2010
Software
Metadata Only Access
SpiderGL
Di Benedetto M
SpiderGL e' una libreria JavaScript per la grafica 3D che utilizza WebGL per la visualizzazione in tempo reale. La libreria offre agli sviluppatori di applicazioni web 3D strutture dati e algoritmi per la visualizzazione in tempo reale, senza imporre l'uso di uno specifico paradigma di programmazione (ad es. scene graph), e consente l'accesso a basso livello a WebGL.
Di Benedetto M
SpiderGL e' una libreria JavaScript per la grafica 3D che utilizza WebGL per la visualizzazione in tempo reale. La libreria offre agli sviluppatori di applicazioni web 3D strutture dati e algoritmi per la visualizzazione in tempo reale, senza imporre l'uso di uno specifico paradigma di programmazione (ad es. scene graph), e consente l'accesso a basso livello a WebGL.
See at:
CNR IRIS 
| spidergl.org
2011
Other
Open Access
Multiresolution Techniques for Real-Time Visualization of Urban Environments and Terrains
Di Benedetto M
In recent times we are witnessing a steep increase in the availability of data coming from real-life environments. Nowadays, virtually everyone connected to the Internet may have instant access to a tremendous amount of data coming from satellite elevation maps, airborne time-of-flight scanners and digital cameras, street-level photographs and even cadastral maps. As for other, more traditional types of media such as pictures and videos, users of digital exploration softwares expect commodity hardware to exhibit good performance for interactive purposes, regardless of the dataset size. In this thesis we propose novel solutions to the problem of rendering large terrain and urban models on commodity platforms, both for local and remote exploration. Our solutions build on the concept of multiresolution representation, where alternative representations of the same data with different accuracy are used to selectively distribute the computational power, and consequently the visual accuracy, where it is more needed on the base of the user's point of view. In particular, we will introduce an efficient multiresolution data compression technique for planar and spherical surfaces applied to terrain datasets which is able to handle huge amount of information at a planetary scale. We will also describe a novel data structure for compact storage and rendering of urban entities such as buildings to allow real-time exploration of cityscapes from a remote online repository. Moreover, we will show how recent technologies can be exploited to transparently integrate virtual exploration and general computer graphics techniques with web applications.
Di Benedetto M
In recent times we are witnessing a steep increase in the availability of data coming from real-life environments. Nowadays, virtually everyone connected to the Internet may have instant access to a tremendous amount of data coming from satellite elevation maps, airborne time-of-flight scanners and digital cameras, street-level photographs and even cadastral maps. As for other, more traditional types of media such as pictures and videos, users of digital exploration softwares expect commodity hardware to exhibit good performance for interactive purposes, regardless of the dataset size. In this thesis we propose novel solutions to the problem of rendering large terrain and urban models on commodity platforms, both for local and remote exploration. Our solutions build on the concept of multiresolution representation, where alternative representations of the same data with different accuracy are used to selectively distribute the computational power, and consequently the visual accuracy, where it is more needed on the base of the user's point of view. In particular, we will introduce an efficient multiresolution data compression technique for planar and spherical surfaces applied to terrain datasets which is able to handle huge amount of information at a planetary scale. We will also describe a novel data structure for compact storage and rendering of urban entities such as buildings to allow real-time exploration of cityscapes from a remote online repository. Moreover, we will show how recent technologies can be exploited to transparently integrate virtual exploration and general computer graphics techniques with web applications.
See at:
etd.adm.unipi.it 
| CNR IRIS | ISTI Repository | CNR IRIS
2011
Conference article
Restricted
Reconstructing and Exploring Massive Detailed Cityscapes
Gobbetti E, Marton F, Di Benedetto M, Ganovelli F, Buehler M, Schubiger S, Specht M, Engels C, Van Gool L
We present a state-of-the-art system for obtaining and exploring large scale thr ee-dimensional models of urban landscapes. A multimodal approach to reconstructi on fuses cadastral information, laser range data, and oblique imagery into build ing models, which are then refined by applying procedural rules for replacing te xtures with 3D elements, such as windows and doors, therefore enhancing the mode l quality and adding semantics to the model. For city scale exploration, these d etailed models are uploaded to a web-based service, which automatically constructs an approximate scalable multiresolution representation. This representation c an be interactively transmitted and visualized over the net to clients ranging from graphics PCs to web-enabled portable devices. The approach's characteristics and performance are illustrated using real-world city-scale data.DOI: 10.2312/vast/vast11/001-008
Project(s): V-CITY
Metrics:
Gobbetti E, Marton F, Di Benedetto M, Ganovelli F, Buehler M, Schubiger S, Specht M, Engels C, Van Gool L
We present a state-of-the-art system for obtaining and exploring large scale thr ee-dimensional models of urban landscapes. A multimodal approach to reconstructi on fuses cadastral information, laser range data, and oblique imagery into build ing models, which are then refined by applying procedural rules for replacing te xtures with 3D elements, such as windows and doors, therefore enhancing the mode l quality and adding semantics to the model. For city scale exploration, these d etailed models are uploaded to a web-based service, which automatically constructs an approximate scalable multiresolution representation. This representation c an be interactively transmitted and visualized over the net to clients ranging from graphics PCs to web-enabled portable devices. The approach's characteristics and performance are illustrated using real-world city-scale data.DOI: 10.2312/vast/vast11/001-008
Project(s): V-CITY
Metrics:
2006
Journal article
Open Access
C-BDAM - Compressed Batched Dynamic Adaptive Meshes for Terrain Rendering
Gobbetti E, Marton F, Cignoni P, Di Benedetto M, Ganovelli F
We describe a compressed multiresolution representation for supporting interactive rendering of very large planar and spherical terrain surfaces. The technique, called Compressed Batched Dynamic Adaptive Meshes (C-BDAM), is an extension of the BDAM and P-BDAM chunked level-of-detail hierarchy. In the C-BDAM approach, all patches share the same regular triangulation connectivity and incrementally encode their vertex attributes using a quantized representation of the difference with respect to values predicted from the coarser level. The structure provides a number of benefits: simplicity of data structures, overall geometric continuity for planar and spherical domains, support for variable resolution input data, management of multiple vertex attributes, efficient compression and fast construction times, ability to support maximum-error metrics, real-time decompression and shaded rendering with configurable variable level-of-detail extraction, and runtime detail synthesis. The efficiency of the approach and the achieved compression rates are demonstrated on a number of test cases, including the interactive visualization of a 29 gigasample reconstruction of the whole planet Earth created from high resolution SRTM data.Source: COMPUTER GRAPHICS FORUM (PRINT), vol. 25 (issue 3), pp. 333-342
DOI: 10.1111/j.1467-8659.2006.00952.x
Metrics:
Gobbetti E, Marton F, Cignoni P, Di Benedetto M, Ganovelli F
We describe a compressed multiresolution representation for supporting interactive rendering of very large planar and spherical terrain surfaces. The technique, called Compressed Batched Dynamic Adaptive Meshes (C-BDAM), is an extension of the BDAM and P-BDAM chunked level-of-detail hierarchy. In the C-BDAM approach, all patches share the same regular triangulation connectivity and incrementally encode their vertex attributes using a quantized representation of the difference with respect to values predicted from the coarser level. The structure provides a number of benefits: simplicity of data structures, overall geometric continuity for planar and spherical domains, support for variable resolution input data, management of multiple vertex attributes, efficient compression and fast construction times, ability to support maximum-error metrics, real-time decompression and shaded rendering with configurable variable level-of-detail extraction, and runtime detail synthesis. The efficiency of the approach and the achieved compression rates are demonstrated on a number of test cases, including the interactive visualization of a 29 gigasample reconstruction of the whole planet Earth created from high resolution SRTM data.Source: COMPUTER GRAPHICS FORUM (PRINT), vol. 25 (issue 3), pp. 333-342
DOI: 10.1111/j.1467-8659.2006.00952.x
Metrics:
See at:
Computer Graphics Forum | Computer Graphics Forum | CNR IRIS | CNR IRIS
2009
Conference article
Restricted
Interactive remote exploration of massive cityscapes
Di Benedetto M, Cignoni P, Ganovelli F, Gobbetti E, Marton F, Scopino R
We focus on developing a simple and efficient unified level-of-detail structure for networked urban model viewers. At the core of our approach is a revisitation of the BlockMap [CBGâ^-- 07] data structure, originally introduced for encoding coarse representations of blocks of buildings to be used as direction-independent impostors when ren- dering far-away city blocks. The contribution of this paper is manifold: we extend the BlockMap representation to support sloped surfaces and input-sensitive sampling of color; we introduce a novel sampling strategy for building accurate BlockMaps; we show that BlockMaps can be used as a versatile and robust way to parameterize the visi- ble surface of a highly complex model; we improve the expressiveness of urban models rendering by integrating an ambient occlusion term in the representation and describe an efficient method for computing it; we illustrate the design and implementation of a urban models streaming and visualization system and demonstrate its efficiency when browsing large city models in a limited bandwidth setting
Di Benedetto M, Cignoni P, Ganovelli F, Gobbetti E, Marton F, Scopino R
We focus on developing a simple and efficient unified level-of-detail structure for networked urban model viewers. At the core of our approach is a revisitation of the BlockMap [CBGâ^-- 07] data structure, originally introduced for encoding coarse representations of blocks of buildings to be used as direction-independent impostors when ren- dering far-away city blocks. The contribution of this paper is manifold: we extend the BlockMap representation to support sloped surfaces and input-sensitive sampling of color; we introduce a novel sampling strategy for building accurate BlockMaps; we show that BlockMaps can be used as a versatile and robust way to parameterize the visi- ble surface of a highly complex model; we improve the expressiveness of urban models rendering by integrating an ambient occlusion term in the representation and describe an efficient method for computing it; we illustrate the design and implementation of a urban models streaming and visualization system and demonstrate its efficiency when browsing large city models in a limited bandwidth setting
2010
Conference article
Restricted
Visualization methods for molecular studies on the Web platform
Callieri M, Andrei R M, Di Benedetto M, Zoppè M, Scopigno R
This work presents a technical solution for the creation of visualization schemes for biological data on the web platform. The proposed technology tries to overcome the standard approach of molecular/biochemical visualization tools, which generally provide a fixed set of visualization methods. This goal is reached by exploiting the capabilities of the WebGL API and the high level objects of the SpiderGL library, these features will give the users the possibility to implement an arbitrary visualization scheme, while keeping simple the implementation process. To better explain the philosophy and capabilities of this technology, we will describe the implementation of the web version of a specific visualization method, demonstrating how it can deal with both the requirements of scientific rigor in manipulating the data and the necessity to produce flexible and appealing rendering styles.DOI: 10.1145/1836049.1836067
Metrics:
Callieri M, Andrei R M, Di Benedetto M, Zoppè M, Scopigno R
This work presents a technical solution for the creation of visualization schemes for biological data on the web platform. The proposed technology tries to overcome the standard approach of molecular/biochemical visualization tools, which generally provide a fixed set of visualization methods. This goal is reached by exploiting the capabilities of the WebGL API and the high level objects of the SpiderGL library, these features will give the users the possibility to implement an arbitrary visualization scheme, while keeping simple the implementation process. To better explain the philosophy and capabilities of this technology, we will describe the implementation of the web version of a specific visualization method, demonstrating how it can deal with both the requirements of scientific rigor in manipulating the data and the necessity to produce flexible and appealing rendering styles.DOI: 10.1145/1836049.1836067
Metrics:
See at:
dl.acm.org | doi.org | CNR IRIS | CNR IRIS
2010
Conference article
Restricted
SpiderGL: a JavaScript 3D graphics library for next-generation WWW
Di Benedetto M, Ponchio F, Ganovelli F, Scopigno R
Thanks to the WebGL graphics API specification for the JavaScript programming language, the possibility of using the GPU capabilities in a web browser without the need for an ad-hoc plug-in is now coming true. This paper introduces SpiderGL, a JavaScript library for developing 3D graphics web applications. SpiderGL provides data structures and algorithms to ease the use of WebGL, to define and manipulate shapes, to import 3D models in various formats, to handle asynchronous data loading. We show the potential of this novel library with a number of demo applications. Furthermore, we introduce MeShade, a SpiderGL-based web application for shader material editing from within the web browser, which produces all the code needed for embedding interactive 3D model visualization capabilities inside web pages and online repositories.DOI: 10.1145/1836049.1836075
Metrics:
Di Benedetto M, Ponchio F, Ganovelli F, Scopigno R
Thanks to the WebGL graphics API specification for the JavaScript programming language, the possibility of using the GPU capabilities in a web browser without the need for an ad-hoc plug-in is now coming true. This paper introduces SpiderGL, a JavaScript library for developing 3D graphics web applications. SpiderGL provides data structures and algorithms to ease the use of WebGL, to define and manipulate shapes, to import 3D models in various formats, to handle asynchronous data loading. We show the potential of this novel library with a number of demo applications. Furthermore, we introduce MeShade, a SpiderGL-based web application for shader material editing from within the web browser, which produces all the code needed for embedding interactive 3D model visualization capabilities inside web pages and online repositories.DOI: 10.1145/1836049.1836075
Metrics:
See at:
doi.org | CNR IRIS | CNR IRIS | puma.isti.cnr.it
2008
Software
Metadata Only Access
BlockMap Engine
Di Benedetto M, Cignoni P, Fabio Ganovelli F, Scopigno R
BlockMaps engine is a multiplatform opensource application for real time rendering of massive urban dataset. It is entirely written in c++ with Qt and OpenGl library. The BlockMaps engine has been deployed in the framework of the CRIMSON project (CRIMSON: The Crisis Simulation System EU Fifth Framework Program Reference: SEC4-PR-011500)
Di Benedetto M, Cignoni P, Fabio Ganovelli F, Scopigno R
BlockMaps engine is a multiplatform opensource application for real time rendering of massive urban dataset. It is entirely written in c++ with Qt and OpenGl library. The BlockMaps engine has been deployed in the framework of the CRIMSON project (CRIMSON: The Crisis Simulation System EU Fifth Framework Program Reference: SEC4-PR-011500)
See at:
CNR IRIS
2007
Other
Open Access
Ray-casted BlockMaps for large urban models streaming and visualization
Cignoni P, Di Benedetto M, Ganovelli F, Gobbetti E, Marton F, Scopigno R
We introduce a network- and GPU-friendly technique that efficiently exploits the highly structured nature of urban environments to ensure rendering quality and interactive performance of city exploration tasks. Central to our approach is a novel discrete representation, called BlockMap, for the efficient encoding, transmission and rendering of a small set of textured buildings far from the viewer. A BlockMap compactly represents a set of textured vertical prisms with a bounded on-screen footprint. BlockMaps are stored into small fixed size texture chunks and efficiently rendered through GPU raycasting. Blockmaps can be seamlessly integrated into hierarchical data structures for interactive rendering of large textured urban models. We illustrate an efficient output-sensitive framework in which a visibility-aware traversal of the hierarchy renders components close to the viewer with textured polygons and employs BlockMaps for far away geometry. Our approach provides a bounded size far distance representation of cities, naturally scales with the improving shader technology, and outperforms current state of the art approaches. Its efficiency and generality is demonstrated with the interactive exploration of a large textured model of the city of Paris on a commodity graphics platform.Source: COMPUTER GRAPHICS FORUM (PRINT), pp. 405-413
DOI: 10.1111/j.1467-8659.2007.01063.x
Metrics:
Cignoni P, Di Benedetto M, Ganovelli F, Gobbetti E, Marton F, Scopigno R
We introduce a network- and GPU-friendly technique that efficiently exploits the highly structured nature of urban environments to ensure rendering quality and interactive performance of city exploration tasks. Central to our approach is a novel discrete representation, called BlockMap, for the efficient encoding, transmission and rendering of a small set of textured buildings far from the viewer. A BlockMap compactly represents a set of textured vertical prisms with a bounded on-screen footprint. BlockMaps are stored into small fixed size texture chunks and efficiently rendered through GPU raycasting. Blockmaps can be seamlessly integrated into hierarchical data structures for interactive rendering of large textured urban models. We illustrate an efficient output-sensitive framework in which a visibility-aware traversal of the hierarchy renders components close to the viewer with textured polygons and employs BlockMaps for far away geometry. Our approach provides a bounded size far distance representation of cities, naturally scales with the improving shader technology, and outperforms current state of the art approaches. Its efficiency and generality is demonstrated with the interactive exploration of a large textured model of the city of Paris on a commodity graphics platform.Source: COMPUTER GRAPHICS FORUM (PRINT), pp. 405-413
DOI: 10.1111/j.1467-8659.2007.01063.x
Metrics:
See at:
CNR IRIS | ISTI Repository | puma.isti.cnr.it | Computer Graphics Forum | CNR IRIS
2009
Conference article
Restricted
Interactive Remote Exploration of Massive Cityscapes
Di Benedetto M, Cignoni P, Ganovelli F, Gobbetti E, Marton F, Scopigno R
We focus on developing a simple and efficient unified level-of-detail structure for networked urban model viewers. At the core of our approach is a revisitation of the BlockMap [CDG*07] data structure, originally introduced for encoding coarse representations of blocks of buildings to be used as direction-independent impostors when rendering far-away city blocks. The contribution of this paper is manifold: we extend the BlockMap representation to support sloped surfaces and input-sensitive sampling of color; we introduce a novel sampling strategy for building accurate BlockMaps; we show that BlockMaps can be used as a versatile and robust way to parameterize the visible surface of a highly complex model; we improve the expressiveness of urban models rendering by integrating an ambient occlusion term in the representation and describe an efficient method for computing it; we illustrate the design and implementation of a urban models streaming and visualization system and demonstrate its efficiency when browsing large city models in a limited bandwidth setting.DOI: 10.2312/vast/vast09/009-016
Metrics:
Di Benedetto M, Cignoni P, Ganovelli F, Gobbetti E, Marton F, Scopigno R
We focus on developing a simple and efficient unified level-of-detail structure for networked urban model viewers. At the core of our approach is a revisitation of the BlockMap [CDG*07] data structure, originally introduced for encoding coarse representations of blocks of buildings to be used as direction-independent impostors when rendering far-away city blocks. The contribution of this paper is manifold: we extend the BlockMap representation to support sloped surfaces and input-sensitive sampling of color; we introduce a novel sampling strategy for building accurate BlockMaps; we show that BlockMaps can be used as a versatile and robust way to parameterize the visible surface of a highly complex model; we improve the expressiveness of urban models rendering by integrating an ambient occlusion term in the representation and describe an efficient method for computing it; we illustrate the design and implementation of a urban models streaming and visualization system and demonstrate its efficiency when browsing large city models in a limited bandwidth setting.DOI: 10.2312/vast/vast09/009-016
Metrics:
See at:
diglib.eg.org | CNR IRIS | CNR IRIS
2011
Other
Restricted
A low-cost time-critical obstacle avoidance system for the visually impaired
Bernabei D, Ganovelli F, Di Benedetto M, Dellepiane M, Scopigno R
We present a low cost system for unassisted mobility of blind people built with off-the-shelf technology. Our system takes as input the depth maps produced by the Kinectic device coupled with the data from its accelerometer to provide a registered point based 3D representation of the scene in front of the user. We developed a time-critical framework to analyze the scene and classify the ground and still or moving obstacles and provide the user with a constant and reliable feedback.
Bernabei D, Ganovelli F, Di Benedetto M, Dellepiane M, Scopigno R
We present a low cost system for unassisted mobility of blind people built with off-the-shelf technology. Our system takes as input the depth maps produced by the Kinectic device coupled with the data from its accelerometer to provide a registered point based 3D representation of the scene in front of the user. We developed a time-critical framework to analyze the scene and classify the ground and still or moving obstacles and provide the user with a constant and reliable feedback.
2011
Other
Open Access
A parallel architecture for interactive rendering of scattering and refraction effects
Bernabei D, Hakke Patil A, Banterle F, Di Benedetto M, Ganovelli F, Pattanaik S, Scopigno R
We present a new algorithm for the interactive rendering of complex lighting effects inside heterogeneous materials. Our approach combines accurate tracing of the light rays in heterogeneous refractive medium to compute high frequency phenomena, with a lattice-Boltzmann method to account for low-frequency multiple scattering effects. The presented technique is designed for parallel execution of these two algorithms on modern graphics hardware. In our solution, light marches from the sources into the medium, taking into account refraction, scattering and absorption. During the marching of the light rays inside the volumetric representation of the scene, irradiance is accumulated and it is diffused with the lattice-Boltzmann method to produce multiple scattering effects.
Bernabei D, Hakke Patil A, Banterle F, Di Benedetto M, Ganovelli F, Pattanaik S, Scopigno R
We present a new algorithm for the interactive rendering of complex lighting effects inside heterogeneous materials. Our approach combines accurate tracing of the light rays in heterogeneous refractive medium to compute high frequency phenomena, with a lattice-Boltzmann method to account for low-frequency multiple scattering effects. The presented technique is designed for parallel execution of these two algorithms on modern graphics hardware. In our solution, light marches from the sources into the medium, taking into account refraction, scattering and absorption. During the marching of the light rays inside the volumetric representation of the scene, irradiance is accumulated and it is diffused with the lattice-Boltzmann method to produce multiple scattering effects.
See at:
CNR IRIS | ISTI Repository | CNR IRIS
2012
Contribution to book
Restricted
Features And Design Choices in SpiderGL.
Di Benedetto M, Ganovelli F, Banterle F
Technologies related to Computer Graphics (CG) are constantly growing. This is mostly due to the widespread availability of 3D acceleration hard- ware with an unprecedented ratio of performance to cost. In the past, access to such accelerators was conned to workstations; nowadays, even hand-held devices such as smartphones are equipped with powerful graph- ics hardware. On a parallel time line, with the introduction of OpenGL, CG software moved to proprietary solutions from royalty free specications. In addition, widespread access to broadband Internet connections led to a tremendous increase in content availability, as well as a great enrichment of web technologies, such as HTML5. In this mature scenario, the WebGL specication was introduced to allow CG and Web programmers to leverage the power of GPUs directly within web pages. WebGL is a powerful technology based on the OpenGLjES 2.0 specication, and it thus adheres the philosophy of a barebones low-level API. As it happens in similar contexts, a series of higher-level libraries have been developed to ease usage and implement more complex constructs. SpiderGL [Di Benedetto et al. 10] is a JavaScript CG library that uses WebGL for real-time rendering. The library exposes a series of utilities, data structures, and algorithms to serve typical graphics tasks. When de- veloping SpiderGL, we wanted to create a library able to simplify the most common usage pattern of WebGL, and that could guarantee a seamless in- tegration into complex software packages. Its role of middleware imposed on us a need to enforce consistency whenever users wanted to access the underlying WebGL layer, and to provide a solid foundation for the devel- opment of higher-level components.Project(s): V-CITY
Di Benedetto M, Ganovelli F, Banterle F
Technologies related to Computer Graphics (CG) are constantly growing. This is mostly due to the widespread availability of 3D acceleration hard- ware with an unprecedented ratio of performance to cost. In the past, access to such accelerators was conned to workstations; nowadays, even hand-held devices such as smartphones are equipped with powerful graph- ics hardware. On a parallel time line, with the introduction of OpenGL, CG software moved to proprietary solutions from royalty free specications. In addition, widespread access to broadband Internet connections led to a tremendous increase in content availability, as well as a great enrichment of web technologies, such as HTML5. In this mature scenario, the WebGL specication was introduced to allow CG and Web programmers to leverage the power of GPUs directly within web pages. WebGL is a powerful technology based on the OpenGLjES 2.0 specication, and it thus adheres the philosophy of a barebones low-level API. As it happens in similar contexts, a series of higher-level libraries have been developed to ease usage and implement more complex constructs. SpiderGL [Di Benedetto et al. 10] is a JavaScript CG library that uses WebGL for real-time rendering. The library exposes a series of utilities, data structures, and algorithms to serve typical graphics tasks. When de- veloping SpiderGL, we wanted to create a library able to simplify the most common usage pattern of WebGL, and that could guarantee a seamless in- tegration into complex software packages. Its role of middleware imposed on us a need to enforce consistency whenever users wanted to access the underlying WebGL layer, and to provide a solid foundation for the devel- opment of higher-level components.Project(s): V-CITY
See at:
CNR IRIS | CNR IRIS | openglinsights.com
2012
Journal article
Restricted
A parallel architecture for interactively rendering scattering and refraction effects
Bernabei D, Hakkepatil A, Banterle F, Di Benedetto M, Ganovelli F, Pattanaik S, Scopigno R
A new method for interactive rendering of complex lighting effects combines two algorithms. The first performs accurate ray tracing in heterogeneous refractive media to compute high-frequency phenomena. The second applies lattice-Boltzmann lighting to account for low-frequency multiple-scattering effects. The two algorithms execute in parallel on modern graphics hardware. This article includes a video animation of the authors' real-time algorithm rendering a variety of scenesSource: IEEE COMPUTER GRAPHICS AND APPLICATIONS (ONLINE), vol. 32 (issue 2), pp. 34-43
DOI: 10.1109/mcg.2011.106
Project(s): 3D-COFORM
Metrics:
Bernabei D, Hakkepatil A, Banterle F, Di Benedetto M, Ganovelli F, Pattanaik S, Scopigno R
A new method for interactive rendering of complex lighting effects combines two algorithms. The first performs accurate ray tracing in heterogeneous refractive media to compute high-frequency phenomena. The second applies lattice-Boltzmann lighting to account for low-frequency multiple-scattering effects. The two algorithms execute in parallel on modern graphics hardware. This article includes a video animation of the authors' real-time algorithm rendering a variety of scenesSource: IEEE COMPUTER GRAPHICS AND APPLICATIONS (ONLINE), vol. 32 (issue 2), pp. 34-43
DOI: 10.1109/mcg.2011.106
Project(s): 3D-COFORM
Metrics:
See at:
IEEE Computer Graphics and Applications | CNR IRIS | ieeexplore.ieee.org | CNR IRIS
2012
Journal article
Open Access
From the digitization of cultural artifacts to the web publishing of digital 3D collections: an automatic pipeline for knowledge sharing
Larue F, Di Benedetto M, Dellepiane M, Scopigno R
In this paper, we introduce a novel approach intended to simplify the production of multimedia content from real objects for the purpose of knowledge sharing, which is particularly appropriate to the cultural heritage field. It consists in a pipeline that covers all steps from the digitization of the objects up to the Web publishing of the resulting digital copies. During a first stage, the digitization is performed by a high speed 3D scanner that recovers the object's geometry. A second stage then extracts from the recovered data a color texture as well as a texture of details, in order to enrich the acquired geometry in a more realistic way. Finally, a third stage converts these data so that they are compatible with the recent WebGL paradigm, then providing 3D multimedia content directly exploitable by end-users by means of standard Internet browsers. The pipeline design is centered on automation and speed, so that it can be used by non expert users to produce multimedia content from potentially large object's collections, like it may be the case in cultural heritage. The choice of a high speed scanner is particularly adapted for such a design, since this kind of devices has the advantage of being fast and intuitive. Processing stages that follow the digitization are both completely automatic and ``seamless'', in the sense that it is not incumbent upon the user to perform tasks manually, nor to use external softwares that generally need additional operations to solve compatibility issues.Source: JOURNAL OF MULTIMEDIA, vol. 7 (issue 2), pp. 133-144
DOI: 10.4304/jmm.7.2.132-144
Project(s): 3D-COFORM
Metrics:
Larue F, Di Benedetto M, Dellepiane M, Scopigno R
In this paper, we introduce a novel approach intended to simplify the production of multimedia content from real objects for the purpose of knowledge sharing, which is particularly appropriate to the cultural heritage field. It consists in a pipeline that covers all steps from the digitization of the objects up to the Web publishing of the resulting digital copies. During a first stage, the digitization is performed by a high speed 3D scanner that recovers the object's geometry. A second stage then extracts from the recovered data a color texture as well as a texture of details, in order to enrich the acquired geometry in a more realistic way. Finally, a third stage converts these data so that they are compatible with the recent WebGL paradigm, then providing 3D multimedia content directly exploitable by end-users by means of standard Internet browsers. The pipeline design is centered on automation and speed, so that it can be used by non expert users to produce multimedia content from potentially large object's collections, like it may be the case in cultural heritage. The choice of a high speed scanner is particularly adapted for such a design, since this kind of devices has the advantage of being fast and intuitive. Processing stages that follow the digitization are both completely automatic and ``seamless'', in the sense that it is not incumbent upon the user to perform tasks manually, nor to use external softwares that generally need additional operations to solve compatibility issues.Source: JOURNAL OF MULTIMEDIA, vol. 7 (issue 2), pp. 133-144
DOI: 10.4304/jmm.7.2.132-144
Project(s): 3D-COFORM
Metrics:
See at:
Journal of Multimedia | Journal of Multimedia | Hyper Article en Ligne | CNR IRIS | CNR IRIS | ojs.academypublisher.com
2014
Journal article
Restricted
eXploreMaps: efficient construction and ubiquitous exploration of panoramic view graphics of complex 3D environments
Di Benedetto M, Ganovelli F, Balsa Rodriguez M, Jaspe Villanueva A, Gobbetti E, Scopigno R
We introduce a novel efficient technique for automatically transforming a generic renderable 3D scene into a simple graph representation named ExploreMaps, where nodes are nicely placed point of views, called probes, and arcs are smooth paths between neighboring probes. Each probe is associated with a panoramic image enriched with preferred viewing orientations, and each path with a panoramic video. Our GPU-accelerated unattended construction pipeline distributes probes so as to guarantee coverage of the scene while accounting for perceptual criteria before finding smooth, good looking paths between neighboring probes. Images and videos are precomputed at construction time with off-line photorealistic rendering engines, providing a convincing 3D visualization beyond the limits of current real-time graphics techniques. At run-time, the graph is exploited both for creating automatic scene indexes and movie previews of complex scenes and for supporting interactive exploration through a low-DOF assisted navigation interface and the visual indexing of the scene provided by the selected viewpoints. Due to negligible CPU overhead and very limited use of GPU functionality, real-time performance is achieved on emerging web-based environments based on WebGL even on low-powered mobile devices.Source: COMPUTER GRAPHICS FORUM (ONLINE), vol. 33 (issue 22), pp. 459-468
DOI: 10.1111/cgf.12334
Metrics:
Di Benedetto M, Ganovelli F, Balsa Rodriguez M, Jaspe Villanueva A, Gobbetti E, Scopigno R
We introduce a novel efficient technique for automatically transforming a generic renderable 3D scene into a simple graph representation named ExploreMaps, where nodes are nicely placed point of views, called probes, and arcs are smooth paths between neighboring probes. Each probe is associated with a panoramic image enriched with preferred viewing orientations, and each path with a panoramic video. Our GPU-accelerated unattended construction pipeline distributes probes so as to guarantee coverage of the scene while accounting for perceptual criteria before finding smooth, good looking paths between neighboring probes. Images and videos are precomputed at construction time with off-line photorealistic rendering engines, providing a convincing 3D visualization beyond the limits of current real-time graphics techniques. At run-time, the graph is exploited both for creating automatic scene indexes and movie previews of complex scenes and for supporting interactive exploration through a low-DOF assisted navigation interface and the visual indexing of the scene provided by the selected viewpoints. Due to negligible CPU overhead and very limited use of GPU functionality, real-time performance is achieved on emerging web-based environments based on WebGL even on low-powered mobile devices.Source: COMPUTER GRAPHICS FORUM (ONLINE), vol. 33 (issue 22), pp. 459-468
DOI: 10.1111/cgf.12334
Metrics:
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Computer Graphics Forum | CNR IRIS | CNR IRIS | onlinelibrary.wiley.com
2014
Book
Metadata Only Access
Introduction to Computer Graphics: a practical learning approach
Ganovelli F, Corsini M, Pattanaik S, Di Benedetto M
This book guides students in developing their own interactive graphics application. The authors show step by step how to implement computer graphics concepts and theory using the EnvyMyCar (NVMC) framework as a consistent example throughout the text. They use the WebGL graphics API to develop NVMC, a simple, interactive car racing game. Each chapter focuses on a particular computer graphics aspect, such as 3D modeling and lighting. The authors help students understand how to handle 3D geometric transformations, texturing, complex lighting effects, and more. This practical approach leads students to draw the elements and effects needed to ultimately create a visually pleasing car racing game.
Ganovelli F, Corsini M, Pattanaik S, Di Benedetto M
This book guides students in developing their own interactive graphics application. The authors show step by step how to implement computer graphics concepts and theory using the EnvyMyCar (NVMC) framework as a consistent example throughout the text. They use the WebGL graphics API to develop NVMC, a simple, interactive car racing game. Each chapter focuses on a particular computer graphics aspect, such as 3D modeling and lighting. The authors help students understand how to handle 3D geometric transformations, texturing, complex lighting effects, and more. This practical approach leads students to draw the elements and effects needed to ultimately create a visually pleasing car racing game.
See at:
CNR IRIS | www.crcpress.com
2011
Conference article
Open Access
Spidergl: A graphics library for 3D web applications
Di Benedetto M, Corsini M, Scopigno R
The recent introduction of the WebGL API for leveraging the power of 3D graphics accelerators within Web browsers opens the possibility to develop advanced graphics applications without the need for an ad-hoc plug-in. There are several contexts in which this new technology can be exploited to enhance user experience and data fruition, like e-commerce applications, games and, in particular, Cultural Heritage. In fact, it is now possible to use the Web platform to present a virtual reconstruction hypothesis of ancient pasts, to show detailed 3D models of artefacts of interests to a wide public, and to create virtual museums. We introduce SpiderGL, a JavaScript library for developing 3D graphics Web applications. SpiderGL provides data structures and algorithms to ease the use of WebGL, to define and manipulate shapes, to import 3D models in various formats, and to handle asynchronous data loading. We show the potential of this novel library with a number of demo applications and give details about its future uses in the context of Cultural Heritage applications.Source: INTERNATIONAL ARCHIVES OF THE PHOTOGRAMMETRY, REMOTE SENSING AND SPATIAL INFORMATION SCIENCES, vol. 38, pp. 467-474. Trento, Italy, 4-8 March 2011
DOI: 10.5194/isprsarchives-xxxviii-5-w16-467-2011
Metrics:
Di Benedetto M, Corsini M, Scopigno R
The recent introduction of the WebGL API for leveraging the power of 3D graphics accelerators within Web browsers opens the possibility to develop advanced graphics applications without the need for an ad-hoc plug-in. There are several contexts in which this new technology can be exploited to enhance user experience and data fruition, like e-commerce applications, games and, in particular, Cultural Heritage. In fact, it is now possible to use the Web platform to present a virtual reconstruction hypothesis of ancient pasts, to show detailed 3D models of artefacts of interests to a wide public, and to create virtual museums. We introduce SpiderGL, a JavaScript library for developing 3D graphics Web applications. SpiderGL provides data structures and algorithms to ease the use of WebGL, to define and manipulate shapes, to import 3D models in various formats, and to handle asynchronous data loading. We show the potential of this novel library with a number of demo applications and give details about its future uses in the context of Cultural Heritage applications.Source: INTERNATIONAL ARCHIVES OF THE PHOTOGRAMMETRY, REMOTE SENSING AND SPATIAL INFORMATION SCIENCES, vol. 38, pp. 467-474. Trento, Italy, 4-8 March 2011
DOI: 10.5194/isprsarchives-xxxviii-5-w16-467-2011
Metrics:
See at:
ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences | ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences | ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences | CNR IRIS | CNR IRIS | www.int-arch-photogramm-remote-sens-spatial-inf-sci.net | www.scopus.com
2007
Journal article
Restricted
Ray-casted BlockMaps for large urban models visualization
Cignoni P, Di Benedetto M, Ganovelli F, Gobbetti E, Marton F, Scopigno R
We introduce a network- and GPU-friendly technique that efficiently exploits the highly structured nature of urban environments to ensure rendering quality and interactive performance of city exploration tasks. Central to our approach is a novel discrete representation, called BlockMap, for the efficient encoding, transmission and rendering of a small set of textured buildings far from the viewer. A BlockMap compactly represents a set of textured vertical prisms with a bounded on-screen footprint. BlockMaps are stored into small fixed size texture chunks and efficiently rendered through GPU raycasting. Blockmaps can be seamlessly integrated into hierarchical data structures for interactive rendering of large textured urban models. We illustrate an efficient output-sensitive framework in which a visibility-aware traversal of the hierarchy renders components close to the viewer with textured polygons and employs BlockMaps for far away geometry. Our approach provides a bounded size far distance representation of cities, naturally scales with the improving shader technology, and outperforms current state of the art approaches. Its efficiency and generality is demonstrated with the interactive exploration of a large textured model of the city of Paris on a commodity graphics platform.Source: COMPUTER GRAPHICS FORUM (PRINT), vol. 26 (issue 3), pp. 405-413
DOI: 10.1111/j.1467-8659.2007.01063.x
Metrics:
Cignoni P, Di Benedetto M, Ganovelli F, Gobbetti E, Marton F, Scopigno R
We introduce a network- and GPU-friendly technique that efficiently exploits the highly structured nature of urban environments to ensure rendering quality and interactive performance of city exploration tasks. Central to our approach is a novel discrete representation, called BlockMap, for the efficient encoding, transmission and rendering of a small set of textured buildings far from the viewer. A BlockMap compactly represents a set of textured vertical prisms with a bounded on-screen footprint. BlockMaps are stored into small fixed size texture chunks and efficiently rendered through GPU raycasting. Blockmaps can be seamlessly integrated into hierarchical data structures for interactive rendering of large textured urban models. We illustrate an efficient output-sensitive framework in which a visibility-aware traversal of the hierarchy renders components close to the viewer with textured polygons and employs BlockMaps for far away geometry. Our approach provides a bounded size far distance representation of cities, naturally scales with the improving shader technology, and outperforms current state of the art approaches. Its efficiency and generality is demonstrated with the interactive exploration of a large textured model of the city of Paris on a commodity graphics platform.Source: COMPUTER GRAPHICS FORUM (PRINT), vol. 26 (issue 3), pp. 405-413
DOI: 10.1111/j.1467-8659.2007.01063.x
Metrics:
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Computer Graphics Forum | CNR IRIS | CNR IRIS
2019
Conference article
Open Access
Learning Safety Equipment Detection using Virtual Worlds
Di Benedetto M, Meloni E, Amato G, Falchi F, Gennaro C
Nowadays, the possibilities offered by state-of-The-Art deep neural networks allow the creation of systems capable of recognizing and indexing visual content with very high accuracy. Performance of these systems relies on the availability of high quality training sets, containing a large number of examples (e.g. million), in addition to the the machine learning tools themselves. For several applications, very good training sets can be obtained, for example, crawling (noisily) annotated images from the internet, or by analyzing user interaction (e.g.: on social networks). However, there are several applications for which high quality training sets are not easy to be obtained/created. Consider, as an example, a security scenario where one wants to automatically detect rarely occurring threatening events. In this respect, recently, researchers investigated the possibility of using a visual virtual environment, capable of artificially generating controllable and photo-realistic contents, to create training sets for applications with little available training images. We explored this idea to generate synthetic photo-realistic training sets to train classifiers to recognize the proper use of individual safety equipment (e.g.: worker protection helmets, high-visibility vests, ear protection devices) during risky human activities. Then, we performed domain adaptation to real images by using a very small image data set of real-world photographs. We show that training with the generated synthetic training set and using the domain adaptation step is an effective solution to address applications for which no training sets exist.Source: PROCEEDINGS INTERNATIONAL WORKSHOP ON CONTENT-BASED MULTIMEDIA, vol. 2019-September. Dublin, Ireland, 4/9/2019, 6/9/2019
DOI: 10.1109/cbmi.2019.8877466
Project(s): AI4EU
Metrics:
Di Benedetto M, Meloni E, Amato G, Falchi F, Gennaro C
Nowadays, the possibilities offered by state-of-The-Art deep neural networks allow the creation of systems capable of recognizing and indexing visual content with very high accuracy. Performance of these systems relies on the availability of high quality training sets, containing a large number of examples (e.g. million), in addition to the the machine learning tools themselves. For several applications, very good training sets can be obtained, for example, crawling (noisily) annotated images from the internet, or by analyzing user interaction (e.g.: on social networks). However, there are several applications for which high quality training sets are not easy to be obtained/created. Consider, as an example, a security scenario where one wants to automatically detect rarely occurring threatening events. In this respect, recently, researchers investigated the possibility of using a visual virtual environment, capable of artificially generating controllable and photo-realistic contents, to create training sets for applications with little available training images. We explored this idea to generate synthetic photo-realistic training sets to train classifiers to recognize the proper use of individual safety equipment (e.g.: worker protection helmets, high-visibility vests, ear protection devices) during risky human activities. Then, we performed domain adaptation to real images by using a very small image data set of real-world photographs. We show that training with the generated synthetic training set and using the domain adaptation step is an effective solution to address applications for which no training sets exist.Source: PROCEEDINGS INTERNATIONAL WORKSHOP ON CONTENT-BASED MULTIMEDIA, vol. 2019-September. Dublin, Ireland, 4/9/2019, 6/9/2019
DOI: 10.1109/cbmi.2019.8877466
Project(s): AI4EU
Metrics:
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CNR IRIS | ieeexplore.ieee.org | ISTI Repository | doi.org | CNR IRIS | CNR IRIS