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Item Stereo from Shading(The Eurographics Association, 2015) Chapiro, Alexandre; O'Sullivan, Carol; Jarosz, Wojciech; Gross, Markus; Smolic, Aljoscha; Jaakko Lehtinen and Derek NowrouzezahraiWe present a new method for creating and enhancing the stereoscopic 3D (S3D) sensation without using the parallax disparity between an image pair. S3D relies on a combination of cues to generate a feeling of depth, but only a few of these cues can easily be modified within a rendering pipeline without significantly changing the content. We explore one such cue-shading stereopsis-which to date has not been exploited for 3D rendering. By changing only the shading of objects between the left and right eye renders, we generate a noticeable increase in perceived depth. This effect can be used to create depth when applied to flat images, and to enhance depth when applied to shallow depth S3D images. Our method modifies the shading normals of objects or materials, such that it can be flexibly and selectively applied in complex scenes with arbitrary numbers and types of lights and indirect illumination. Our results show examples of rendered stills and video, as well as live action footage.Item 3-D Digital Preservation of At-Risk Global Cultural Heritage(The Eurographics Association, 2016) Lercari, Nicola; Shulze, Jurgen; Wendrich, Willeke; Porter, Benjamin; Burton, Margie; Levy, Thomas E.; Chiara Eva Catalano and Livio De LucaRecent current events have dramatically highlighted the vulnerability of the world's material cultural heritage. The 3-D Digital Preservation of At-Risk Global Cultural Heritage project, led by Thomas Levy at UC San Diego, catalyzes a collaborative research effort by four University of California campuses (San Diego, Berkeley, Los Angeles and Merced) to use cyberarchaeology and computer graphics for cultural heritage to document and safeguard virtually some of the most at-risk heritage objects and places. Faculty and students involved in this project are conducting path-breaking archaeological research - covering more than 10,000 years of culture and architecture - in Cyprus, Greece, Egypt, Ethiopia, Israel, Jordan, Morocco, Turkey, and the United States. This project uses the 3-D archaeological data collected in numerous at-risk heritage places to study, forecast, and model the effects of human conflict, climate change, natural disasters and technological and cultural changes on these sites and landscapes. The greater challenge undertaken by this project is to integrate archaeological heritage data and digital heritage data using the recently-announced Pacific Research Platform (PRP) and its 10-100Gb/s network as well as virtual reality kiosks installed in each participating UC campus. Our aim is to link UC San Diego and the San Diego Supercomputer Center to other labs, libraries and museums at the other UC campuses to form a highly-networked collaborative platform for curation, analysis, and visualization of 3D archaeological heritage data.Item Tutbury Castle : Recovering a period site(The Eurographics Association, 2013) Inman, Laurence; Morris, Phil; -This paper proposes a method for virtual reconstruction of a ruin in three dimensions, using a number of sources. The case study that accompanies this paper shows an example of the virtual restoration of Tutbury castle in Staffordshire UK which aims to represent it as accurately as possible following previous studies on the history of the castle and archaeological digs. Autodesk Maya is used to assemble the reconstruction of the castle and try out theories where more ambiguous sources replace primary evidence, this is then rendered in Epic's UDK game engine, then displayed in a video fly-through as well as a format suitable for viewing on a website. The project successfully recreates Tutbury Castle's past architecture more accurately than previous representations using ambiguous sources including period paintings, period floor plans, archeological and topological as well as written first hand description as evidence. This could easily be repeated on other ruins with the same successful results, creating a visual documentary of the country's heritage. Using evidence from a number of sources Using 3D games technology to bring evidence together in a realistic, efficient and controllable manner.Item Portrait Sculptures of Augustus: Categorization via Local Shape Comparison(The Eurographics Association, 2013) Lu, Min; Zhang, Yujin; Zheng, Bo; Masuda, Takeshi; Ono, Shintaro; Oishi, Takeshi; Sengoku-Haga, Kyoko; Ikeuchi, Katsushi; -3D shape comparison with digital copies draws increasing attention in modern culture heritage studies. In this paper, we focus on analyzing portrait sculptures of Augustus with 3D scanned data. A feasible framework of automatic object categorization is proposed based on shape comparison, where distinguishing regions are simultaneously detected as well. High coincidence between our result and previous archaeological speculations is observed in validation experiments, which confirms the validity of the proposed method.Item MTV-Player: Interactive Spatio-Temporal Exploration of Compressed Large-Scale Time-Varying Rectilinar Scalar Volumes(The Eurographics Association, 2019) DÃaz, Jose; Marton, Fabio; Gobbetti, Enrico; Agus, Marco and Corsini, Massimiliano and Pintus, RuggeroWe present an approach for supporting fully interactive exploration of massive time-varying rectilinear scalar volumes on commodity platforms. We decompose each frame into a forest of bricked octrees. Each brick is further subdivided into smaller blocks, which are compactly approximated by quantized variable-length sparse linear combinations of prototype blocks stored in a data-dependent dictionary learned from the input sequence. This variable bit-rate compact representation, obtained through a tolerance-driven learning and approximation process, is stored in a GPU-friendly format that supports direct adaptive streaming to the GPU with spatial and temporal random access. An adaptive compression-domain renderer closely coordinates off-line data selection, streaming, decompression, and rendering. The resulting system provides total control over the spatial and temporal dimensions of the data, supporting the same exploration metaphor as traditional video players. Since we employ a highly compressed representation, the bandwidth provided by current commodity platforms proves sufficient to fully stream and render dynamic representations without relying on partial updates, thus avoiding any unwanted dynamic effects introduced by current incremental loading approaches. Moreover, our variable-rate encoding based on sparse representations provides high-quality approximations, while offering real-time decoding and rendering performance. The quality and performance of our approach is demonstrated on massive time-varying datasets at the terascale, which are nonlinearly explored at interactive rates on a commodity graphics PC.Item Multi-scalar 3D digitization of Cultural Heritage using a low-cost integrated approach(The Eurographics Association, 2013) Manferdini, Anna Maria; Russo, Michele; -In the architectural survey field, one of the main aspects to consider during a 3D digitization is the multi-scalar geometrical complexity of the artifact to acquire, besides other fundamental factors connected with the different aims of communication. Since the widespread of range-sensors has provided extremely versatile instruments able to easily acquire huge amount of data that can be processed for different uses and users and changing communication aims, the possibility to survey and restore high-quality 3D multi-resolution models has become an urgent need. Despite these developments, these technologies are still very expensive, need expertise and present persistent bottlenecks both in the reverse modeling process and in time consuming. In order to overcome these critical aspects and taking advantage of recent improvements of automated image-based technologies based on the Structure from Motion approach, this contribution presents some first results of investigations on the reliability of these low-cost technologies for the 3D digitization of Cultural Heritage. One of the main aims of these investigations rely on developing a procedure that could ease the work of surveyors called to represent artifacts at an architectural scale using fast and low-cost technologies. 3D models derived using the selected low-cost image-based technologies were compared among each other and with a 3D laser scanner gold standard acquisition. These investigations led to qualitative and quantitative evaluations and to considerations on times and skills required by all tested technologies. Strengths and weaknesses are highlighted, suggesting the best solution with respect to the optimization of all considered aspects. Finally, integration of different technologies are presented, as it represents the best solution in multi-scalar contexts.Item Using Webcams for Product Presentations in HTML5(The Eurographics Association, 2013) Borg, Mathias; Kraus, Martin; Miguel Chover and A. Augusto de SousaThe Media Capture and Streams API ("getUserMedia API") enables plug-in free webcam support in HTML5. This opens new ways of interacting with visualisations using open web standards. In this work, two techniques are proposed that employ the user's webcam for interactive product presentations on websites. The first technique tracks the user's face and uses its position to create the impression of a user-controlled rotation of a product by displaying a sequence of product images for different view points. The second technique uses photographs of a product with reflections of coloured patterns to render the user's webcam stream as a reflection in the product presentation. Thus, users in front of a webcam are able to see their virtual reflection in a picture of a real product in real time. Our implementation of two prototypes shows that it is technically possible to implement these features with HTML5 and JavaScript only.Item Improving the digitization of shape and color of 3D artworks in a cluttered environment(The Eurographics Association, 2013) Bettio, Fabio; Gobbetti, Enrico; Merella, Emilio; Pintus, Ruggero; -We propose an approach for improving the digitization of shape and color of 3D artworks in a cluttered environment using 3D laser scanning and flash photography. In order to separate clutter from acquired material, semi-automated methods are employed to generate masks for segment the 2D range maps and the color photographs, removing unwanted 3D and color data prior to 3D integration. Sharp shadows generated by flash acquisition are trivially handled by this masking process, and color deviations introduced by the flash light are corrected at color blending time by taking into account the object geometry. The approach has been applied to, and evaluated on, a large scale acquisition campaign of the Mont'e Prama complex, an extraordinary collection of stone fragments from the Nuragic era, depicting larger-than-life archers, warriors, boxers, as well as small models of prehistoric nuraghe (cone-shaped stone towers). The acquisition campaign has covered 36 statues mounted on metallic supports, acquired at 0.25mm resolution, resulting in over 6200 range scans (over 1.3G valid samples) and 3426 10Mpixel photographs.Item ''It''+''I'': Virtual Embodiments as Hybrid Experiences(The Eurographics Association, 2013) Giraud, Tom; Paljic, Alexis; Leroy, Laure; Betty Mohler and Bruno Raffin and Hideo Saito and Oliver StaadtA dichotomy exists in the way virtual embodiments are currently studied: embodied entities are considered by conversational approaches as other selves whereas avatar approaches study them as users' hosts. Virtual reality applications such as in our case study often propose a different, in between embodiment experience. In the context of a virtual house for sale visit, this paper aims at examining the user's self-reported embodiment perception resulting from such a hybrid experience. To induce variability in this embodiment experience, we manipulated avatar representations (high versus low anthropomorphism) and frame of reference (egocentric versus exocentric). Results show the importance of the entity humanness to foster both experiences. When controlled by humanness, having a conversational experience appears uncorrelated to an avatar experience. This highlights the need to study these hybrid experiences as a combination of both approaches.Item Replicating perishable artefacts. A project for analysis and exhibition of Early Medieval objects from the Byzantine village at Scorpo (Supersano, Italy)(The Eurographics Association, 2013) Bandiera, Adriana; Arthur, Paul; Imperiale, Marco Leo; Maffezzoli, Alfonso; Frigione, Mariaenrica; Montagna, Francesco; Signore, Grazia Maria; -Artefacts found in an archaeological excavation are sometimes made of perishable or fragile material like wood, iron, or leather. These present obvious conservation problems. This is the case of various artefacts from the Byzantine village of Scorpo (Supersano, southern Italy) that has been the object of excavations by archaeologists from the University of Salento (Italy) since 1999. In 2007 a number of wooden objects were discovered in a well, while in 2012 a hoard of ferrous objects was found near a drystone wall that perhaps enclosed the settlement. Given the highly fragile and perishable nature of the objects, the questions arise as to how to study these artefacts, preserve them for the future and display them to the public. In this paper we will illustrate the methodology developed at the University of Salento to give an answer to all these questions and we will describe the entire process ranging from the discovery of the artefacts, to their 3D digital acquisition and modeling, the eventual digital restoration, the realization of one or more physical copies using a rapid prototyping apparatus (RP), to their display in a museum. Digital models of artefacts and ancient contexts are increasingly used in museums in order to improve communication, also for the disabled. Furthermore, the resin replica of an object, created from its digital 3D model, can also be useful for its preservation and fruition, especially if it is fragile or in poor condition.