemented to achieve a colour image compression ratio of approximately 6: 1. Three variations on the basic quantiser algorithm are considered and results of applying each variation to three test images are presented. Two-component encoding of colour images for low bit-rate transmission is investigated. A new method of encoding the contents of the image regions following contour extraction is developed. Rather than using parametric surface descriptions, a quad-tree is constructed and a simple measure of perceived image contrast threshold is used to determine the transmitted data. Arithmetic entropy coding is used to discard statistical redundancy in the signal . A colour wash process recreates the colour in each region. Implementation details are presented and several examples are given to illustrate differing contrast thresholds with compression rates of up to 50: 1. An analysis of the textures in certain regions of the test images leads to the development of an algorithm to synthesise the appearance of the textures following extraction of a small block which may be repeated across the region, leading to dramatic compression rates in · some instances.
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Pancholy, Rajiv. "A multiprocessor interface for a colour graphics animation system /." Thesis, McGill University, 1990. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=60110.
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This thesis describes the design and hardware implementation of a high speed multi-processor interface used in a colour graphics animation system. The design involves the use of Direct Memory Access to move data between the memories of the various CPUs constituting the Grads system. The system accommodates the various bus protocols, word sizes, and interrupt schemes of the different processors. An evaluation of the completed system is presented.
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Pharo, Gavin. "Assessment of 13 Forensic Molecular Markers for skin colour in South Africa." Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/29463.
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Molecular phenotyping is the use of informative genetic variation to estimate appearance. This concept can be applied in a forensic context to predict the appearance of suspects or decayed deceased individuals, which would otherwise remain unidentifiable. This concept has importance in a local context, as approximately 300 individuals remain unidentified, after conventional identification techniques, at Salt River Mortuary, every year. Ancestry Informative Markers (AIMs) are genetic variants with DNA which have been commonly associated with pigmentation phenotypes, and thus has value in predicting skin tone, hair colour and eye colour. This research study aimed to design and optimise an assay to genotype 13 AIMs associated with pigmentation, and then demonstrate the value of this assay by applying it to a case example and qualitatively predicting appearance. Primers were designed and PCR assays optimised to amplify each region, followed by Sanger sequencing on a case example. The case was that of an abandoned neonate, with unknown sex and ancestry. A comparison of the obtained genotypes to previous literature was performed to qualitatively estimate the skin tone, eye colour and hair colour of the decedent, which was not only in agreement with the forensic pathologist’s interpretation of sex and ethnicity, but provided richer detail with regards to ancestry, skin tone, eye colour and hair colour. The PCR assays were then further optimised into four multiplex assays with the intention of genotyping these AIMs by two SNaPshot® PCR assays (Applied Biosystems) in a larger control cohort to model the relationship between these AIMs and melanin index more objectively. Unfortunately, the scope of this research project did not allow for the completion of this additional aspect. Overall, these results indicate that these 13 AIMs have potential to predict pigmentation phenotypes of South African individuals. However, genotyping and modelling of the effects of these AIMs should be performed on a large cohort to further strengthen this conclusion.
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Badawi, Waleed Kamal Mohammed. "Investigation of colour constancy using blind signal separation and physics-based image modelling." Thesis, Staffordshire University, 2011. http://eprints.staffs.ac.uk/1878/.
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Colour is an important property in image and video processing; it is used for the segmentation, classification, and recognition of objects. The observed colour of a surface, as captured by an imaging sensor, can be affected by factors such as specular reflection, illumination variation and shadows which can lead to erroneous colour identification. This creates a need for techniques that are able to extract an illumination invariant descriptor of the surface reflectance of an object, such techniques would enable the development of image and video processing systems which are able to identify the actual colour of an object, independent of illumination variations. Thus achieving what is referred to as colour constancy. This research aims to investigate the effectiveness of applying blind signal separation integrated with a physical model of image formation into a framework for achieving colour constancy. The particular model considered in this study is the dichromatic reflection model. This model has been used in approaches to colour constancy developed by other researchers. However, most of these approaches use mixed image components (i.e. composed of specular and diffuse components) in order to estimate illumination and consequently achieve colour constancy. In addition, most of these approaches require the segmentation of the image into regions which correspond to different colours on the multi-coloured surfaces, in high specular reflection (highlight) areas of the image. Correct segmentation of multi-coloured surfaces is difficult to achieve. This thesis proposes an alternative approach embodied in a framework which integrates blind signal separation and dichromatic model of image formation. Unlike the conventional approaches, by using blind signal separation, the illumination can be estimated more accurately using the explicitly separated specular image component and colour constancy is achieved by utilising the explicitly separated diffuse image component only. In addition, by using the blind signal separation the multi-coloured surfaces segmentation problem can be avoided. The research questions addressed by this research are “how should blind signal separation be integrated with the dichromatic model?” and “how does the proposed framework perform in the context of achieving colour constancy?” A novel colour constancy framework is developed in this thesis, and experimental findings about the performance of the framework are reported. Unlike the existing work, the proposed framework includes a new method to estimate the illumination spectral power distribution (ISPD) by using an explicitly extracted specular component of images. Furthermore, the proposed framework includes a new method for estimating the surface spectral reflectance using an explicitly extracted diffuse component, instead of mixed image components which are used by other researchers. The framework consists of three stages which are: the separation of image components, the ISPD estimation and the estimation of surface spectral reflectance. The methodology exploited to evaluate the performance of the framework involves the development of algorithms, their implementation in software, and their assessment using well-designed experiments anchored on quantitative performance measurement methods. The goodness-of-fit coefficient (GFC) is used to evaluate the performance of the framework, by measuring the degree of similarity between the estimated spectral distribution and a known reference. Values of GFC range between 0 and 1; a higher value representing a higher degree of similarity. Using an image data set generated by the author, compared to the manufacturer’s specifications, the estimated ISPD has an average GFC value equal to 0.9830 and 0.9215 for two light sources with colour temperature of 5500 K and 2900 K, respectively. The average GFC of the estimated ISPD improves significantly by 2.9% when the explicit specular image component is used instead of mixed image components. Furthermore, using Foster et al’s image data set (a set of hyperspectral images of natural scenes which was collected by Foster, Nascimento, and Amano), the ISPD is estimated using the mixed image components for other light sources with different colour temperatures. The results show that the estimated ISPD has an average value of the GFC equal to 0.9986 compared to the measured illumination. Using the data set collected by the author of this thesis, the surface spectral reflectance is estimated at individual pixels of an object illuminated by two alternative light sources with colour temperatures of 5500 K and 2900 K. A comparative assessment shows that the spectral reflectance, estimated for each given surface, has almost the same spectral signature for the two light sources. The comparison between the surface spectral reflectance estimates corresponding to the two light sources gives an average GFC value which ranges from 0.9611 to 0.9887, depending on the type of the blind separation technique that is used (i.e. the spatially constrained FastICA technique and the technique developed by Umeyama and Godin). Given that the surface spectral reflectance is the output of the last stage of the framework, which depends on the output of the previous two stages, therefore the GFC measured for surface spectral reflectance reflects the performance of the whole framework. The high GFC values mean that the estimates of surface reflectance under the two light sources are very similar, despite the differences between the two illuminants. This similarity implies that the extracted surface reflectance is significantly independent of illumination characteristics, hence showing that the proposed framework achieved a significant degree of colour constancy. Moreover, the observed results show a statistically significant improvement in the accuracy of the estimated surface spectral reflectance by 2.6% in terms of average GFC value when the explicitly extracted diffuse image component is used instead of the mixed image components. Compared to the surface spectral reflectance measurements included in Foster et al’s image data set, the surface spectral reflectance estimated using the mixed image components has an average GFC value equal to 0.9608.
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Nadarajah, Kumaravel. "Computers in science teaching: a reality or dream; The role of computers in effective science education: a case of using a computer to teach colour mixing; Career oriented science education for the next millennium." Thesis, Rhodes University, 2000. http://hdl.handle.net/10962/d1003341.
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Science education in South Africa is not improving much. Many science educators do not have appropriate science qualifications. Majority of the learners have limited facilities to learn science. In this dilemma the move to OBE may result in further substantial deterioration of science education. A possible way out is to use computers in science education to facilitate the learning process. This study was designed to investigate how computers contribute to learners’ skills development in a physics course. A series of interactive computer simulations of colour mixing and a number of closely related traditional practical activities are aimed to promote learners’ understanding of colour. It was concluded that while computer environments have greater potentialas learning tools, they also limit interactions in significant ways.
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Al-Jubouri, Hanan. "Multi evidence fusion scheme for content-based image retrieval by clustering localised colour and texture features." Thesis, University of Buckingham, 2015. http://bear.buckingham.ac.uk/106/.
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Content-Based Image Retrieval (CBIR) is an automatic process of retrieving images according to their visual content. Research in this field mainly follows two directions. The first is concerned with the effectiveness in describing the visual content of images (i.e. features) by a technique that lead to discern similar and dissimilar images, and ultimately the retrieval of the most relevant images to the query image. The second direction focuses on retrieval efficiency by deploying efficient structures in organising images by their features in the database to narrow down the search space. The emphasis of this research is mainly on the effectiveness rather than the efficiency. There are two types of visual content features. The global feature represents the entire image by a single vector, and hence retrieval by using the global feature is more efficient but often less accurate. On the other hand, the local feature represents the image by a set of vectors, capturing localised visual variations in different parts of an image, promising better results particularly for images with complicated scenes. The first main purpose of this thesis is to study different types of local features. We explore a range of different types of local features from both frequency and spatial domains. Because of the large number of local features generated from an image, clustering methods are used for quantizing and summarising the feature vectors into segments from which a representation of the visual content of the entire image is derived. Since each clustering method has a different way of working and requires settings of different input parameters (e.g. number of clusters), preparations of input data (i.e. normalized or not) and choice of similarity measures, varied performance outcomes by different clustering methods in segmenting the local features are anticipated. We therefore also intend to study and analyse one commonly used clustering algorithm from each of the four main categories of clustering methods, i.e. K-means (partition-based), EM/GMM (model-based), Normalized Laplacian Spectral (graph-based), and Mean Shift (density-based). These algorithms were investigated in two scenarios when the number of clusters is either fixed or adaptively determined. Performances of the clustering algorithms in terms of image classification and retrieval are evaluated using three publically available image databases. The evaluations have revealed that a local DCT colour-texture feature was overall the best due to its robust integration of colour and texture information. In addition, our investigation into the behaviour of different clustering algorithms has shown that each algorithm had its own strengths and limitations in segmenting local features that affect the performance of image retrieval due to variations in visual colour and texture of the images. There is no algorithm that can outperform the others using either an adaptively determined or big fixed number of clusters. The second focus of this research is to investigate how to combine the positive effects of various local features obtained from different clustering algorithms in a fusion scheme aiming to bring about improved retrieval results over those by using a single clustering algorithm. The proposed fusion scheme integrates effectively the information from different sources, increasing the overall accuracy of retrieval. The proposed multi-evidence fusion scheme regards scores of image retrieval that are obtained from normalizing distances of applying different clustering algorithms to different types of local features as evidence and was presented in three forms: 1) evidence fusion using fixed weights (MEFS) where the weights were determined empirically and fixed a prior; 2) evidence fusion based on adaptive weights (AMEFS) where the fusion weights were adaptively determined using linear regression; 3) evidence fusion using a linear combination (Comb SUM) without weighting the evidences. Overall, all three versions of the multi-evidence fusion scheme have proved the ability to enhance the accuracy of image retrieval by increasing the number of relevant images in the ranked list. However, the improvement varied across different feature-clustering combinations (i.e. image representation) and the image databases used for the evaluation. This thesis presents an automatic method of image retrieval that can deal with natural world scenes by applying different clustering algorithms to different local features. The method achieves good accuracies of 85% at Top 5 and 80% at Top 10 over the WANG database, which are better when compared to a number of other well-known solutions in the literature. At the same time, the knowledge gained from this research, such as the effects of different types of local features and clustering methods on the retrieval results, enriches the understanding of the field and can be beneficial for the CBIR community.
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Lee, Pei-Ying. "Le blanc dans le cinéma de science-fiction." Thesis, Paris 1, 2018. http://www.theses.fr/2018PA01H318.
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Le blanc dans le cinéma de science-fiction vibre et scintille, comme une invitation à l’interpréter. À travers le blanc se tisse un lien entre des images sans rapports apparents, et ce type de connexion hétérogène sollicite notre regard d’une manière qui se rapproche d’un montage. Ce regard facilite de plus le détachement des figures blanches de leurs objets référentiels, du contexte du film, et même du contexte du cinéma. Dans cette vision en forme de constellation, révélant des forces liées à la construction, à la destruction et à l’incertitude, le blanc au sein du cinéma de science-fiction, de par sa nature hybride et changeante, transgresse fréquemment les lois établies de l’espace-temps. Véhiculant des sensations et des pensées variées, le blanc reflète d’une manière indirecte et fragmentaire son époque et révèle avec subtilité son passé virtuel, lequel se caractérise par une grande richesse. À la fois couleur du degré zéro et couleur intégrale, porteur de mémoire tout autant que de nouveauté, le blanc, en raison de son caractère minimal et illimité, démontre une capacité à se déplacer librement dans le monde de la science-fiction, voire d’errer dans l’univers des imagesThe colour white in the cinema of science fiction vibrates and sparkles, inviting our interpretations. Unrelated images are linked through whiteness in a form of heterogeneous connection that solicits our gaze as a montage. This look also facilitates the detachment of white figures from their reference objects, the context of the film and even the context of cinema. In this vision of a constellation, which reveals the energies of construction, destruction and uncertainty, whiteness in the cinema of science fiction by its hybrid and changing nature easily transgresses the established laws of space-time. Carrying diverse sensations and thoughts, the colour white reflects its era in a manner at once both indirect and fragmentary, discreetly revealing its virtual but rich past. At once the colour of nothingness and integrating all other colours, saturated with memory but new like a newborn, white with its minimal and unlimited character demonstrates an ability to move freely in the world of science-fiction, and even to wander in the universe of images
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Bendin, Eckhard. "Ostwalds biologische Energetik als Substrat der psychologischen Farbenlehre." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2008. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1200579355626-82806.
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Vor dem Hintergrund des heutigen Verständnisses der biologischen Psychologie zur Entstehung von Farbempfindung als selbstregulierende Energiewandlung und -wirkung wird der Beitrag gewürdigt, den Wilhelm Ostwald vor über 100 Jahren mit seiner ‚biologischen Energetik’ einbrachte. Energetische Intentionen und Interpretationen bestimmten auch dessen ,Psychologische Farbenlehre’ als das erklärte Kernstück einer modernen Farbenlehre. Obwohl im Sinne einer kritischen Rezeption auch Grenzen jener Farbenlehre aufgezeigt werden, offenbart sich aber Ostwalds energetische Konzeption durchaus als visionäre Vorleistung, die sich in vielen Aspekten mit heutigen einschlägigen Wissensbeständen deckt. Aus der Perspektive enger Beziehungen zwischen Wissenschaft und Kunst wird zudem auf befruchtende Wechselwirkungen, insbesondere die Ausstrahlung der Ostwald’schen ‚Energetik’ auf die visuellen Künste im 20. Jahrhundert hingewiesenWith today's understanding of colour perception as a self-regulating process of energy transformation and effects, biological psychology honours the contribution made by Wilhelm Ostwald over 100 years ago with his concept of ’biological energetics’. Energy considerations and interpretations determined also his ’psychological theory of colour’, the declared core of modern colour science. Even if critical reception has revealed also the limitations of this colour theory, Ostwald's energetic concept can certainly be seen as a pioneering vision, retaining its validity in many aspects in today's scientific knowledge base. In the context of close relationships between science and art, furthermore, attention must be drawn to fertile interactions, in particular in the influences of Ostwald’s ’energetics’ on the visual arts in the 20th century
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Liu, MingHui. "Navel orange blemish identification for quality grading system : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Computer Science at Massey University, Albany, New Zealand." Massey University, 2009. http://hdl.handle.net/10179/1175.
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Each year, the world’s top orange producers output millions of oranges for human consumption. This production is projected to grow by as much as 64 million in 2010 and so the demand for fast, low-cost and precise automated orange fruit grading systems is only deemed to become more increasingly important. There is however an underlying limit to most orange blemish detection algorithms. Most existing statistical-based, structural-based, model-based and transform-based orange blemish detection algorithms are plagued by the following problem: any pixels in an image of an orange having about the same magnitudes for the red, green and blue channels will almost always be classified as belonging to the same category (either a blemish or not). This however presents a big problem as the RGB components of the pixels corresponding to blemishes are very similar to pixels near the boundary of an orange. In light of this problem, this research utilizes a priori knowledge of the local intensity variations observed on rounded convex objects to classify the ambiguous pixels correctly. The algorithm has the effect of peeling-off layers of the orange skin according to gradations of the intensity. Therefore, any abrupt discontinuities detected along successive layers would significantly help identifying skin blemishes more accurately. A commercial-grade fruit inspection and distribution system was used to collect 170 navel orange images. Of these images, 100 were manually classified as good oranges by human inspection and the rest are blemished ones. We demonstrate the efficacy of the algorithm using these images as the benchmarking test set. Our results show that the system garnered 96% correctly classified good oranges and 97% correctly classified blemished oranges. The proposed system is easily customizable as it does not require any training. The fruit quality bands can be adjusted to meet the requirements set by the market standards by specifying an agreeable percentage of blemishes for each band.
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Brown, Samuel David James. "Molecular systematics and colour variation of Carpophilus species (Coleoptera: Nitidulidae) of the South Pacific." Diss., Lincoln University, 2009. http://hdl.handle.net/10182/1430.
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The sap beetle genus Carpophilus Stephens (Coleoptera: Nitidulidae) is a large genus consisting of over 200 species and are found worldwide. Several species are important pests of crops and stored products, and are frequently intercepted as part of biosecurity operations. The genus is poorly known taxonomically, and there are several species groups that are challenging to identify by morphological methods. In particular, two species found across the Pacific, C. maculatus Murray and C. oculatus Murray are frequently confused with each other. These two species are similar in size and colour, but differ primarily by the shape of the colour pattern on their elytra. However, this colour pattern is highly variable within both species, leading to ambiguity in the indentification of these species. Within C. oculatus, three subspecies have been described based on differences in the male genitalia and pronotal punctation: C. o. oculatus and C. o. gilloglyi Dobson are distributed widely across the Pacific, while C. o. cheesmani Dobson is known only from Vanuatu. A search of literature records and specimen collections revealed 32 species of Carpophilus recorded from the Pacific region. In addition there remain several unidentified specimens representing at least four species, two of which will be described subsequent to this research. A number of species recorded in the literature may have been misidentified, and these require further field collections and inspection of museum specimens to confirm their presence in the Pacific. To test the validity of the subspecies of C. oculatus, and its distinctiveness from C. maculatus, a phylogeny of available specimens of Carpophilus was inferred from one mitochondrial gene (cytochrome c oxidase subunit I (COI)), and two nuclear genes (28S ribsomal RNA (28S) and the internal transcribed spacer 2 (ITS2)). These data show large genetic distances between the three subspecies of C. oculatus of 7-12%. Given these distances are similar to those between other species in the genus, this indicates these subspecies may be elevated to full species. The data also consistently support a monophyletic relationship between C. o. oculatus and C. o. gilloglyi. Nuclear genes also support C. o. cheesmani as part of a clade with the other subspecies, but these relationships are unresolved in COI. Carpophilus maculatus was not supported as being the sister taxon of the C. o. oculatus and C. o. gilloglyi clade. Other relationships within Carpophilus were unresolved, possibly due to a combination of incomplete taxon sampling, and saturation of substitutions within the COI gene. Phylogeographic analysis of specimens collected from several localities within the range of C. oculatus showed that, with only one exception, there were no shared haplotypes between archipelagoes. This result suggests it may be possible to determine the provenence of intercepted specimens, providing further information regarding potential invasion pathways. A degree of geographic structuring was also present within C. o. gilloglyi, being separated into a western clade found in Fiji and Rotuma and an eastern clade distributed from the Kermadec Islands and Tonga to French Polynesia. This separation was most profound in COI data, with a mean pairwise distance between the clades of 7%. ITS2 data also demonstrates a degree of differentiation between the two clades, based on differences in the insertions and deletions between the clades. The variability in the shape and colour of the elytral pattern of C. oculatus was also investigated. Colour was quantified using a method based on Red-Green-Blue (RGB) colour values derived from digital photographs, while an outline analysis of the elytral pattern was conducted using elliptic Fourier analysis (EFA). Principal Components Analysis of the RGB values and EFA coefficients showed no clear separation between subspecies, nor were any trends correlated with host fruit or collection localities. Variation at all levels and all measures studied in this thesis show that this geographic region and this genus of beetles offer intruiging insights into speciation, biogeography and biological invasions. There is much scope for further research on the causes and consequences of this variation and the lives of these interesting insects.
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Alm, Kristin, and Alice Öberg. "Logotyper och företagsmärken : Att lägga märke till märkliga märken." Thesis, Mälardalen University, Department of Innovation, Design and Product Development, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-349.
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C-uppsats vars huvudsyfte var att undersöka hur stor igenkänning människor har av företagsmärken utan att logotypen finns med. Genom att arbeta med både en kvalitativ och kvantitativ metod har vi fått fram våra resultat, detta genom att våra respondenter besvarade en enkät. Våra teoretiska perspektiv kommer från en blandning av olika ämnesområden, så som psykologi och informationsdesign med fördjupningar i bland annat perception, objektsigenkänning, symbolik och färgers betydelse. Genom våra undersökningar kom vi fram till att det inte finns något enkelt svar på huruvida märken känns igen eller inte. Bland våra utvalda märken var könsbundenheten låg, och ålder har viss betydelse för igenkänningen. Detta genom att äldre respondenter hade en högre igenkänning än de yngre.
Bachelor theses with the main purpose to investigate how well people recognize corporate brands without the logotype being present. We have achieved our results by using a mixture of both qualitative and quantitative methodology, and all of our collected data has been gathered through a survey. Our theoretical perspectives come from a variety of disciplines, such as psychology and information design, including perception, object recognition, symbolism and the importance of colours. After analysing our gathered data, we feel quite confident in claiming that there are no simple answers when it comes to our abilities to recognize corporate brands. We noticed that the gender of our respondents had none or very little impact when it comes to recognition, but age on the other hand was quite a large factor. We came to the conclusion that our older respondents recognized far more corporate brands than our younger respondents.
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Wenzel, Tobias. "Enhancing the functionality of photovoltaic and photonic biointerfaces through structuration." Thesis, University of Cambridge, 2017. https://www.repository.cam.ac.uk/handle/1810/268517.
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This two-part thesis focuses on biointerfaces of two different biological systems. It specifically examines the interplay of structure and functionality in these biointerfaces. Part one studies photo-bio-electrochemically active bacteria and the strong dependence of their electrical current generation on electrode structure and pigment organisation. Part two uncovers surprising design principles of photonic structures on flower petals and presents research tools to study disordered optical systems. Biophotovoltaics (BPV) is a newly described biophysical effect in which a biofilm of photosynthetic microorganisms associated with an anode produces electrical current that can be harvested and passed through an external circuit. In this thesis-part, an experimental set-up is presented to quantitatively measure photo-electric activity of cyanobacteria in BPVs. Using this set-up, a systematic study of anode morphologies reveals that large electrode surface areas enhance photocurrents by two orders of magnitude, identifying structuration as key design criterion for bioelectrochemical interfaces. Electrodes with micrometer-sized pores allow enhanced direct contact area with bacteria, but with tested cyanobacteria this did not result in a photocurrent increase, disproving recent speculations in the literature. Furthermore, a theoretic-mathematical framework is presented to estimate light-energy utilisation in biofilms. It is detailed how pigment concentration and distribution affects the light-level dependent saturation of electron harvesting biofilms. This study brings the theory together with experiments, such as genetic modification and photo-current measurements. Part two of this thesis approaches the interaction of light and biointerface structuration from a different angle. In a significant extension of the candidate’s MPhil project, it was discovered that the disorder in natural photonic structures can be an advantage rather than a limitation in biology. With biological image analysis, optics simulations and nano-manufacturing a new photonic effect is uncovered which is iridescent but surprisingly constant in chroma. In collaboration with plant scientists, it is shown that many flowers have co-evolved disordered surface structuration that generates this bee visible colouration.
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Rossi, Michael Paul Ph D. Massachusetts Institute of Technology. "The rules of perception : American color science, 1831-1931." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/69452.
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Thesis (Ph. D. in History, Anthropology, and Science, Technology and Society (HASTS))--Massachusetts Institute of Technology, Program in Science, Technology and Society, 2011.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 365-389).
Although vision was seldom studied in Antebellum America, color and color perception became a critical field of scientific inquiry in the United States during the Gilded Age and progressive era. Through a historical investigation of color science in the United States in the late nineteenth and early twentieth centuries, I argue that attempts to scientifically measure, define, and regulate color were part of a wider program to construct a more rational, harmonious, and efficient American polity starting from one of the very baseline perceptual components of reality - the experience of color. As part of this program, I argue secondly that color science was as much a matter of prescription as description - that is, color scientists didn't simply endeavor to reveal the facts of perception and apply them to social problems, they wanted to train everyday citizens to see scientifically, and thereby create citizens whose eyes, bodies, and minds were both medically healthy and morally tuned to the needs of the modern American nation. Finally, I argue not simply that perception has a history - i.e. that perceptual practices change over time, and that, for Americans of a century ago, experiences of color sensations were not taken as given but had to be laboriously crafted - but also that this history weighs heavily upon our present day understanding of visual reality, as manifested not least of all in scientific studies of vision, language, and cognition. Employing a close reading of the archival and published sources of a range of actors including physicist Ogden Rood, semiotician Charles Peirce, logician Christine Ladd-Franklin, board game magnate Milton Bradley, and art professor Alfred Munsell, among others, this study reveals the origins of some of the most deeply-rooted conceptions of color in modern American culture.
by Michael Paul Rossi.
Ph.D.in History, Anthropology, and Science, Technology and Society (HASTS
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Kronvall, Alf. "Perceptionsanalys av tre webbplatser som använder Flash : skillnader i syn på färg och form bland kvinnliga och manliga Internetanvändare i olika åldersgrupper." Thesis, Södertörn University College, School of Communication, Technology and Design, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-340.
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Denna uppsats undersöker hur kvinnor och män i olika åldersgrupper förhåller sig till Flashapplikationer utifrån deras uppfattning om färg och form. Deltagarna som består av skolungdomar, nyexaminerade studenter och pensionärer har genom en enkät och en semistrukturerad intervjuform fått redogöra för sina intryck av Santa Marias, Eccos och Indiskas webbplatser.
Undersökningsdeltagarna identifierar Flashelementen genom deras rörelser. Deltagarna vill välja om de ska se animationer och andra applikationer skapade i Flash för att inte tappa koncentrationen från övrigt innehåll. Studenterna i undersökningen har en mer kritisk hållning till färgval, formgivning och användandet av Flash än övriga. Kvinnorna i undersökningen har en mer liberal hållning till färg och form än männen.
This essay explores how men and women in different age groups experiences Flashapplications, depending on their perception of colour and form. The participants, teenagers at a junior high school, students who just have finished their degree and senior citizens have by answering a form and by taking part in a semi structured interview been able to express their opinion of the following Scandinavian web pages: Santa Maria, Ecco and Indiska.
The participants identify the flash objects by their movements. The participants want to be able to choose weather or not to see the animations and other applications created in Flash, to avoid loosing focus on the other information the trademarks wants to express. The students have the most critical approach to colour, form and the use of Flash objects. The female participants have a more liberal approach to colour and form then the male participants.
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Hussain, Sadul Fath. "Application of pyrolysis-mass spectrometry as a rapid analytical method in food science." Thesis, University of Reading, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335921.
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Viscido, Francesca Romana. "So Long Been Dreaming: proposta di traduzione di quattro racconti di postcolonial speculative fiction." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/12701/.
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This dissertation focuses on the translation of four short stories belonging to the Postcolonial, Science Fiction and Fantasy anthology So Long Been Dreaming (SLBD), edited by Nalo Hopkinson and Uppinder Mehan.
The main objective of this thesis is to introduce the genre known as postcolonial speculative fiction to the Italian readers, not only through the translation of the stories, but also with the help of some analysis of the genre itself and its history.
The first chapter is an analysis of the various ingredients postcolonial speculative fiction is composed of, which are science fiction, fantasy and postcolonial literature itself. Through the definitions and the brief history of those three elements, the first chapter points out the necessity of introducing and dealing with postcolonial speculative fiction as an independent genre with its own tradition and dignity.
The second chapter resumes the history of science fiction written by women, showing the relevance they have always had throughout the history of SF, supporting the decision of translating only short stories written by women.
The third chapter deals with the anthology So Long Been Dreaming. After introducing the anthology itself and its editors, Nalo Hopkinson and Uppinder Mehan, the chapter goes on analyzing the four short stories selected for this dissertation, together with their authors.
The fourth chapter contains the four translations, with a brief introduction about the parameter used to select the short stories, which are: “Rachel” by Larissa Lai, “When Scarabs Multiply” by Nnedi Okorafor-Mbachu, “The Forgotten Ones” by Karin Lowachee, and “Journey into the Vortex” by Maya Khankhoje.
Last but not least, the fifth chapter contains an overlook about the history of science fiction in Italy and the characteristics of the short story, together with a comment about the translations and the choices made during this challenging and inspiring process.
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Bancroft, Senetta. "A Critical Exploration of Science Doctoral Programs: Counterstories from Underrepresented Women of Color." University of Akron / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=akron1415633379.
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Gilfoyle, Daniel. "Veterinary science and public policy at the Cape Colony, 1877-1910." Thesis, University of Oxford, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248919.
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Natanasihamani, Hariharan. "Behavior integration for Prometheus using real world ant colony algorithm." Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=121468.
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Prometheus aims to explore artificial intelligence in a controlled but flexible environment by mimicking the properties of the real world using a swarm intelligence implementation. Swarm Intelligence has been used for solving problems in the domain of self organization, complexity and collective intelligence for a group of agents. The collective behavior of the entity considered here - ants, are modeled as a decentralized and self-organized system in which the ants communicate indirectly and thrive by modifying the environment. This novel approach combines the widely established stigmergy theory with real-time fluid dynamics by using Pheromones and the Navier-Stokes equations respectively to subject the environment to natural conditions like wind, and spread and decay of smell thus making the environment more suitable to real time conditions. The chosen real-time fluid dynamics method proves to be computationally fast, robust and far more realistic than traditional approaches. Also, for evaporation, instead of choosing a random fixed value for every timestep, we take into consideration the effect of temperature, vapor pressure, wind and humidity on evaporation and consequences of that. It is hoped that this model will be a step closer to achieving results substantially closer to the real world and also, observing the changes that the aforementioned natural properties might impose on the experimental world.Le projet d'intelligence artificielle Prometheus vise à explorer, dans un environnement contrôlé mais flexible, les propriétés du monde réel sur une intelligence en essaim. L'intelligence distribuée a été utilisée afin de résoudre les problèmes dans le domaine de l'auto-organisation, la complexité et l'intelligence collective d'un groupe d'agents. Le comportement collectif de l'entité considérée, ici la fourmi, est modélisé comme un système décentralisé et auto-organisé dans lequel les fourmis communiquent indirectement et prospèrent en modifiant l'environnement. Celle nouvelle approche combine la théorie de stigmergie avec la mécanique des fluides, utilisant respectivement les phéromones et les équations de Navier-Stokes, afin de soumettre à l'environnement des conditions naturelles comme le vent ou encore la propagation et la désintégration de l'odeur. Ainsi l'environnement correspond mieux à des conditions réelles. La méthode de mécanique des fluides en temps réel choisie, s'avère être rapidement calculable, robuste et beaucoup plus réaliste que les approches traditionnelles. De plus, pour modéliser l'évaporation, au lieu de choisir une valeur aléatoire fixée pour chaque itération, nous prenons en compte l'effet de la température, de la pression de la vapeur, du vent, de l'humidité de l'évaporation et leurs conséquences. Nous pensons que ce modèle contribuera à l'obtention de résultats nettement plus proches du monde réel et à l'observation des changements que les propriétés naturelles susmentionnées pourraient imposer à l'environnement expérimental.
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Upchurch, Diane M. (Diane Marie). "Nineteenth Century Light and Color Theory: Rainbow Science in the Art of Frederic Edwin Church." Thesis, University of North Texas, 1991. https://digital.library.unt.edu/ark:/67531/metadc500448/.
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The purpose of this study was to investigate the depiction of rainbows in the art of Frederic Church in relation to mid-nineteenth century scientific developments in order to determine Church's reliance on contemporary concerns with light and color. An examination of four Church paintings with rainbows, three oil sketches, and nearly a dozen pencil drawings shows that Church's rainbow art represents a response to mid-century cultural values connecting science and art. Changes within Church's rainbow depictions occurred as the artist explored the visual representations of light, synthesizing the scientific knowledge of light and color available to him, and reconciling that information with the requirements of art.
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Burgess, Ian Bruce. "Wetting in Color." Thesis, Harvard University, 2012. http://dissertations.umi.com/gsas.harvard:10524.
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Colorimetric litmus tests such as pH paper have enjoyed wide commercial success due to their inexpensive production and exceptional ease of use. However, expansion of colorimetry to new sensing paradigms is challenging because macroscopic color changes are seldom coupled to arbitrary differences in the physical/chemical properties of a system. In this thesis I present in detail the development of Wetting in Color Technology, focusing primarily on its application as an inexpensive and highly selective colorimetric indicator for organic liquids. The technology exploits chemically-encoded inverse-opal photonic crystals to control the infiltration of fluids to liquid-specific spatial patterns, projecting minute differences in liquids’ wettability to macroscopically distinct, easy-to-visualize structural color patterns. It is shown experimentally and corroborated with theoretical modeling using percolation theory that the high selectivity of wetting, upon-which the sensitivity of the indicator relies, is caused by the highly symmetric structure of our large-area, defect-free \(SiO_2\) inverse-opals. The regular structure also produces a bright iridescent color, which disappears when infiltrated with liquid naturally coupling the optical and fluidic responses. Surface modification protocols are developed, requiring only silanization and selective oxidation, to facilitate the deterministic design of an indicator that differentiates a broad range of liquids. The resulting tunable, built-in horizontal and vertical chemistry gradients allow the wettability threshold to be tailored to specific liquids across a continuous range, and make the readout rely only on countable color differences. As wetting is a generic fluidic phenomenon, Wetting in Color technology could be suitable for applications in authentication or identification of unknown liquids across a broad range of industries. However, the generic nature of the response also ensures chemical non-specificity. It is shown that combinatorial measurements from an array of indicators add a degree of chemical specificity to the platform, which can be further improved by monitoring the drying of the inverse-opal films. While colorimetry is the central focus of this thesis, applications of this platform in encryption, fluidics and nanofabrication are also briefly explored.Engineering and Applied Sciences
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Nyqvist, Anna, and Joar Rutqvist. "The Impact of Colour Themes on Code Readability." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-255046.
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The ability to read code is an important skill in programming, and is said to be affected by the coding environment and interface. This thesis investigates the impact of colour themes on code readability, comparing dark text on a light background to light text on a dark background. An experiment was performed where participants solved code comprehension tasks while recorded using eye tracking. Results indicated no significant differences in accuracy or time between the two colour themes. Similarly, the eye tracker recordings showed no significant difference in eye movement patterns between colour themes.Läsning av källkod är en viktig färdighet inom programmering och sägs påverkas av programmeringsmiljöns gränssnitt. Denna uppsats undersöker färgtemans effekt på kodläsbarhet, genom en jämförelse mellan mörk text på ljus bakgrund och ljus text på mörk bakgrund. Ett experiment genomfördes där deltagare studerades med blickspårning då de löste kodläsningsuppgifter. Resultaten visade inga signifikanta skillnader i andel korrekta svar eller lösningstid mellan färgteman. Blickspårningsdatan indikerade inte heller någon signifikant skillnad mellan färgteman.
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Seth, Ankush. "Isoluminant color picking and its applications." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=82423.
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Color and luminance play important roles within the field of visual arts. The reason for this lies in the complexity of the human visual perception system. Our brains experience a perceptual tension when processing isoluminant fields (i.e. fields of equal luminance value) because the luminance and color processing pathways perceive the two fields differently. Skilled artists exploit this fact to great effect. This thesis looks at how isoluminance can be applied to the field of Non-Photorealistic Rendering. Specifically, this thesis makes a novel contribution to NPR by emphasizing the importance of isoluminance. It shows how isolumnant color picking can be used to improve existing NPR image filters, and to create new ones. It presents a geometric technique for isoluminant color picking and then applies it in a pointillist filter, a new Chuck Close inspired filter, and a unique image mosaic filter.
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Onelli, Olimpia Domitilla. "Complex photonic structures in nature : from order to disorder." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/273768.
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Structural colours arise from the interaction of visible light with nano-structured materials. The occurrence of such structures in nature has been known for over a century, but it is only in the last few decades that the study of natural photonic structures has fully matured due to the advances in imagining techniques and computational modelling. Even though a plethora of different colour-producing architectures in a variety of species has been investigated, a few significant questions are still open: how do these structures develop in living organisms? Does disorder play a functional role in biological photonics? If so, is it possible to say that the optical response of natural disordered photonics has been optimised under evolutionary pressure? And, finally, can we exploit the well-adapted photonic design principles that we observe in Nature to fabricate functional materials with optimised scattering response? In my thesis I try to answer the questions above: I microscopically investigate $\textit{in vivo}$ the growth of a cuticular multilayer, one of the most common colour-producing strategies in nature, in the green beetles $\textit{Gastrophysa viridula}$ showing how the interplay between different materials varies during the various life stages of the beetles; I further investigate two types of disordered photonic structures and their biological role, the random array of spherical air inclusions in the eggshells of the honeyguide $\textit{Prodotiscus regulus}$, a species under unique evolutionary pressure to produce blue eggs, and the anisotropic chitinous network of fibres in the white beetle $\textit{Cyphochilus}$, the whitest low-refractive index material; finally, inspired by these natural designs, I fabricate and study light transport in biocompatible highly-scattering materials.
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Foster, Kristi A. "Effects of Reduced Light and Elevated Temperature on the Zooxanthellae Concentrations and Diameters, Pigment Concentrations, and Colony Color of Montastrea cavernosa." NSUWorks, 2005. http://nsuworks.nova.edu/occ_stuetd/275.
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This study measured certain biological characteristics (zooxanthellae concentrations and diameters, pigment concentrations, and colony color) of Montastrea cavernosa from the outer reef (16.8 - 26.5 m) in Broward County, FL in response to reduced light and elevated temperature stresses. The low light treatment simulated a lowering of light in the summertime (possibly associated with a turbidity increase from an event such as a hurricane, ship grounding, or dredging). The high temperature treatment was set at the maximum expected anomaly (3°C above the average summer maximum) to simulate the effect of warmer than normal seawater. The combination treatment tested for synergistic effects. Zooxanthellae concentrations and cell sizes were measured microscopically. Photosynthetic pigment (chlorophyll a, chlorophyll c, peridinin, diadinoxanthin, and β-carotene) concentrations were measured by high performance liquid chromatography. Significant decreases were found in zooxanthellae and pigment concentrations due to the elevated temperature treatments. No significant changes in zooxanthellae and pigment concentrations were observed due to the low light conditions or due to interactions from the combined stresses. Zooxanthellae cell sizes-did not change significantly, regardless of treatment.
Coral color change, "bleaching", was measured by a novel RGB color analysis method. Significant decreases were found in coral color due to the elevated temperature treatments. No significant changes were observed due to the low light conditions or due to interactions from the combined stresses. These results agreed with those for zooxanthellae and pigment concentrations, indicating that RGB color analysis was an acceptable, non-destructive method to quantify coral bleaching. RGB color analysis has benefits over qualitative visual observations that include (i) the reproducibility of color values despite differences in color perception and changes in ambient lighting and (ii) comparisons of color change within variable-colored coral species (e.g. Montastrea cavernosa) and between two or more species of different colors (e.g. Acropora cervicornis and Siderastrea radians).
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Wang, Robert Yuanbo. "Practical color-based motion capture." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/64589.
Full textAbstract:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2011.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 93-101).
Motion capture systems track the 3-D pose of the human body and are widely used for high quality content creation, gestural user input and virtual reality. However, these systems are rarely deployed in consumer applications due to their price and complexity. In this thesis, we propose a motion capture system built from commodity components that can be deployed in a matter of minutes. Our approach uses one or more webcams and a color garment to track either the user's upper body or hands for motion capture and user input. We demonstrate that custom designed color garments can simplify difficult computer vision problems and lead to efficient and robust algorithms for hand and upper body tracking. Specifically, our highly descriptive color patterns alleviate ambiguities that are commonly encountered when tracking only silhouettes or edges, allowing us to employ a nearest-neighbor approach to track either the hands or the upper body at interactive rates. We also describe a robust color calibration system that enables our color-based tracking to work against cluttered backgrounds and under multiple illuminants. We demonstrate our system in several real-world indoor and outdoor settings and describe proof-of-concept applications enabled by our system that we hope will provide a foundation for new interactions in computer aided design, animation control and augmented reality.
by Robert Yuanbo Wang.
Ph.D.
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Wransky, Michael E. "True Color Measurements Using Color Calibration Techniques." University of Akron / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=akron1438966992.
Full text
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Gilbert, B. John. "Color Vision in the Bovine." DigitalCommons@USU, 1985. https://digitalcommons.usu.edu/etd/4117.
Full textAbstract:
Eight heifers were trained using operant conditioning to press a plate to receive a feed reward. Different wavelengths of light were presented as correct and incorrect stimuli. Positive and negative responses to the stimuli were registered electronically. Daily sessions of 17 minutes were conducted in a chamber with external light being excluded.
The duration of the stimulus was fixed at 17 seconds after which stimuli were randomly presented. Only presses on the plate when the correct stimulus was presented were reinforced with feed. A 75% correct choice was the criterion used as acceptable discrimination.
Ratios of correct to incorrect responses were computed. A stability of response was judged to occur when the median of these ratios over 5 days did not differ by more than .05 from the median of the ratios from the previous 5 sessions. Three colors i.e. green {535nm), red {610nm), and blue {450nm) were compared pairwise during 8 trials. Trial 7 was a repeat trial of green vs red and trial 8 was a comparison of green vs green.
Heifers gave random response to green vs green. Red was distinguished from blue by five of the heifers: 1, 2, 3, 4, and 5 at 76%, 91%, 78%, 88%, and 81% correct choice respectively. Blue was distinguished from green by three of the heifers: 1, 2, and 5 at 89%, 88%, and 85% correct choice respectively. Green was distinguished from red by three of the heifers: 1, 5, and 7 at 90%, 84%, and 85% correct choice respectively. These last discriminations we r e made in the repeat trial of green vs red after heifers failed to do so in the first trial of green vs red. Color discrimination and discrimination learning have been demonstrated by these results.
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Lee, Woo Jin Edward. "Visualizing the margins: the experiences of queer people of colour." Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=67014.
Full textAbstract:
This study incorporates a critical AOP theoretical framework in order to answer the central research question which seeks to reveal the ways in which queer people of colour conceptualize their intersecting identities and resist interlocking systems of domination. Photovoice, a community-based and visual PAR methodology, enables participants to visualize their everyday realities through photography, describe their lives through these photos and individual narratives, and through critical dialogue create themes which speak to their collective experiences. Participants spoke of how historical displacement and intersecting experiences of marginalization resulted in emotional and psychological responses which complicated their relationships to mental health. Key findings reveal the complexities of integrating a historicized trans-national identity and the contemporary effects of political and structural intersectionality on the lives of queer people of colour in Canada. By collectively conceptualizing strategies of survival and resistance, this collaborative and community-building process generated new knowledge, which will serve to inform social work policies and practices.Cette étude emploie un cadre théorique critique AOP afin de répondre à la question centrale de recherche suivante: Quelle sont les façons que les minorités sexuelles racialisées conceptualisent leurs identités intersectionnelles et comment résistent-ils aux systèmes de domination qui s'enclenchent? Photovoix est une méthode de PAR, visuelle et communautaire, qui permet aux participants de s'imaginer leurs réalités quotidiennes à travers la photographie en prenant des photos et en créant des narrations. Avec le dialogue critique, les participants ont crée des thématiques collectives. Ils ont décrit le rapport entre leur santé mentale et leur état émotionnel et psychologique résultant des effets complexes de déplacement historique et des expériences d'exclusion intersectionelles. Les résultats indiquent que les minorités sexuelles racialisées au Canada développent une identité historique et transnationale et sont enclavées par les effets politiques et structurelles de l'oppression intersectionnelle. En créant des stratégies de survivance, ce processus communautaire a produit des nouvelles connaissances qui serviront de s'informer des pratiques et des mesures politiques de travail social.
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Lögdberg, Frida. "Population dynamics in variable environments – impacts of noise colour and synchrony." Doctoral thesis, Linköpings universitet, Teoretisk Biologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-72951.
Full textAbstract:
Environmental variation is an essential part of population dynamics, and two characteristics of such variation—variance and the temporal autocorrelation termed ‘noise colour’—are essential for determining the persistence of a population. In addition, the spatial correlation of local environmental variation between habitat patches (i.e., synchrony) is equally important in subdivided populations connected via dispersal. The research underlying this thesis explored the effects of noise colour and synchrony on population dynamics. The dynamics were studied primarily in single-species models with fast or slow population responses to environmental changes, and several-species systems (i.e., food webs) with different stability properties were also considered. Populations were spatially subdivided with local dynamics in discrete patches, and patch positions were modelled either implicitly or explicitly, with different landscape configurations in the latter case. It has previously been shown that the effect of increased environmental redness on extinction risk in nonspatial models depends on population responsiveness, seen as increased and decreased risks for fast and slow responding populations, respectively. Here, increased redness of noise decreased the extinction risk for fast-responding populations (in accordance with non-spatial studies) in a simple implicit landscape model (Papers I and II). Slow-responding populations in some cases showed a raised extinction risk for intermediate noise colour values (Paper I), which does not agree with earlier results. However, increasing the spatial complexity evened out the differences that were caused by responsiveness (Papers III and IV). Thus, in general, the explicit landscape models displayed a decrease in extinction risk with increasing environmental redness regardless of whether the populations were fast or slow in responding to environmental variation. Still, fast and slow responsiveness of populations differed in relation to the following: overall levels of extinction risk (Papers I, III, and IV), synchrony of population variations (Paper II), colour of population variations (Paper II), and response to landscape structure (Papers III and IV). For fast-responding populations, the degree of synchrony of population variations was similar to the synchrony of environmental noise (Paper II). Local populations of a model organism that responded slowly to environmental variation were more synchronized than the environmental variation itself, and the largest shift between the environment and the populations was seen for intermediate red noise colours (Paper II). This indicated that dispersal-induced population synchrony could be enhanced by reddened noise. Landscape configuration proved to be important for the general levels of extinction risk. This effect was most pronounced for fast-responding populations (Papers III and IV) and became even more distinct when distance-dependent synchrony was added between the environmental variations (Paper IV). Adding explicit landscapes led to an decrease in the differences between fast- and slow-responding populations, when considering the influence of noise colour on extinction risk. Also, landscape configuration affected the importance of degree of synchrony through its impact on distances between patches, which resulted in configurations where extinction risk depended solely on noise colour. The effects on stability exerted by populations embedded in food webs were investigated in an implicit landscape model (Paper V). Three types of food webs with different properties of inherent stability all showed a decrease in stability at increased environmental variance and increased redness of environmental variation. In conclusion, the single-species models showed that the survival conditions of populations that were near extinction were improved by all of the following: decreased synchrony, reddening of noise, and aggregation of patches. The results of the web simulations indicate that we need better understanding of how findings obtained using single-species models can be used to reveal the effects of noise colour on species communities. From a management perspective, altering landscape structure may compensate for increased extinction risks caused by changed noise colour of environmental variation, which is a predicted outcome of climate change.
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Barth, Brian E. (Brian Edward). "Color gamut compression for computer printing." Thesis, Massachusetts Institute of Technology, 1989. http://hdl.handle.net/1721.1/14489.
Full textAbstract:
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1989.Includes bibliographical references (leaves 111-114).
by Brian E. Barth.
M.S.
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Skaff, Sandra. "Spectral models for color vision." Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=66750.
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This thesis introduces a maximum entropy approach to model surface reflectance spectra. A reflectance spectrum is the amount of light, relative to the incident light, reflected from a surface at each wavelength. While the color of a surface can be in 3D vector form such as RGB, CMY, or YIQ, this thesis takes the surface reflectance spectrum to be the color of a surface. A reflectance spectrum is a physical property of a surface and does not vary with the different interactions a surface may undergo with its environment. Therefore, models of reflectance spectra can be used to fuse camera sensor responses from different images of the same surface or multiple surfaces of the same scene. This fusion improves the spectral estimates that can be obtained, and thus leads to better estimates of surface colors. The motivation for using a maximum entropy approach stems from the fact that surfaces observed in our everyday life surroundings typically have broad and therefore high entropy spectra. The maximum entropy approach, in addition, imposes the fewest constraints as it estimates surface reflectance spectra given only camera sensor responses. This is a major advantage over the widely used linear basis function spectral representations, which require a prespecified set of basis functions. Experimental results show that surface spectra of Munsell and construction paper patches can be successfully estimated using the maximum entropy approach in the case of three different surface interactions with the environment. First, in the case of changes in illumination, the thesis shows that the spectral models estimated are comparable to those obtained from the best approach which computes spectral models in the literature. Second, in the case of changes in the positions of surfaces with respect to each other, interreflections between the surfaces arise. Results show that the fusion of sensor responses from interreflectionCette thèse introduit une approche par entropie maximale pour la modélisation des spectres de réflectance de surface. Un spectre de réflectance est la quantité de lumière, relative à la lumière incidente, réfléchie d'une surface à chaque longueur d'onde. Bien que la couleur d'une surface puisse prendre la forme d'un vecteur 3D tel que RGB, CMY ou YIQ, cette thèse prend le spectre de réflectance de surface comme étant la couleur d'une surface. Un spectre de réflectance est une propriété physique d'une surface et ne varie pas avec les différentes interactions que peut subir une surface avec son environnement. Par conséquent, les modèles de spectres de réflectance peuvent être utilisés pour fusionner les réponses de senseurs de caméra provenant de différentes images d'une même surface ou de multiples surfaces de la même scène. Cette fusion améliore les estimés spectraux qui peuvent être obtenus et mène donc à de meilleurs estimés de couleurs de surfaces.La motivation pour l'utilisation d'une approche par entropie maximale provient du fait que les surfaces observées dans notre environnement habituel ont typiquement un spectre large et donc à haute entropie. De plus, l'approche par entropie maximale impose le moins de contraintes puisqu'elle estime les spectres de réflectance de surface à l'aide seulement des réponses de senseurs de caméra. Ceci est un avantage majeur par rapport aux très répandues représentations spectrales par fonctions de base linéaires qui requièrent une série pré-spécifiée de fonctions de base.Les résultats expérimentaux montrent que les spectres de surface de taches de surface de Munsell et de papier de construction peuvent être estimés avec succès en utilisant l'approche par entropie maximal dans le cas de trois différentes interactions de surfaces avec l'environnement. D'abord, dans le cas de changements dans l'illumination, la t
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Lafer-Sousa, Rosa. "Color : functional organization and behavior." Thesis, Massachusetts Institute of Technology, 2019. https://hdl.handle.net/1721.1/132748.
Full textAbstract:
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Brain and Cognitive Sciences, June, 2019Cataloged from the PDF version of thesis.
Includes bibliographical references.
Color is a fundamental aspect of visual experience that confers a myriad of behavioral advantages: finding objects in cluttered scenes, recognizing familiar objects, and gleaning information about the material composition and state of objects (e.g. the edibility of fruit) and agents in the world (e.g. health or emotional status). As famously pointed out by Marr (1980), a full understanding of perception requires an analysis of the computations performed, the algorithms that carry out those computations, and the implementation of those algorithms in the physical hardware of the brain. This thesis employs psychophysical methods and functional imaging to tackle questions about human color vision at all three levels: what it is used for, how we solve the classic problem of color constancy, and how our color processing machinery is functionally organized in the brain. Chapter 1 provides a brief survey of the background to these questions. Chapter 2 describes functional MRI studies in humans that find both segregation and convergence of the processing of color and shape in the brain, as well as evidence for the homology of the color system between humans and macaques. Chapter 3 uses psychophysics and a recently discovered ambiguous color stimulus ('#theDress') to investigate the cues and assumptions used by the human visual system to constrain the classic ill-posed problem of inferring the intrinsic reflectance of an object by discounting the spectral properties of the illuminant. Specifically, these studies find evidence that color constancy is mediated by sensory, perceptual, and cognitive factors (i.e., low-level features, inferences about 3D scene geometry, prior knowledge, and attention), and provide the first evidence that human skin is a sufficient cue to infer the illuminant and bring about color constant percepts. Chapter 4 uses psychophysics to evaluate the impact of memory on the color appearance of familiar objects and faces. The study finds a novel perceptual illusion that reveals the role of memory for face color in perceptual experience and social communication, sheds light on the selective pressures for the evolution of trichromatic vision in primates, and demonstrates the powerful ability of cognition to influence perception. Taken together, these studies provide clues about the perceptual and neural mechanisms underlying our rich experience of a colorful world.
by Rosa Lafer-Sousa.
Ph. D.
Ph.D. Massachusetts Institute of Technology, Department of Brain and Cognitive Sciences
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Necaise, Rance David. "Improvements to the color quantization process." W&M ScholarWorks, 1998. https://scholarworks.wm.edu/etd/1539623933.
Full textAbstract:
The presentation of color images on devices with limited color capabilities requires a reduction in the number of colors contained in the images. Color image quantization is the process of reducing the number of colors used in an image while maintaining its appearance as much as possible. This reduction is performed using a color image quantization algorithm. The quantization algorithm attempts to select k colors that best represent the contents of the image. The original image is then recolored using the representative colors. to improve the resulting image, a dithering process can be used in place of the recoloring.;This dissertation deals with several areas of the color image quantization process. The main objective, however, is new or improved algorithms for the production of images with a better visual quality than those produced by existing algorithms while maintaining approximately the same running time. First, a new algorithm is developed for the selection of the representative color set. The results produced by the new algorithm are better both visually and quantitatively when compared to existing algorithms. Second, a new nearest-neighbor search algorithm that is based on the Locally Sorted Search algorithm is developed to reduce the time required to map the input colors to a representative color. Finally, two modifications are made to the error-diffusion dithering technique that improve the execution time. These modifications include the use of a two-weight matrix for the distribution of the error values and the presentation of a method to parallelize the error-diffusion technique. Furthermore, the analytical results of several experiments are provided to show the effectiveness each of these additions and improvements.
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Jacobs, Douglas L. "Color Calibration of Computer Display Devices." NSUWorks, 1999. http://nsuworks.nova.edu/gscis_etd/606.
Full textAbstract:
Future growth of Internet commerce offering color-dependent products will require some means of calibrating CRT viewing devices. CRT monitors vary greatly in color quality because of manual setting, internal adjustments, and viewing conditions. This research has developed a physical passive comparative calibration instrument for the purpose of determining surrounding viewing conditions and adjusting displayed images with the correct appearance compensation to display images of product with valid colors.
The development and experimentation were conducted in three stages. The first stage developed a correlation between the 8-bit colors displayed on the CRT to correlated color temperature. This information was used with data derived with the passive instrument in the second stage to build ICC color profiles containing correct viewing compensation and appearance modeling. The third stage tested the matching quality of the displayed images to pictorial images of product and other images.
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Hurlbert, Anya C. "The Computation of Color." Thesis, Massachusetts Institute of Technology, 1989. http://hdl.handle.net/1721.1/7021.
Full textAbstract:
This thesis takes an interdisciplinary approach to the study of color vision, focussing on the phenomenon of color constancy formulated as a computational problem. The primary contributions of the thesis are (1) the demonstration of a formal framework for lightness algorithms; (2) the derivation of a new lightness algorithm based on regularization theory; (3) the synthesis of an adaptive lightness algorithm using "learning" techniques; (4) the development of an image segmentation algorithm that uses luminance and color information to mark material boundaries; and (5) an experimental investigation into the cues that human observers use to judge the color of the illuminant. Other computational approaches to color are reviewed and some of their links to psychophysics and physiology are explored.
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Ignatova, Maria V. "Finding faces in color images just using hue." Thesis, McGill University, 1998. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=21572.
Full textAbstract:
The typical way of using color for face localization is simple thresholding. In contrast to this, this work explores the color histogram intersection method. Simple thresholding processes color information pixel by pixel, whereas histogram intersection operates on groups of pixels. It thus captures more information. We investigate the possibility to localize faces based only on the use of color, as opposed to the post-processing of the thresholded image, usually required with simple thresholding.A color space is sought that minimizes the variations in facial color due to races and illumination conditions. We take advantage of the CIE XYZ color space because of both its perceptual superiority to the RGB space, and because a normalization of the space takes place prior to computing hue. We choose to specify facial color using just hue and we further model it through 1D hue histograms. We compute a generalized facial color model by accumulating facial color histograms across many images.
An iterative algorithm scanning the image at multiple scales is proposed. (Abstract shortened by UMI.)
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Ryan, Suzanne Marie. "Prediction of Japanese color score." Thesis, Manhattan, Kan. : Kansas State University, 2007. http://hdl.handle.net/2097/508.
Full text