2011
Journal article
Restricted
A survey of specularity removal methods
Artusi, A., Banterle, F., Chetverikov D.The separation of reflection components is an important issue in computer graphics, computer vision and image processing. It provides useful information for the applications that need consistent object surface appearance, such as stereo reconstruction, visual recognition, tracking, objects re-illumination and dichromatic editing. In this paper we will present a brief survey of recent advances in separation of reflection components, also known as specularity (highlights) removal. Several techniques that try to tackle the problem from different points of view have been proposed so far. In this survey, we will overview these methods and we will present a critical analysis of their benefits and drawbacks.Source: Computer graphics forum (Online) 30 (2011): 2208–2230. doi:10.1111/j.1467-8659.2011.01971.x
DOI: 10.1111/j.1467-8659.2011.01971.xMetrics:
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Computer Graphics Forum | CNR ExploRA
2012
Conference article
Open Access
Dynamic range compression by differential zone mapping based on psychophysical experiments
Banterle F., Artusi A., Sikudova E., Bashford-Rogers T. E. W., Ledda P., Bloj M., Chalmers A.In this paper we present a new technique for the display of High Dynamic Range (HDR) images on Low Dynamic Range (LDR) displays. The described process has three stages. First, the input image is segmented into luminance zones. Second, the tone mapping operator (TMO) that performs better in each zone is automatically selected. Finally, the resulting tone mapping (TM) outputs for each zone are merged, generating the final LDR output image. To establish the TMO that performs better in each luminance zone we conducted a preliminary psychophysical experiment using a set of HDR images and six different TMOs. We validated our composite technique on several (new) HDR images and conducted a further psychophysical experiment, using an HDR display as reference, that establishes the advantages of our hybrid three-stage approach over a traditional individual TMO.Source: ACM Symposium on Applied Perception, pp. 39–46, Los Angeles, CA, USA, 3-4 August 2012
DOI: 10.1145/2338676.2338685Project(s): 3D-COFORM Metrics:
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vcg.isti.cnr.it | dl.acm.org | doi.org | CNR ExploRA
2013
Conference article
Unknown
Color correction for tone reproduction
Pouli T., Artusi A., Banterle F., Akyuz A. O., Seidel H., Reinhard E.High dynamic range images require tone reproduction to match the range of values to the capabilities of the display. For computational reasons as well as absence of fully calibrated imagery, rudimentary color reproduction is often added as a post processing step rather than integrated into the tone reproduction algorithm. However, in the general case this currently requires manual parameter tuning, although for some global tone reproduction operators, parameter settings can be inferred from the tone curve. We present a novel and fully automatic saturation correction technique, suitable for any tone reproduction operator, which exhibits better color reproduction than the state-of the-art and we validate its comparative effectiveness through psychophysical experimentation.Source: CIC21 - Twenty-first Color and Imaging Conference, pp. 215–220, Albuquerque, New Mexico, USA, 4-8 November 2013
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CNR ExploRA
2013
Conference article
Restricted
HDR image watermarking based on bracketing decomposition
Solachidis V., Maiorana E., Campisi P., Banterle F.The present paper proposes a novel watermarking scheme specifically designed for high dynamic range (HDR) images. The employed embedding strategy is based on a decomposition of the original HDR representation into multiple low dynamic range (LDR) images by means of a bracketing process. After having inserted the selected watermark into each LDR component, the final output is generated by combining the available contributions into a single HDR object. By exploiting some of the well studied properties of digital watermarking for standard LDR images, our approach is able to generate a watermarked HDR image visually equivalent to the original one, while allowing to detect the embedded information in both the marked HDR image and in its LDR counterpart, obtained through tone-mapping operators or by extracting a specific luminance range of interest from it. Several results obtained from an extensive set of experimental tests are reported to testify the effectiveness of the proposed scheme.Source: DSP 2013 - 18th International Conference on Digital Signal Processing, pp. 1–6, Santorini, Greece, 1-3 July 2013
DOI: 10.1109/icdsp.2013.6622687Metrics:
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doi.org | ieeexplore.ieee.org | CNR ExploRA
2011
Book
Unknown
Advanced high dynamic range imaging: theory and practice
Banterle F., Artusi A., Debattista K., Chalmers A.This book is a practical introduction to the emerging new field of High Dynamic Range Imaging that combines photography, computer vision, and computer graphics. The book provides detailed equations and Matlab code. This allows the reader to have the tools for experimenting with HDR Imaging for producing compelling images. The book is divided in the following chapters: -Introduction (a brief introduction on light, human vision, and color spaces) -HDR Pipeline (including capturing, storing formats, and HDR monitors) -Tone Mapping -Expansion Operators for Low Dynamic Range Content (Inverse/Reverse Tone Mapping) -Image-Based Lighting -Evaluation of Tone Mapping and Expansion Operators -HDR Content Compressiong (images, textures, and videos) The book provides three appendecies on the Bilateral Filter, Retinex Filters, and how to use the HDR Toolbox for Matlab.
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CNR ExploRA
2014
Conference article
Unknown
Dynamic range expansion of video sequences: a subjective quality assessment study
De Simone F., Valenzise G., Paul L., Dufaux F., Banterle F.The goal of this paper is to assess whether existing solutions to expand low dynamic range (LDR) still images to high dynamic range (HDR) displays can apply to moving pictures. To this end, we conduct a subjective quality assessment test on four state-of-the-art expansion operators, using high-quality input LDR content. Our results show that, perhaps surprisingly, no temporal artifacts, such as flickering due to global illumination changes, are introduced applying frame-based algorithms. In addition, they confirm previous studies in that operators as simple as linear expansion can yield acceptable (or even excellent) quality of the HDR video.Source: The 2nd IEEE Global Conference on Signal and Information Processing, pp. 1231–1235, Atlanta, Georgia, USA, 3-5 December 2014
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CNR ExploRA
2015
Journal article
Open Access
Photorealistic rendering of mixed reality scenes
Kronander J., Banterle F., Gardner A., Miandji E., Unger J.Photo-realistic rendering of virtual objects into real scenes is one of the most important research problems in computer graphics. Methods for capture and rendering of mixed reality scenes are driven by a large number of applications, ranging from augmented reality to visual effects and product visualization. Recent developments in computer graphics, computer vision, and imaging technology have enabled a wide range of new mixed reality techniques including methods for advanced image based lighting, capturing spatially varying lighting conditions, and algorithms for seamlessly rendering virtual objects directly into photographs without explicit measurements of the scene lighting. This report gives an overview of the state-of-the-art in this field, and presents a categorization and comparison of current methods. Our in-depth survey provides a tool for understanding the advantages and disadvantages of each method, and gives an overview of which technique is best suited to a specific problem.Source: Computer graphics forum (Print) 34 (2015): 643–665. doi:10.1111/cgf.12591
DOI: 10.1111/cgf.12591Metrics:
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Computer Graphics Forum | ISTI Repository | Publikationer från Linköpings universitet | Computer Graphics Forum | www.scopus.com | CNR ExploRA
2015
Software
Unknown
Piccante
Banterle F., Benedetti L.Piccante is a header-only C++11 open-source (MPL license v2.0) imaging library, specifically designed for High Dynamic Range (HDR) processing. Piccante is modular; this means new filters, algorithms, etc. can be added in a straightforward way to its core. Piccante is easy to use and to integrate in existing projects; to use Piccante you just need to include "piccante.hpp" in your project.
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piccantelib.net | CNR ExploRA
2015
Conference article
Open Access
Effects of display rendering on HDR image quality assessment
Zerman E., Valanzise G., De Simone F., Banterle F., Dufaux F.High dynamic range (HDR) displays use local backlight modulation to produce both high brightness levels and large contrast ratios. Thus, the display rendering algorithm and its parameters may greatly affect HDR visual experience. In this paper, we analyze the impact of display rendering on perceived quality for a specific display (SIM2 HDR47) and for a popular application scenario, i.e., HDR image compression. To this end, we assess whether significant differences exist between subjective quality of compressed images, when these are displayed using either the built-in rendering of the display, or a rendering algorithm developed by ourselves. As a second contribution of this paper, we investigate whether the possibility to estimate the true pixel-wise luminance emitted by the display, offered by our rendering approach, can improve the performance of HDR objective quality metrics that require true pixel-wise luminance as input. © (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.Source: Applications of Digital Image Processing XXXVIII, San Diego, CA, USA, 9 August 2015
DOI: 10.1117/12.2186674Metrics:
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hal.archives-ouvertes.fr | ISTI Repository | doi.org | Hyper Article en Ligne | proceedings.spiedigitallibrary.org | CNR ExploRA
2015
Conference article
Restricted
Capturing reality for computer graphics applications
Unger J., Gardner A., Larsson P., Banterle F.This course covers algorithms and tools for measuring, calibrating, and registering the information required to build models of real scenes with the intent of photo-realistic image synthesis. We focus on the pipeline, i.e. how it all its together, and practical artist-driven methods and algorithms for capturing and fusing all captured data into a VPS: a geometric 3D-model of the scene, the lighting (radiance distribution) in the scene, and information describing the materials (color, reflectance and texture) of objects within the scene so that photo-realistic renderings of virtual objects can be produced.Source: SA '15 - SIGGRAPH Asia 2015 Courses, Kobe, Japan, 2-5 November 2015
DOI: 10.1145/2818143.2818160Metrics:
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dl.acm.org | doi.org | CNR ExploRA
2016
Journal article
Open Access
Mixing tone mapping operators on the GPU by differential zone mapping based on psychophysical experiments
Banterle F., Artusi A., Sikudova E., Ledda P., Bashford-Rogers T., Chalmers A., Bloj M.In this paper, we present a new technique for displaying High Dynamic Range (HDR) images on Low Dynamic Range (LDR) displays in an efficient way on the GPU. The described process has three stages. First, the input image is segmented into luminance zones. Second, the tone mapping operator (TMO) that performs better in each zone is automatically selected. Finally, the resulting tone mapping (TM) outputs for each zone are merged, generating the final LDR output image. To establish the TMO that performs better in each luminance zone we conducted a preliminary psychophysical experiment using a set of HDR images and six different TMOs. We validated our composite technique on several (new) HDR images and conducted a further psychophysical experiment, using an HDR display as the reference that establishes the advantages of our hybrid three-stage approach over a traditional individual TMO. Finally, we present a GPU version, which is perceptually equal to the standard version but with much improved computational performance.Source: Signal processing. Image communication 48 (2016): 50–62. doi:10.1016/j.image.2016.09.004
DOI: 10.1016/j.image.2016.09.004Metrics:
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ISTI Repository | Signal Processing Image Communication | www.sciencedirect.com | CNR ExploRA
2016
Book
Unknown
Image Content Retargeting: Maintaining Color, Tone, and Spatial Consistency
Artusi A., Banterle F., Aydin T. O., Panozzo D., Sorkine-Hornung O.In recent years visual devices have proliferated, from the massive high-resolution, high-contrast screens to the tiny ones on mobile phones, with their limited dynamic range and color gamut. The wide variety of screens on which content may be viewed creates a challenge for developers. Adapting visual content for optimized viewing on all devices is called retargeting. This is the first book to provide a holistic view of the subject, thoroughly reviewing and analyzing the many techniques that have been developed for retargeting along dimensions such as color gamut, dynamic range, and spatial resolution.
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CNR ExploRA
2016
Conference article
Restricted
Forensic detection of inverse tone mapping in HDR images
Fan W., Valenzise G., Banterle F., Dufaux F.High dynamic range (HDR) imaging is attracting an increasing deal of attention in the multimedia community, yet its forensic problems have been little studied so far. This paper proposes an HDR image forensic method, which aims at differentiating HDR images created from multiple low dynamic range (LDR) images from those created from a single LDR image by inverse tone mapping. For each kind of HDR image, a Gaussian mixture model is learned. Thereafter, an HDR image forensic feature is constructed based on calculating the Fisher scores. With comparison to a steganalytic feature and a texture/facial analysis feature, experimental results demonstrate the efficiency of the proposed method in HDR image forensic classification on whole images as well as small blocks, for three inverse tone mapping methods.Source: IEEE International Conference on Image Processing, pp. 166–170, Phoenix, Arizona, USA, 25-28 September 2016
DOI: 10.1109/icip.2016.7532340Metrics:
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doi.org | Hyper Article en Ligne | ieeexplore.ieee.org | CNR ExploRA
2017
Contribution to book
Closed Access
Creating HDR video using retargeting
Banterle F., Unger J.This chapter presented an overview of two methods for augmenting SDR video sequences with HDR information in order to create HDR videos. The goal of the two methods is to fill in saturated regions in the SDR video frames by retargeting non-saturated image data from a sparse set of HDR images.Source: High Dynamic Range Video: Concepts, Technologies and Applications, edited by Chalmers, A.; Campisi, P.; Shirley, P.; Olaizola, I., pp. 45–59, 2017
DOI: 10.1016/b978-0-12-809477-8.00002-9Metrics:
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doi.org | www.sciencedirect.com | CNR ExploRA
2016
Conference article
Restricted
The HDR-video pipeline
Unger J., Banterle F., Eilertsen G., Mantiuk R.High dynamic range (HDR) video technology has gone through remarkable developments over the last few years; HDR-video cameras are being commercialized, new algorithms for color grading and tone mapping specifically designed for HDR-video have recently been proposed, and the first open source compression algorithms for HDR-video are becoming available. HDR-video represents a paradigm shift in imaging and computer graphics, which has and will continue to generate a range of both new research challenges and applications. This intermediate-level tutorial will give an in-depth overview of the full HDR-video pipeline present several examples of state-of-the-art algorithms and technology in HDR-video capture, tone mapping, compression and specific applications in computer graphics.Source: Eurographics 2016 Tutorial Program, Lisbon, Portugal, 9-13 May 2016
DOI: 10.2312/egt.20161034Metrics:
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diglib.eg.org | CNR ExploRA
2017
Book
Closed Access
Advanced high dynamic range imaging
Banterle F., Artusi A., Debattista K., Chalmers A.This book explores the methods needed for creating and manipulating HDR content. HDR is a step change from traditional imaging; more closely matching what we see with our eyes. In the years since the first edition of this book appeared, HDR has become much more widespread, moving from a research concept to a standard imaging method. This new edition incorporates all the many developments in HDR since the first edition and once again emphasizes practical tips, including the authors' popular HDR Toolbox (available on the authors' website) for MATLAB and gives readers the tools they need to develop and experiment with new techniques for creating compelling HDR content.
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www.taylorfrancis.com | CNR ExploRA
2019
Conference article
Open Access
HMD-TMO: A Tone Mapping Operator for 360 degrees HDR Images Visualization for Head Mounted Displays
Goude I., Cozot R., Banterle F.We propose a Tone Mapping Operator, denoted HMD-TMO, dedicated to the visualization of 360 degrees High Dynamic Range images on Head Mounted Displays. The few existing studies about this topic have shown that the existing Tone Mapping Operators for classic 2D images are not adapted to 360 degrees High Dynamic Range images. Consequently, several dedicated operators have been proposed. Instead of operating on the entire 360 degrees image, they only consider the part of the image currently viewed by the user. Tone mapping a part of the 360 degrees image is less challenging as it does not preserve the global luminance dynamic of the scene. To cope with this problem, we propose a novel tone mapping operator which takes advantage of both a view-dependant tone mapping that enhances the contrast, and a Tone Mapping Operator applied to the entire 360 degrees image that preserves global coherency. Furthermore, we present a subjective study to model lightness perception in a Head Mounted Display.Source: Computer Graphics International Conference (CGI 2019), pp. 216–227, Calgary, Canada, 17/06/2019 - 20/06/2019
DOI: 10.1007/978-3-030-22514-8_18Project(s): ReVeRY Metrics:
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hal.archives-ouvertes.fr | ISTI Repository | vcg.isti.cnr.it | doi.org | HAL-Rennes 1 | CNR ExploRA
2018
Journal article
Open Access
Automatic saturation correction for dynamic range management algorithms
Artusi A., Pouli T., Banterle F., Akyuz A. O.High dynamic range (HDR) images require tone reproduction to match the range of values to the capabilities of a display. For computational reasons and given the absence of fully calibrated imagery, rudimentary color reproduction is often added as a post-processing step rather than integrated into tone reproduction algorithms. In the general case, this currently requires manual parameter tuning, and can be automated only for some global tone reproduction operators by inferring parameters from the tone curve. We present a novel and fully automatic saturation correction technique, suitable for any tone reproduction operator (including inverse tone reproduction), which exhibits fewer distortions in hue and luminance reproduction than the current state-of-the-art. We validated its comparative effectiveness through subjective experiments and objective metrics. Our experiments confirm that saturation correction significantly contributes toward the perceptually plausible color reproduction of tonemapped content and would, therefore, be useful in any color-critical application.Source: Signal processing. Image communication 63 (2018): 100–112. doi:10.1016/j.image.2018.01.011
DOI: 10.1016/j.image.2018.01.011Project(s): KIOS CoE Metrics:
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ISTI Repository | ZENODO | Signal Processing Image Communication | Signal Processing Image Communication | www.sciencedirect.com | CNR ExploRA
2018
Journal article
Open Access
Fine-grained detection of inverse tone mapping in HDR images
Fan W., Valenzise G., Banterle F., Dufaux F.High dynamic range (HDR) imaging enables to capture the full range of physical luminance of a real world scene, and is expected to progressively replace traditional low dynamic range (LDR) pictures and videos. Despite the increasing HDR popularity, very little attention has been devoted to new forensic problems that are characteristic to this content. In this paper, we address for the first time such kind of problem, by identifying the source of an HDR picture. Specifically, we consider the two currently most common techniques to generate an HDR image: by fusing multiple LDR images with different exposure time, or by inverse tone mapping an LDR picture. We show that, in order to apply conventional forensic tools to HDR images, they need to be properly preprocessed, and we propose and evaluate a few simple HDR forensic preprocessing strategies for this purpose. In addition, we propose a new forensic feature based on Fisher scores, calculated under Gaussian mixture models. We show that the proposed feature outperforms the popular SPAM features in classifying the HDR image source on image blocks as small as 3 x 3, which makes our method suitable to detect composite forgeries combining HDR patches originating from different acquisition processes.Source: Signal processing (Print) 152 (2018): 178–188. doi:10.1016/j.sigpro.2018.05.028
DOI: 10.1016/j.sigpro.2018.05.028Metrics:
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Signal Processing | ISTI Repository | Signal Processing | Hyper Article en Ligne | www.sciencedirect.com | CNR ExploRA