Tone Mapping Based on Natural Image Statistics and Visual Perception Models PDF Download

Author: Praveen Cyriac
Publisher:
ISBN:
Category :
Languages : en
Pages : 184

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Book Description
Les tècniques d'imatge d'alt rang dinàmic (HDR) potencialment permeten la captura i l'emmagatzematge de tota la informació de llum en una escena. No obstant això, els dispositius comuns de visualització són limitats en termes de les seves capacitats de contrast i brillantor, per tant, les imatges HDR han de ser mapejades tonalment abans de presentar-les en un dispositiu de visualització per assegurar que es reprodueix l'aspecte original de l'escena. En aquesta tesi, es prenen dos enfocaments del problema de mapeig tonal. En primer lloc, es desenvolupa un marc general per a la millora de qualsevol imatge mapejada tonalment mitjançant la reducció de la distància a la corresponent imatge HDR en termes d'una mètrica perceptiva no local. La distància es redueix al mínim per mitjà d'un algoritme de descens de gradient. En segon lloc, es desenvolupa un operador de mapeig tonal (TMO) en temps real que s'adapta bé a les estadístiques d'escenes naturals, i concorda amb els nous descobriments psicofísics i dades neurofísiques. Determinem les correctes adaptacions no lineals necessàries per als nostres resultats de mapeig tonal per tal d'obtenir l'aparença òptima en diferents condicions de visualització, a través d'experiments psicofísics i desenvolupar un mètode automàtic per poder predir dades experimentals. El nostre TMO produeix resultats d'aspecte natural, sense cap tipus d'artefactes espacials o temporals. Els tests de preferència dels usuaris mostren que el nostre mètode obté millors resultats en comparació amb les tècniques més recents. El TMO és ràpid i podria ser implementat en el hardware de la càmera. Pot ser utilitzat per al monitoratge de càmeres HDR en pantalles regulars, com a substitut de la correcció gamma, i com una manera de proporcionar al colorista amb contingut que té alhora un aspecte natural i una aparença nítida i clara.

Author: Marcelo Bertalmío
Publisher: Academic Press
ISBN: 0128138955
Category : Computers
Languages : en
Pages : 324

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Book Description
To enhance the overall viewing experience (for cinema, TV, games, AR/VR) the media industry is continuously striving to improve image quality. Currently the emphasis is on High Dynamic Range (HDR) and Wide Colour Gamut (WCG) technologies, which yield images with greater contrast and more vivid colours. The uptake of these technologies, however, has been hampered by the significant challenge of understanding the science behind visual perception. Vision Models for High Dynamic Range and Wide Colour Gamut Imaging provides university researchers and graduate students in computer science, computer engineering, vision science, as well as industry R&D engineers, an insight into the science and methods for HDR and WCG. It presents the underlying principles and latest practical methods in a detailed and accessible way, highlighting how the use of vision models is a key element of all state-of-the-art methods for these emerging technologies. Presents the underlying vision science principles and models that are essential to the emerging technologies of HDR and WCG Explores state-of-the-art techniques for tone and gamut mapping Discusses open challenges and future directions of HDR and WCG research

Author: Gabriel Cristobal
Publisher: John Wiley & Sons
ISBN: 3527680497
Category : Technology & Engineering
Languages : en
Pages : 480

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Book Description
As the state-of-the-art imaging technologies became more and more advanced, yielding scientific data at unprecedented detail and volume, the need to process and interpret all the data has made image processing and computer vision increasingly important. Sources of data that have to be routinely dealt with today's applications include video transmission, wireless communication, automatic fingerprint processing, massive databanks, non-weary and accurate automatic airport screening, robust night vision, just to name a few. Multidisciplinary inputs from other disciplines such as physics, computational neuroscience, cognitive science, mathematics, and biology will have a fundamental impact in the progress of imaging and vision sciences. One of the advantages of the study of biological organisms is to devise very different type of computational paradigms by implementing a neural network with a high degree of local connectivity. This is a comprehensive and rigorous reference in the area of biologically motivated vision sensors. The study of biologically visual systems can be considered as a two way avenue. On the one hand, biological organisms can provide a source of inspiration for new computational efficient and robust vision models and on the other hand machine vision approaches can provide new insights for understanding biological visual systems. Along the different chapters, this book covers a wide range of topics from fundamental to more specialized topics, including visual analysis based on a computational level, hardware implementation, and the design of new more advanced vision sensors. The last two sections of the book provide an overview of a few representative applications and current state of the art of the research in this area. This makes it a valuable book for graduate, Master, PhD students and also researchers in the field.

Author: Fouad Sabry
Publisher: One Billion Knowledgeable
ISBN:
Category : Computers
Languages : en
Pages : 98

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Book Description
What is Tone Mapping Tone mapping is a technique used in image processing and computer graphics to map one set of colors to another to approximate the appearance of high-dynamic-range (HDR) images in a medium that has a more limited dynamic range. Print-outs, CRT or LCD monitors, and projectors all have a limited dynamic range that is inadequate to reproduce the full range of light intensities present in natural scenes. Tone mapping addresses the problem of strong contrast reduction from the scene radiance to the displayable range while preserving the image details and color appearance important to appreciate the original scene content. How you will benefit (I) Insights, and validations about the following topics: Chapter 1: Tone_mapping Chapter 2: Gamma_correction Chapter 3: Multi-exposure_HDR_capture Chapter 4: High-dynamic-range_rendering Chapter 5: Shadow_and_highlight_enhancement Chapter 6: High_dynamic_range Chapter 7: Tone_reproduction Chapter 8: Luminance_HDR Chapter 9: Aurora_HDR Chapter 10: EasyHDR (II) Answering the public top questions about tone mapping. (III) Real world examples for the usage of tone mapping in many fields. Who this book is for Professionals, undergraduate and graduate students, enthusiasts, hobbyists, and those who want to go beyond basic knowledge or information for any kind of Tone Mapping.

Author: Adam Kirk
Publisher:
ISBN:
Category :
Languages : en
Pages : 104

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Book Description
We present a perceptually based algorithm for modeling the color shift that occurs for human viewers in low-light scenes. Known as the Purkinje effect, this color shift occurs as the eye transitions from photopic, cone-mediated vision in well-lit scenes to scotopic, rod-mediated vision in dark scenes. At intermediate light levels vision is mesopic with both the rods and cones active. Although the rods have a spectral response distinct from the cones, they still share the same neural pathways. As light levels decrease and the rods become increasingly active they cause a perceived shift in color. We model this process so that we can compute perceived colors for mesopic and scotopic scenes from spectral data. While our tone mapping operator works with spectral data from any source, we show how to produce spectral data of static scenes using multiple images and a camera with known spectral sensitivity. If the spectral sensitivity isn't provided by the camera manufacturer, we describe a one-time calibration procedure to estimate the sensitivity. Should obtaining spectral data of a scene be infeasible, we also describe how the effect can be approximated from high dynamic range RGB images by learning a mapping from RGB to rod and cone responses. Once we have determined rod and cone responses either directly or through our approximation process, we map them to RGB values that can be displayed on a standard monitor to elicit the same color perception when viewed photopically. Our tone mapping method focuses on computing the color shift associated with low-light conditions and leverages current HDR techniques to control the image dynamic range. We include results generated from both spectral and RGB images as well as experimental data.

Author: Renu Rameshan
Publisher: Springer
ISBN: 9811300208
Category : Computers
Languages : en
Pages : 570

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Book Description
This book constitutes the refereed proceedings of the 6th National Conference on Computer Vision, Pattern Recognition, Image Processing, and Graphics, NCVPRIPG 2017, held in Mandi, India, in December 2017. The 48 revised full papers presented in this volume were carefully reviewed and selected from 147 submissions. The papers are organized in topical sections on video processing; image and signal processing; segmentation, retrieval, captioning; pattern recognition applications.

Author: Mohamed Kamel
Publisher: Springer
ISBN: 3642215939
Category : Computers
Languages : en
Pages : 467

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Book Description
The two-volume set LNCS 6753/6754 constitutes the refereed proceedings of the 8th International Conference on Image and Recognition, ICIAR 2011, held in Burnaby, Canada, in June 2011. The 84 revised full papers presented were carefully reviewed and selected from 147 submissions. The papers are organized in topical sections on image and video processing; feature extraction and pattern recognition; computer vision; color, texture, motion and shape; tracking; biomedical image analysis; biometrics; face recognition; image coding, compression and encryption; and applications.

Author: Phillip A. Laplante
Publisher: CRC Press
ISBN: 1351032739
Category : Technology & Engineering
Languages : en
Pages : 856

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Book Description
The Encyclopedia of Image Processing presents a vast collection of well-written articles covering image processing fundamentals (e.g. color theory, fuzzy sets, cryptography) and applications (e.g. geographic information systems, traffic analysis, forgery detection). Image processing advances have enabled many applications in healthcare, avionics, robotics, natural resource discovery, and defense, which makes this text a key asset for both academic and industrial libraries and applied scientists and engineers working in any field that utilizes image processing. Written by experts from both academia and industry, it is structured using the ACM Computing Classification System (CCS) first published in 1988, but most recently updated in 2012.

Author: Tania Pouli
Publisher: CRC Press
ISBN: 1568817258
Category : Computers
Languages : en
Pages : 374

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Book Description
To achieve the complex task of interpreting what we see, our brains rely on statistical regularities and patterns in visual data. Knowledge of these regularities can also be considerably useful in visual computing disciplines, such as computer vision, computer graphics, and image processing. The field of natural image statistics studies the regularities to exploit their potential and better understand human vision. With numerous color figures throughout, Image Statistics in Visual Computing covers all aspects of natural image statistics, from data collection to analysis to applications in computer graphics, computational photography, image processing, and art. The authors keep the material accessible, providing mathematical definitions where appropriate to help readers understand the transforms that highlight statistical regularities present in images. The book also describes patterns that arise once the images are transformed and gives examples of applications that have successfully used statistical regularities. Numerous references enable readers to easily look up more information about a specific concept or application. A supporting website also offers additional information, including descriptions of various image databases suitable for statistics. Collecting state-of-the-art, interdisciplinary knowledge in one source, this book explores the relation of natural image statistics to human vision and shows how natural image statistics can be applied to visual computing. It encourages readers in both academic and industrial settings to develop novel insights and applications in all disciplines that relate to visual computing.

Author: Jose H. Espina-Hernandez
Publisher: BoD – Books on Demand
ISBN: 9533070986
Category : Computers
Languages : en
Pages : 206

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Book Description
Vision Sensors and Edge Detection book reflects a selection of recent developments within the area of vision sensors and edge detection. There are two sections in this book. The first section presents vision sensors with applications to panoramic vision sensors, wireless vision sensors, and automated vision sensor inspection, and the second one shows image processing techniques, such as, image measurements, image transformations, filtering, and parallel computing.