100,118 research outputs found

    High-fidelity colour reproduction for high-dynamic-range imaging

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    The aim of this thesis is to develop a colour reproduction system for high-dynamic-range (HDR) imaging. Classical colour reproduction systems fail to reproduce HDR images because current characterisation methods and colour appearance models fail to cover the dynamic range of luminance present in HDR images. HDR tone-mapping algorithms have been developed to reproduce HDR images on low-dynamic-range media such as LCD displays. However, most of these models have only considered luminance compression from a photographic point of view and have not explicitly taken into account colour appearance. Motivated by the idea to bridge the gap between crossmedia colour reproduction and HDR imaging, this thesis investigates the fundamentals and the infrastructure of cross-media colour reproduction. It restructures cross-media colour reproduction with respect to HDR imaging, and develops a novel cross-media colour reproduction system for HDR imaging. First, our HDR characterisation method enables us to measure HDR radiance values to a high accuracy that rivals spectroradiometers. Second, our colour appearance model enables us to predict human colour perception under high luminance levels. We first built a high-luminance display in order to establish a controllable high-luminance viewing environment. We conducted a psychophysical experiment on this display device to measure perceptual colour attributes. A novel numerical model for colour appearance was derived from our experimental data, which covers the full working range of the human visual system. Our appearance model predicts colour and luminance attributes under high luminance levels. In particular, our model predicts perceived lightness and colourfulness to a significantly higher accuracy than other appearance models. Finally, a complete colour reproduction pipeline is proposed using our novel HDR characterisation and colour appearance models. Results indicate that our reproduction system outperforms other reproduction methods with statistical significance. Our colour reproduction system provides high-fidelity colour reproduction for HDR imaging, and successfully bridges the gap between cross-media colour reproduction and HDR imaging

    High-fidelity reproduction of central galaxy joint distributions with Neural Networks

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    The relationship between galaxies and haloes is central to the description of galaxy formation, and a fundamental step towards extracting precise cosmological information from galaxy maps. However, this connection involves several complex processes that are interconnected. Machine Learning methods are flexible tools that can learn complex correlations between a large number of features, but are traditionally designed as deterministic estimators. In this work, we use the IllustrisTNG300-1 simulation and apply neural networks in a binning classification scheme to predict probability distributions of central galaxy properties, namely stellar mass, colour, specific star formation rate, and radius, using as input features the halo mass, concentration, spin, age, and the overdensity on a scale of 3 h1h^{-1} Mpc. The model captures the intrinsic scatter in the relation between halo and galaxy properties, and can thus be used to quantify the uncertainties related to the stochasticity of the galaxy properties with respect to the halo properties. In particular, with our proposed method, one can define and accurately reproduce the properties of the different galaxy populations in great detail. We demonstrate the power of this tool by directly comparing traditional single-point estimators and the predicted joint probability distributions, and also by computing the power spectrum of a large number of tracers defined on the basis of the predicted colour-stellar mass diagram. We show that the neural networks reproduce clustering statistics of the individual galaxy populations with excellent precision and accuracy.Comment: 12 pages, 7 figure

    Between Air and Electricity

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    After the sound reproduction industry had claimed “perfect high fidelity” for sound recordings already at the beginning of the twentieth century, composers and sound artists challenged this perfection by tweaking microphones and loudspeakers to make them act as a musical instrument instead of a mere sound reproduction device. This book explores the instrumental use of microphones and loudspeakers in music beginning in the 1950s. The popular noise musician Merzbow, over-minimalist classic Alvin Lucier, cult instrument inventor Hugh Davies, and contemporary visual artist Lynn Pook made audible what was supposed to remain silent

    Between Air and Electricity

    Get PDF
    After the sound reproduction industry had claimed “perfect high fidelity” for sound recordings already at the beginning of the twentieth century, composers and sound artists challenged this perfection by tweaking microphones and loudspeakers to make them act as a musical instrument instead of a mere sound reproduction device. This book explores the instrumental use of microphones and loudspeakers in music beginning in the 1950s. The popular noise musician Merzbow, over-minimalist classic Alvin Lucier, cult instrument inventor Hugh Davies, and contemporary visual artist Lynn Pook made audible what was supposed to remain silent

    The Color Splitting System for TV Cameras - XYZ Prism

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    One of the dominant aspects, which prejudices the quality of color image reproduction, is the first operation in TV chain - scanning. Up to this day, the color splitting system, working in RGB colorimetric system, is still entirely used. The existence of negative parts of the color matching functions r(l), g(l), b(l) causes complications by optical separation of partial pictures R, G, B in classic scanning system. It leads to distortion of reproduction of color images. However, the specific technical and scientific applications, where the color carries the substantial part of information (cosmic development, medicine), demand high fidelity of color reproduction. This article submits the results of the design of the color splitting system working in XYZ colorimetric system (next only XYZ prism). Shortly the way to obtain theoretical spectral reflectances of partial filters of XYZ prism is described. Further, these filters are approximated by real optical interference filters and the geometry of XYZ prism is established. Finally, the results of the colorimetric distortion test of proposed scanning system are stated

    Use of the Vandercook Proof Press to Predict Rotogravure Print Quality

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    The object of this thesis is to investigate a new idea in predicting printability for rotogravure printing. Present proof presses in the gravure industry are clumsy, expensive, and in most cases, impractical for regular use. In order to understand the relationship between ink, paper, and plate, it is necessary to consider many variables such as smoothness, ink receptivity, porosity, moisture content, formation, surface strength, and opacity. The laboratory work performed and presented in this paper shows that a Vandercook proof press may be used to predict printability in the gravure process

    Finding a Mate With No Social Skills

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    Sexual reproductive behavior has a necessary social coordination component as willing and capable partners must both be in the right place at the right time. While there are many known social behavioral adaptations to support solutions to this problem, we explore the possibility and likelihood of solutions that rely only on non-social mechanisms. We find three kinds of social organization that help solve this social coordination problem (herding, assortative mating, and natal philopatry) emerge in populations of simulated agents with no social mechanisms available to support these organizations. We conclude that the non-social origins of these social organizations around sexual reproduction may provide the environment for the development of social solutions to the same and different problems.Comment: 8 pages, 5 figures, GECCO'1

    Using the TIDieR checklist to standardize the description of a functional strength training intervention for the upper limb after stroke

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    Background and Purpose: Published reports of intervention in randomized controlled trials are often poorly described. The Template for Intervention Description and Replication (TIDieR) checklist has been recently developed to improve the reporting of interventions. The aim of this article is to describe a therapy intervention used in the stroke rehabilitation trial, "Clinical Efficacy of Functional Strength Training for Upper Limb Motor Recovery Early After Stroke: Neural Correlates and Prognostic Indicators" (FAST-INdICATE), using TIDieR. Methods: The functional strength training intervention used in the FAST-INdICATE trial was described using TIDieR so that intervention can be replicated by both clinicians, who may implement it in practice, and researchers, who may deliver it in future research. The usefulness of TIDieR in the context of a complex stroke rehabilitation intervention was then discussed. Results and Discussion: The TIDieR checklist provided a systematic way of describing a treatment intervention used in a clinical trial of stroke rehabilitation. Clarification is needed regarding several aspects of the TIDieR checklist, including in which section to report about the development of the intervention in pilot studies, results of feasibility studies; overlap between training and procedures for assessing fidelity; and where to publish supplementary material so that it remains in the public domain. Summary: TIDieR is a systematic way of reporting the intervention delivered in a clinical trial of a complex intervention such as stroke rehabilitation. This approach may also have value for standardizing intervention in clinical practice. Video abstract is available for more insights from the authors (see Supplemental Digital Content 1, http://links.lww.com/JNPT/A131)
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