2013
Other
Restricted
Surface Appearance Estimation from Video Sequences
Palma G
The realistic virtual reproduction of real world objects using Computer Graphics techniques requires the accurate acquisition and reconstruction of both 3D geometry and surface appearance. Unfortunately, in several application contexts, such as Cultural Heritage (CH), the reflectance acquisition can be very challenging due to the type of object to acquire and the digitization conditions. Although several methods have been proposed for the acquisition of object reflectance, some intrinsic limitations still make its acquisition a complex task for CH artworks: the use of specialized instruments (dome, special setup for camera and light source, etc.); the need of highly controlled acquisition environments, such as a dark room; the difficulty to extend to objects of arbitrary shape and size; the high level of expertise required to assess the quality of the acquisition. The Ph.D. thesis proposes novel solutions for the acquisition and the estimation of the surface appearance in fixed and uncontrolled lighting conditions with several degree of approximations (from a perceived near diffuse color to a SVBRDF), taking advantage of the main features that differentiate a video sequences from an unordered photos collections: the temporal coherence; the data redundancy; the easy of the acquisition, which allows acquisition of many views of the object in a short time. Finally, Reflectance Transformation Imaging (RTI) is an example of widely used technology for the acquisition of the surface appearance in the CH field, even if limited to single view Reflectance Fields of nearly flat objects. In this context, the thesis addresses also two important issues in RTI usage: how to provide better and more flexible virtual inspection capabilities with a set of operators that improve the perception of details, features and overall shape of the artwork; how to increase the possibility to disseminate this data and to support remote visual inspection of both scholar and ordinary public.
Palma G
The realistic virtual reproduction of real world objects using Computer Graphics techniques requires the accurate acquisition and reconstruction of both 3D geometry and surface appearance. Unfortunately, in several application contexts, such as Cultural Heritage (CH), the reflectance acquisition can be very challenging due to the type of object to acquire and the digitization conditions. Although several methods have been proposed for the acquisition of object reflectance, some intrinsic limitations still make its acquisition a complex task for CH artworks: the use of specialized instruments (dome, special setup for camera and light source, etc.); the need of highly controlled acquisition environments, such as a dark room; the difficulty to extend to objects of arbitrary shape and size; the high level of expertise required to assess the quality of the acquisition. The Ph.D. thesis proposes novel solutions for the acquisition and the estimation of the surface appearance in fixed and uncontrolled lighting conditions with several degree of approximations (from a perceived near diffuse color to a SVBRDF), taking advantage of the main features that differentiate a video sequences from an unordered photos collections: the temporal coherence; the data redundancy; the easy of the acquisition, which allows acquisition of many views of the object in a short time. Finally, Reflectance Transformation Imaging (RTI) is an example of widely used technology for the acquisition of the surface appearance in the CH field, even if limited to single view Reflectance Fields of nearly flat objects. In this context, the thesis addresses also two important issues in RTI usage: how to provide better and more flexible virtual inspection capabilities with a set of operators that improve the perception of details, features and overall shape of the artwork; how to increase the possibility to disseminate this data and to support remote visual inspection of both scholar and ordinary public.
See at:
etd.adm.unipi.it 
| CNR IRIS | CNR IRIS
2012
Conference article
Restricted
Insourcing, outsourcing and crowdsourcing 3D collection formation: perspectives for cultural heritage sites
Kaminski J, Echavarria K R, Arnold D, Palma G, Scopigno R, Proesmans M, Stevenson J
This paper presents three different propositions for cultural heritage organisations on how to digitise objects in 3D. It is based on the practical evaluation of three different deployment experiments that use different methods and business models for mass 3D-acquisition. These models are: developing the skills of in-house staff within an organisation, the use of external professionals and using crowdsourcing as a mechanism for developing the 3D collection. Furthermore, the paper provides an analysis of these models, lessons learned and practical recommendations for cultural heritage organisations. The analysis includes considerations of issues such as strategy, size of the organisation, skills, equipment, object accessibility and complexity as well as the cost, time and quality of the 3D technology. The paper concludes that most organisations are able to develop 3D collections but variations in the result will be reflected by the strategic approach they place on innovative 3D technologiesProject(s): 3D-COFORM
Kaminski J, Echavarria K R, Arnold D, Palma G, Scopigno R, Proesmans M, Stevenson J
This paper presents three different propositions for cultural heritage organisations on how to digitise objects in 3D. It is based on the practical evaluation of three different deployment experiments that use different methods and business models for mass 3D-acquisition. These models are: developing the skills of in-house staff within an organisation, the use of external professionals and using crowdsourcing as a mechanism for developing the 3D collection. Furthermore, the paper provides an analysis of these models, lessons learned and practical recommendations for cultural heritage organisations. The analysis includes considerations of issues such as strategy, size of the organisation, skills, equipment, object accessibility and complexity as well as the cost, time and quality of the 3D technology. The paper concludes that most organisations are able to develop 3D collections but variations in the result will be reflected by the strategic approach they place on innovative 3D technologiesProject(s): 3D-COFORM
See at:
diglib.eg.org | CNR IRIS | CNR IRIS
2014
Conference article
Open Access
Storytelling of a coin collection by means of RTI images: the case of the Simoneschi Collection in Palazzo Blu
Palma G, Baldassarri M, Favilla M C, Scopigno R
Reflectance Transformation Imaging (RTI) is a technique that captures a subject's surface shape and color and enables the interactive re-lighting of the subject from any direction. Although at the beginning this technique was designed to aid Cultural Heritage specialists in the inspection and interpretation process, the recent advances of 3D web visualization platforms are increasing our capability to open this type of visual inspection to the ordinary public. Especially the methodologies for virtual manipulation of Cultural Heritage artifacts through RTI are gaining interest. In this context one of the most interesting kind of objects to acquire and virtually explore by means of RTI images are the ancient coins collections. Typically, a coin is a very small artwork, presented to the public from a distance and visible only from one side. Furthermore, coins have a lot of hidden knowledge that is difficult to transfer to the visitors in an easy, effective and understandable manner. What we present is the use of this new multimedia data, RTI images, in the process of digitalization and virtual presentation of the coin collection of the Palazzo Blu Museum (Pisa, Italy). The main goal of the project was to provide an improved access of ordinary people (visitors of the museum or web surfers) to the exposed numismatic materials. The result of this activity is an interactive kiosk that, integrated with the existing traditional museum exhibition, allows the visitors to interact and virtually explore every coin. The interactive presentation system, developed in HTML5 and designed to be deployed either by a museum kiosk or by a web site, is composed by a presentation section and the interactive viewer of the RTI images of each coin. The presentation part contains the description of the project and the organization of the coins into different subsets, using historical and thematic criteria, with the purpose to provide a presentation to a public of ordinary museum visitors. The RTI viewer offers a set of basic functionalities for the virtual manipulation of the coins using high-resolution images produced by RTI techniques. The RTI image of the coin, generated from a set of images acquired from the same point of view but with different lighting conditions, allows the visitor to change the direction of light in real time, making visible and appreciable details otherwise imperceptible. The virtual manipulation is completed by the free navigation on the coin, with basic operations like pan and zoom, and the possibility to flip the coin, to interact with the reverse, and to explore small areas of interest, identified by some hot spots on the surface and associated with text and pictures that provide additional information about the most interesting and important technical, historical and artistic features of the piece. The kiosk is currently installed inside the Museum Palazzo Blu in Pisa, in the exhibition room of the Ottavio Simoneschi's coin collection, and it will be soon loaded on the museum web site.Project(s): V-MUST.NET
Palma G, Baldassarri M, Favilla M C, Scopigno R
Reflectance Transformation Imaging (RTI) is a technique that captures a subject's surface shape and color and enables the interactive re-lighting of the subject from any direction. Although at the beginning this technique was designed to aid Cultural Heritage specialists in the inspection and interpretation process, the recent advances of 3D web visualization platforms are increasing our capability to open this type of visual inspection to the ordinary public. Especially the methodologies for virtual manipulation of Cultural Heritage artifacts through RTI are gaining interest. In this context one of the most interesting kind of objects to acquire and virtually explore by means of RTI images are the ancient coins collections. Typically, a coin is a very small artwork, presented to the public from a distance and visible only from one side. Furthermore, coins have a lot of hidden knowledge that is difficult to transfer to the visitors in an easy, effective and understandable manner. What we present is the use of this new multimedia data, RTI images, in the process of digitalization and virtual presentation of the coin collection of the Palazzo Blu Museum (Pisa, Italy). The main goal of the project was to provide an improved access of ordinary people (visitors of the museum or web surfers) to the exposed numismatic materials. The result of this activity is an interactive kiosk that, integrated with the existing traditional museum exhibition, allows the visitors to interact and virtually explore every coin. The interactive presentation system, developed in HTML5 and designed to be deployed either by a museum kiosk or by a web site, is composed by a presentation section and the interactive viewer of the RTI images of each coin. The presentation part contains the description of the project and the organization of the coins into different subsets, using historical and thematic criteria, with the purpose to provide a presentation to a public of ordinary museum visitors. The RTI viewer offers a set of basic functionalities for the virtual manipulation of the coins using high-resolution images produced by RTI techniques. The RTI image of the coin, generated from a set of images acquired from the same point of view but with different lighting conditions, allows the visitor to change the direction of light in real time, making visible and appreciable details otherwise imperceptible. The virtual manipulation is completed by the free navigation on the coin, with basic operations like pan and zoom, and the possibility to flip the coin, to interact with the reverse, and to explore small areas of interest, identified by some hot spots on the surface and associated with text and pictures that provide additional information about the most interesting and important technical, historical and artistic features of the piece. The kiosk is currently installed inside the Museum Palazzo Blu in Pisa, in the exhibition room of the Ottavio Simoneschi's coin collection, and it will be soon loaded on the museum web site.Project(s): V-MUST.NET
2019
Other
Open Access
Augmented reality experience with physical artefacts
Palma G, Cignoni P
This technical report presents a system to improve the engagement of the user in a virtual reality experience using economic, physical copies of real artefacts, made with cheap 3D fabrication technologies. Based on a combination of hardware and software components, the proposed system gives the user the possibility to interact with the physical replica in the virtual environment and to see the appearance of the original artefact. In this way, we overcome the current limitation of the cheap 3D fabrication technologies: a faithful appearance reproduction. Moreover using a consumer device for the real-time hand tracking and a custom electronic controller for the capacitive touch sensing, the system permits the creation of virtual experiences where the user with his hand can change the virtual appearance of the object using a set of personalization actions selectable from a physical 3D printed palette.Project(s): EMOTIVE
Palma G, Cignoni P
This technical report presents a system to improve the engagement of the user in a virtual reality experience using economic, physical copies of real artefacts, made with cheap 3D fabrication technologies. Based on a combination of hardware and software components, the proposed system gives the user the possibility to interact with the physical replica in the virtual environment and to see the appearance of the original artefact. In this way, we overcome the current limitation of the cheap 3D fabrication technologies: a faithful appearance reproduction. Moreover using a consumer device for the real-time hand tracking and a custom electronic controller for the capacitive touch sensing, the system permits the creation of virtual experiences where the user with his hand can change the virtual appearance of the object using a set of personalization actions selectable from a physical 3D printed palette.Project(s): EMOTIVE
See at:
CNR IRIS 
| ISTI Repository | CNR IRIS
2020
Contribution to book
Restricted
Una Loggia digitale al tempo del COVID-19
Palma G, Siotto E
The chapter starts illustrating the conception and evolution of the project "A digital loggia for Raphael and collaborators in Villa Farnesina, Rome" on behalf of the Accademia Nazionale dei Lincei and ISTI-CNR. After it describes the design and development phases of the interactive digital system, how the data were acquired and how the model was created and, finally, offers a guide to the use of the interactive system organized on two levels of detail (http://vcg.isti.cnr.it/farnesina /loggia/).
Palma G, Siotto E
The chapter starts illustrating the conception and evolution of the project "A digital loggia for Raphael and collaborators in Villa Farnesina, Rome" on behalf of the Accademia Nazionale dei Lincei and ISTI-CNR. After it describes the design and development phases of the interactive digital system, how the data were acquired and how the model was created and, finally, offers a guide to the use of the interactive system organized on two levels of detail (http://vcg.isti.cnr.it/farnesina /loggia/).
See at:
CNR IRIS | CNR IRIS | vcg.isti.cnr.it
2020
Contribution to book
Restricted
A digital Loggia at the time of COVID-19
Palma G, Siotto E
The chapter starts illustrating the conception and evolution of the project "A digital loggia for Raphael and collaborators in Villa Farnesina, Rome" on behalf of the Accademia Nazionale dei Lincei and ISTI-CNR. After it describes the design and development phases of the interactive digital system, how the data were acquired and how the model was created and, finally, offers a guide to the use of the interactive system organized on two levels of detail (http://vcg.isti.cnr.it/farnesina /loggia/).
Palma G, Siotto E
The chapter starts illustrating the conception and evolution of the project "A digital loggia for Raphael and collaborators in Villa Farnesina, Rome" on behalf of the Accademia Nazionale dei Lincei and ISTI-CNR. After it describes the design and development phases of the interactive digital system, how the data were acquired and how the model was created and, finally, offers a guide to the use of the interactive system organized on two levels of detail (http://vcg.isti.cnr.it/farnesina /loggia/).
See at:
CNR IRIS | CNR IRIS | vcg.isti.cnr.it
2021
Journal article
Open Access
Augmented virtuality using touch-sensitive 3D-printed objects
Palma G, Perry S, Cignoni P
Virtual reality (VR) technologies have become more and more affordable and popular in the last five years thanks to hardware and software advancements. A critical issue for these technologies is finding paradigms that allow user interactions in ways that are as similar as possible to the real world, bringing physicality into the experience. Current literature has shown, with different experiments, that the mapping of real objects in virtual reality alongside haptic feedback significantly increases the realism of the experience and user engagement, leading to augmented virtuality. In this paper, we present a system to improve engagement in a VR experience using inexpensive, physical, and sensorized copies of real artefacts made with cheap 3D fabrication technologies. Based on a combination of hardware and software components, the proposed system gives the user the possibility to interact with the physical replica in the virtual environment and to see the appearance of the original cultural heritage artefact. In this way, we overcome one of the main limitations of mainstream 3D fabrication technologies: a faithful appearance reproduction. Using a consumer device for the real-time hand tracking and a custom electronic controller for the capacitive touch sensing, the system permits the creation of augmented experiences where the user with their hands can change the virtual appearance of the real replica object using a set of personalization actions selectable from a physical 3D-printed palette.Source: REMOTE SENSING (BASEL), vol. 13 (issue 11)
Project(s): EMOTIVE
Palma G, Perry S, Cignoni P
Virtual reality (VR) technologies have become more and more affordable and popular in the last five years thanks to hardware and software advancements. A critical issue for these technologies is finding paradigms that allow user interactions in ways that are as similar as possible to the real world, bringing physicality into the experience. Current literature has shown, with different experiments, that the mapping of real objects in virtual reality alongside haptic feedback significantly increases the realism of the experience and user engagement, leading to augmented virtuality. In this paper, we present a system to improve engagement in a VR experience using inexpensive, physical, and sensorized copies of real artefacts made with cheap 3D fabrication technologies. Based on a combination of hardware and software components, the proposed system gives the user the possibility to interact with the physical replica in the virtual environment and to see the appearance of the original cultural heritage artefact. In this way, we overcome one of the main limitations of mainstream 3D fabrication technologies: a faithful appearance reproduction. Using a consumer device for the real-time hand tracking and a custom electronic controller for the capacitive touch sensing, the system permits the creation of augmented experiences where the user with their hands can change the virtual appearance of the real replica object using a set of personalization actions selectable from a physical 3D-printed palette.Source: REMOTE SENSING (BASEL), vol. 13 (issue 11)
Project(s): EMOTIVE
See at:
CNR IRIS | ISTI Repository | www.mdpi.com | CNR IRIS
2024
Journal article
Open Access
Capacitive touch sensing on general 3D surfaces
Palma G., Pourjafarian N., Steimle J., Cignoni P.
Mutual-capacitive sensing is the most common technology for detecting multi-touch, especially on flat and simple curvature surfaces. Its extension to a more complex shape is still challenging, as a uniform distribution of sensing electrodes is required for consistent touch sensitivity across the surface. To overcome this problem, we propose a method to adapt the sensor layout of common capacitive multi-touch sensors to more complex 3D surfaces, ensuring high-resolution, robust multi-touch detection. The method automatically computes a grid of transmitter and receiver electrodes with as regular distribution as possible over a general 3D shape. It starts with the computation of a proxy geometry by quad meshing used to place the electrodes through the dual-edge graph. It then arranges electrodes on the surface to minimize the number of touch controllers required for capacitive sensing and the number of input/output pins to connect the electrodes with the controllers. We reach these objectives using a new simplification and clustering algorithm for a regular quad-patch layout. The reduced patch layout is used to optimize the routing of all the structures (surface grooves and internal pipes) needed to host all electrodes on the surface and inside the object's volume, considering the geometric constraints of the 3D shape. Finally, we print the 3D object prototype ready to be equipped with the electrodes. We analyze the performance of the proposed quad layout simplification and clustering algorithm using different quad meshing and characterize the signal quality and accuracy of the capacitive touch sensor for different non-planar geometries. The tested prototypes show precise and robust multi-touch detection with good Signal-to-Noise Ratio and spatial accuracy of about 1mm.Source: ACM TRANSACTIONS ON GRAPHICS, vol. 43 (issue 4)
Palma G., Pourjafarian N., Steimle J., Cignoni P.
Mutual-capacitive sensing is the most common technology for detecting multi-touch, especially on flat and simple curvature surfaces. Its extension to a more complex shape is still challenging, as a uniform distribution of sensing electrodes is required for consistent touch sensitivity across the surface. To overcome this problem, we propose a method to adapt the sensor layout of common capacitive multi-touch sensors to more complex 3D surfaces, ensuring high-resolution, robust multi-touch detection. The method automatically computes a grid of transmitter and receiver electrodes with as regular distribution as possible over a general 3D shape. It starts with the computation of a proxy geometry by quad meshing used to place the electrodes through the dual-edge graph. It then arranges electrodes on the surface to minimize the number of touch controllers required for capacitive sensing and the number of input/output pins to connect the electrodes with the controllers. We reach these objectives using a new simplification and clustering algorithm for a regular quad-patch layout. The reduced patch layout is used to optimize the routing of all the structures (surface grooves and internal pipes) needed to host all electrodes on the surface and inside the object's volume, considering the geometric constraints of the 3D shape. Finally, we print the 3D object prototype ready to be equipped with the electrodes. We analyze the performance of the proposed quad layout simplification and clustering algorithm using different quad meshing and characterize the signal quality and accuracy of the capacitive touch sensor for different non-planar geometries. The tested prototypes show precise and robust multi-touch detection with good Signal-to-Noise Ratio and spatial accuracy of about 1mm.Source: ACM TRANSACTIONS ON GRAPHICS, vol. 43 (issue 4)
See at:
dl.acm.org | CNR IRIS | CNR IRIS | CNR IRIS
2024
Patent
Restricted
Procedimento per fornire un rilevamento del tocco ad alta risoluzione su oggetti 3D
Palma G., Cignoni P., Pourjafarian N., Steimle J.
A computer-implemented method is disclosed for designing a touch sensing arrangement for a 3D object (B), the method includes (i) performing a quad meshing of the surface of the body, the quad mesh including a plurality of quadrangular areas (Q) having side dimensions matching the mutual spacing between pairs of adjacent transmit electrode lines (T) and between pairs of adjacent receive electrode lines (R) of the touch sensing arrangement, (ii) computing a quad patch layout comprising a plurality of quad patches (P), each including a plurality of adjacent quadrangular areas (Q) of the quad mesh, selectively grouping the quad patches (P) in- to a plurality of clusters (C) of adjacent patches (P) and packing the clusters (C) into a plurality of cluster sets, each cluster set being associated with a respective touch controller (TC), wherein the transmit electrode lines (T) and the receive electrode lines (R) of the touch sensing arrange- ment are designed according to a dual edge graph of the quad mesh, and interconnecting conducting paths are established between transmit and receive elec- trode lines (T, R) of each cluster set and the re- spective touch controller (TC) through the internal volume of the object (B).
Palma G., Cignoni P., Pourjafarian N., Steimle J.
A computer-implemented method is disclosed for designing a touch sensing arrangement for a 3D object (B), the method includes (i) performing a quad meshing of the surface of the body, the quad mesh including a plurality of quadrangular areas (Q) having side dimensions matching the mutual spacing between pairs of adjacent transmit electrode lines (T) and between pairs of adjacent receive electrode lines (R) of the touch sensing arrangement, (ii) computing a quad patch layout comprising a plurality of quad patches (P), each including a plurality of adjacent quadrangular areas (Q) of the quad mesh, selectively grouping the quad patches (P) in- to a plurality of clusters (C) of adjacent patches (P) and packing the clusters (C) into a plurality of cluster sets, each cluster set being associated with a respective touch controller (TC), wherein the transmit electrode lines (T) and the receive electrode lines (R) of the touch sensing arrange- ment are designed according to a dual edge graph of the quad mesh, and interconnecting conducting paths are established between transmit and receive elec- trode lines (T, R) of each cluster set and the re- spective touch controller (TC) through the internal volume of the object (B).
2010
Conference article
Open Access
Principles and practices of robust, photography-based digital imaging techniques for museums
Mudge M., Schroer C., Earl G., Martinez K., Pagi H., Toler-Franklin C., Rusinkiewicz S., Palma G., Wachowiak M., Ashley M., Matthews N., Noble T., Dellepiane M.
This full day tutorial will use lectures and demonstrations from leading researchers and museum practitioners to present the principles and practices for robust photography-based digital techniques in museum contexts. The tutorial will present many examples of existing and cutting-edge uses of photography-based imaging including Reflectance Transformation Imaging (RTI), Algorithmic Rendering (AR), camera calibration, and methods of imaged-based generation of textured 3D geometry. Leading museums are now adopting the more mature members of this family of robust digital imaging practices. These practices are part of the emerging science known as Computational Photography (CP). The imaging family's common feature is the purpose-driven selective extraction of information from sequences of standard digital photographs. The information is extracted from the photographic sequences by computer algorithms. The extracted information is then integrated into a new digital representations containing knowledge not present in the original photographs, examined either alone or sequentially. The tutorial will examine strategies that promote widespread museum adoption of empirical acquisition technologies, generate scientifically reliable digital representations that are 'born archival', assist this knowledge's long-term digital preservation, enable its future reuse for novel purposes, aid the physical conservation of the digitally represented museum materials, and enable public access and research.DOI: 10.2312/pe/vast/vast10s/111-137
Metrics:
Mudge M., Schroer C., Earl G., Martinez K., Pagi H., Toler-Franklin C., Rusinkiewicz S., Palma G., Wachowiak M., Ashley M., Matthews N., Noble T., Dellepiane M.
This full day tutorial will use lectures and demonstrations from leading researchers and museum practitioners to present the principles and practices for robust photography-based digital techniques in museum contexts. The tutorial will present many examples of existing and cutting-edge uses of photography-based imaging including Reflectance Transformation Imaging (RTI), Algorithmic Rendering (AR), camera calibration, and methods of imaged-based generation of textured 3D geometry. Leading museums are now adopting the more mature members of this family of robust digital imaging practices. These practices are part of the emerging science known as Computational Photography (CP). The imaging family's common feature is the purpose-driven selective extraction of information from sequences of standard digital photographs. The information is extracted from the photographic sequences by computer algorithms. The extracted information is then integrated into a new digital representations containing knowledge not present in the original photographs, examined either alone or sequentially. The tutorial will examine strategies that promote widespread museum adoption of empirical acquisition technologies, generate scientifically reliable digital representations that are 'born archival', assist this knowledge's long-term digital preservation, enable its future reuse for novel purposes, aid the physical conservation of the digitally represented museum materials, and enable public access and research.DOI: 10.2312/pe/vast/vast10s/111-137
Metrics:
See at:
e-Prints Soton | dblp.uni-trier.de | CNR IRIS | CNR IRIS
2024
Journal article
Metadata Only Access
Touch-Sensing 3D Replica for Augmented Virtuality
Gianpaolo Palma, Paolo Cignoni
We introduce a system designed to enhance engagement in VR experiences using sensorised replicas of real objects created through 3D printing. This system lets users interact with physical replicas within the virtual environment while visualising the original object's appearance. Additionally, it facilitates the creation of augmented experiences to manipulate the virtual appearance of the physical replica using personalisation actions, such as painting over the object’s surface or attaching additional virtual objects, taking advantage of its tactile feedback.Source: ERCIM NEWS, vol. 137, pp. 13-14
Project(s): EMOTIVE
Gianpaolo Palma, Paolo Cignoni
We introduce a system designed to enhance engagement in VR experiences using sensorised replicas of real objects created through 3D printing. This system lets users interact with physical replicas within the virtual environment while visualising the original object's appearance. Additionally, it facilitates the creation of augmented experiences to manipulate the virtual appearance of the physical replica using personalisation actions, such as painting over the object’s surface or attaching additional virtual objects, taking advantage of its tactile feedback.Source: ERCIM NEWS, vol. 137, pp. 13-14
Project(s): EMOTIVE
See at:
CNR IRIS
2017
Contribution to book
Restricted
Realizzazione del sistema interattivo 'Loggia digitale'
Siotto E, Palma G, Scopigno R
The VC Lab has developed, in collaboration with the Accademia Nazionale dei Lincei, the Interactive Digital System of the Loggia of Cupid and Psyche within the exhibition 'The Loggia of Cupid and Psyche - Raffaello and Giovanni da Udine - Colours of Prosperity: Fruits from the Old and New World' Villa Farnesina, Rome April 20 - July 20 2017. The system allows access to the 'digital Loggia' and permits the visitor to navigate freely through the high-resolution panoramic image of the painted ceiling, to admire it from a closer point of view and to consult the results of historical, botanical and scientific analyses performed on the selected species. The system is available online and with an interactive kiosk in the Farnesina building.
Siotto E, Palma G, Scopigno R
The VC Lab has developed, in collaboration with the Accademia Nazionale dei Lincei, the Interactive Digital System of the Loggia of Cupid and Psyche within the exhibition 'The Loggia of Cupid and Psyche - Raffaello and Giovanni da Udine - Colours of Prosperity: Fruits from the Old and New World' Villa Farnesina, Rome April 20 - July 20 2017. The system allows access to the 'digital Loggia' and permits the visitor to navigate freely through the high-resolution panoramic image of the painted ceiling, to admire it from a closer point of view and to consult the results of historical, botanical and scientific analyses performed on the selected species. The system is available online and with an interactive kiosk in the Farnesina building.
See at:
CNR IRIS | CNR IRIS | vcg.isti.cnr.it
2010
Journal article
Restricted
Dynamic shading enhancement for reflectance transformation imaging
Palma G, Corsini M, Cignoni P, Scopigno R, Mudge M
We propose a set of dynamic shading enhancement techniques for improving the perception of details, features, and overall shape characteristics from images created with Reflectance Transformation Imaging (RTI) techniques. Selection of these perceptual enhancement filters can significantly improve the user's ability to interactively inspect the content of 2D RTI media by zooming, panning, and changing the illumination direction. In particular, we present two groups of strategies for RTI image enhancement based on two main ideas: exploiting the unsharp masking methodology in the RTI-specific context; and locally optimizing the incident light direction for improved RTI image sharpness and illumination of surface features. The Result section will present a number of datasets and compare them with existing techniques.Source: ACM JOURNAL ON COMPUTING AND CULTURAL HERITAGE, vol. 3 (issue 2), pp. 1-20
Palma G, Corsini M, Cignoni P, Scopigno R, Mudge M
We propose a set of dynamic shading enhancement techniques for improving the perception of details, features, and overall shape characteristics from images created with Reflectance Transformation Imaging (RTI) techniques. Selection of these perceptual enhancement filters can significantly improve the user's ability to interactively inspect the content of 2D RTI media by zooming, panning, and changing the illumination direction. In particular, we present two groups of strategies for RTI image enhancement based on two main ideas: exploiting the unsharp masking methodology in the RTI-specific context; and locally optimizing the incident light direction for improved RTI image sharpness and illumination of surface features. The Result section will present a number of datasets and compare them with existing techniques.Source: ACM JOURNAL ON COMPUTING AND CULTURAL HERITAGE, vol. 3 (issue 2), pp. 1-20
2017
Contribution to book
Restricted
Development of the interactive system 'digital Loggia'
Siotto E, Palma G, Scopigno R
The VC Lab has developed, in collaboration with the Accademia Nazionale dei Lincei, the Interactive Digital System of the Loggia of Cupid and Psyche within the exhibition 'The Loggia of Cupid and Psyche - Raffaello and Giovanni da Udine - Colours of Prosperity: Fruits from the Old and New World' Villa Farnesina, Rome April 20 - July 20 2017. The system allows access to the 'digital Loggia' and permits the visitor to navigate freely through the high-resolution panoramic image of the painted ceiling, to admire it from a closer point of view and to consult the results of historical, botanical and scientific analyses performed on the selected species. The system is available online and with an interactive kiosk in the Farnesina building.
Siotto E, Palma G, Scopigno R
The VC Lab has developed, in collaboration with the Accademia Nazionale dei Lincei, the Interactive Digital System of the Loggia of Cupid and Psyche within the exhibition 'The Loggia of Cupid and Psyche - Raffaello and Giovanni da Udine - Colours of Prosperity: Fruits from the Old and New World' Villa Farnesina, Rome April 20 - July 20 2017. The system allows access to the 'digital Loggia' and permits the visitor to navigate freely through the high-resolution panoramic image of the painted ceiling, to admire it from a closer point of view and to consult the results of historical, botanical and scientific analyses performed on the selected species. The system is available online and with an interactive kiosk in the Farnesina building.
See at:
CNR IRIS | CNR IRIS | vcg.isti.cnr.it
2010
Conference article
Restricted
Improving 2D-3D registration by mutual information using gradient maps
Palma G, Corsini M, Dellepiane M, Scopigno R
In this paper we propose an extension for the algorithms of image-to-geometry registration by Mutual Information(MI) to improve the performance and the quality of the alignment. Proposed for the registration of multi modal medical images, in the last years MI has been adapted to align a 3D model to a given image by using different renderings of the model and a gray-scale version of the input image. A key aspect is the choice of the rendering process to correlate the 3D model to the image without taking into account the texture data and the lighting conditions. Even if several rendering types for the 3D model have been analyzed, in some cases the alignment fails for two main reasons: the peculiar reflection behavior of the object that we are not able to reproduce in the rendering of the 3D model without knowing the material characteristics of the object and the lighting conditions of the acquisition environment; the characteristics of the image background, especially non uniform background, that can degrade the convergence of the registration. To improve the quality of the registration in these cases we propose to compute the MI between the gradient map of the 3D rendering and the gradient map of the image in order to maximize the shared data between them.
Palma G, Corsini M, Dellepiane M, Scopigno R
In this paper we propose an extension for the algorithms of image-to-geometry registration by Mutual Information(MI) to improve the performance and the quality of the alignment. Proposed for the registration of multi modal medical images, in the last years MI has been adapted to align a 3D model to a given image by using different renderings of the model and a gray-scale version of the input image. A key aspect is the choice of the rendering process to correlate the 3D model to the image without taking into account the texture data and the lighting conditions. Even if several rendering types for the 3D model have been analyzed, in some cases the alignment fails for two main reasons: the peculiar reflection behavior of the object that we are not able to reproduce in the rendering of the 3D model without knowing the material characteristics of the object and the lighting conditions of the acquisition environment; the characteristics of the image background, especially non uniform background, that can degrade the convergence of the registration. To improve the quality of the registration in these cases we propose to compute the MI between the gradient map of the 3D rendering and the gradient map of the image in order to maximize the shared data between them.
2008
Software
Metadata Only Access
RTIViewer - a tool for remote browsing of images created with relectance transformation techniques.
Cignoni P, Corsini M, Palma G, Scopigno R
The RTI Viewer allows you to load and examine images created with relectance transformation techniques. The tool supports these formats, collectively called RTI files: X Polynomial Texture Maps (PTM files) X Hemispherical Harmonics Maps (HSH files) X Universal Reflectance Transformation Imaging (URTI files) The viewer can display both single-view and multi-view images; a mulit-view RTI is a collection of single-view images together with optical flow data that generates intermediate views.
Cignoni P, Corsini M, Palma G, Scopigno R
The RTI Viewer allows you to load and examine images created with relectance transformation techniques. The tool supports these formats, collectively called RTI files: X Polynomial Texture Maps (PTM files) X Hemispherical Harmonics Maps (HSH files) X Universal Reflectance Transformation Imaging (URTI files) The viewer can display both single-view and multi-view images; a mulit-view RTI is a collection of single-view images together with optical flow data that generates intermediate views.
See at:
CNR IRIS
2012
Journal article
Restricted
A statistical method for SVBRDF approximation from video sequences in general lighting conditions
Palma G, Callieri M, Dellepiane M, Scopigno R
We present a statistical method for the estimation of the Spatially Varying Bidirectional Reflectance Distribution Function (SVBRDF) of an object with complex geometry, starting from video sequences acquired with fixed but general lighting conditions. The aim of this work is to define a method that simplifies the acquisition phase of the object surface appearance and allows to reconstruct an approximated SVBRDF. The final output is suitable to be used with a 3D model of the object to obtain accurate and photo-realistic renderings. The method is composed by three steps: the approximation of the environment map of the acquisition scene, using the same object as a probe; the estimation of the diffuse color of the object; the estimation of the specular components of the main materials of the object, by using a Phong model. All the steps are based on statistical analysis of the color samples projected by the video sequences on the surface of the object. Although the method presents some limitations, the trade-off between the easiness of acquisition and the obtained results makes it useful for practical applications.Source: COMPUTER GRAPHICS FORUM (ONLINE), vol. 31 (issue 4), pp. 1491-1500
Project(s): 3D-COFORM
Palma G, Callieri M, Dellepiane M, Scopigno R
We present a statistical method for the estimation of the Spatially Varying Bidirectional Reflectance Distribution Function (SVBRDF) of an object with complex geometry, starting from video sequences acquired with fixed but general lighting conditions. The aim of this work is to define a method that simplifies the acquisition phase of the object surface appearance and allows to reconstruct an approximated SVBRDF. The final output is suitable to be used with a 3D model of the object to obtain accurate and photo-realistic renderings. The method is composed by three steps: the approximation of the environment map of the acquisition scene, using the same object as a probe; the estimation of the diffuse color of the object; the estimation of the specular components of the main materials of the object, by using a Phong model. All the steps are based on statistical analysis of the color samples projected by the video sequences on the surface of the object. Although the method presents some limitations, the trade-off between the easiness of acquisition and the obtained results makes it useful for practical applications.Source: COMPUTER GRAPHICS FORUM (ONLINE), vol. 31 (issue 4), pp. 1491-1500
Project(s): 3D-COFORM
See at:
CNR IRIS | CNR IRIS | onlinelibrary.wiley.com
2012
Conference article
Open Access
Telling the story of ancient coins by means of interactive RTI images visualization
Palma G, Siotto E, Proesmans M, Baldassarri M, Baracchini C, Batino S, Scopigno R
Methodologies for virtual examination of Cultural Heritage artifacts through Reflectance Transformation Imaging (RTI) are gaining interest. Although at the beginning this techniques were designed to aid Cultural Heritage specialists in the inspection and interpretation process, the recent advances of 3D web visualization platforms are increasing our capability to open this type of visual inspection to the ordinary public. We present the design and implementation of a system that provide the access of ordinary people (visitors of the museum or web surfers) to a collection of ancient coins, preserved in the San Matteo Museum of Pisa (Italy). Those coins have been digitized to produce RTI representations and are presented to museum visitors together with some data telling their story and explaining their value. The interactive presentation system, designed to be deployed either by a museum kiosk or by a web site, is composed of two integrated sections: a brief introduction to the different subsets of coins; an interactive visualization of the RTI representation of each coin, by means of a specific RTI viewer. The coins are organized in different (possibly overlapping) subsets, to allow us to better present them to a public of inexperienced visitors. Starting from the main theme, the Historical Collection of the coins, we have some subsets about the iconography, the different production techniques (coining or fusion), the value of the coins, etc. After the selection of a specific subset, the user is presented a basic page containing an hypertext description with some basic information, a draggable image gallery with the thumbnails of the coins in the subset and the RTI viewer to display the specific selected coin. The viewer supports visualization and interaction with the RTI image through a basic set of functionalities: changing the light direction, zooming, panning over the image, flipping the coin to switch between the two sides and finally the possibility to show some hot spots, which link specific locations/areas on the coin with descriptive data (presented by means of HTML hypertext page).
Palma G, Siotto E, Proesmans M, Baldassarri M, Baracchini C, Batino S, Scopigno R
Methodologies for virtual examination of Cultural Heritage artifacts through Reflectance Transformation Imaging (RTI) are gaining interest. Although at the beginning this techniques were designed to aid Cultural Heritage specialists in the inspection and interpretation process, the recent advances of 3D web visualization platforms are increasing our capability to open this type of visual inspection to the ordinary public. We present the design and implementation of a system that provide the access of ordinary people (visitors of the museum or web surfers) to a collection of ancient coins, preserved in the San Matteo Museum of Pisa (Italy). Those coins have been digitized to produce RTI representations and are presented to museum visitors together with some data telling their story and explaining their value. The interactive presentation system, designed to be deployed either by a museum kiosk or by a web site, is composed of two integrated sections: a brief introduction to the different subsets of coins; an interactive visualization of the RTI representation of each coin, by means of a specific RTI viewer. The coins are organized in different (possibly overlapping) subsets, to allow us to better present them to a public of inexperienced visitors. Starting from the main theme, the Historical Collection of the coins, we have some subsets about the iconography, the different production techniques (coining or fusion), the value of the coins, etc. After the selection of a specific subset, the user is presented a basic page containing an hypertext description with some basic information, a draggable image gallery with the thumbnails of the coins in the subset and the RTI viewer to display the specific selected coin. The viewer supports visualization and interaction with the RTI image through a basic set of functionalities: changing the light direction, zooming, panning over the image, flipping the coin to switch between the two sides and finally the possibility to show some hot spots, which link specific locations/areas on the coin with descriptive data (presented by means of HTML hypertext page).
2013
Conference article
Restricted
Surface light field from video acquired in uncontrolled settings
Palma G, Desogus N, Cignoni P, Scopigno R
This paper presents an algorithm for the estimation of the Surface Light Field using video sequences acquired moving the camera around the object. Unlike other state of the art methods, it does not require a uniform sampling density of the view directions, but it is able to build an approximation of the Surface Light Field starting from a biased video acquisition: dense along the camera path and completely missing in the other directions. The main idea is to separate the estimation of two components: the diffuse color, computed using statistical operations that allow the estimation of a rough approximation of the direction of the main light sources in the acquisition environment; the other residual Surface Light Field effects,modeled as linear combination of spherical functions. From qualitative and numerical evaluations, the final rendering results show a high fidelity and similarity with the input video frames, without ringing and banding effects.Project(s): HARVEST4D
Palma G, Desogus N, Cignoni P, Scopigno R
This paper presents an algorithm for the estimation of the Surface Light Field using video sequences acquired moving the camera around the object. Unlike other state of the art methods, it does not require a uniform sampling density of the view directions, but it is able to build an approximation of the Surface Light Field starting from a biased video acquisition: dense along the camera path and completely missing in the other directions. The main idea is to separate the estimation of two components: the diffuse color, computed using statistical operations that allow the estimation of a rough approximation of the direction of the main light sources in the acquisition environment; the other residual Surface Light Field effects,modeled as linear combination of spherical functions. From qualitative and numerical evaluations, the final rendering results show a high fidelity and similarity with the input video frames, without ringing and banding effects.Project(s): HARVEST4D
2014
Other
Restricted
Automatic detection of geometric changes in time varying point clouds
Palma G, Cignoni P, Tamy B, Scopigno R
The detection of the geometric changes in 4D data is an important task for all the applications interested in the segmentation of the input geometry between the static and dynamic areas, for the example the cleaning of the input clouds from the objects that are moved or disappear in one of the time step or the analysis and the study of the dynamic part to model the type of change. In this paper we present a novel algorithm to solve this problem that takes in input two point clouds of the same environments acquired in different moments. The core of the method is the computation of the differences between the point clouds using a multi-scale comparison of the implicit surface defined using the Growing Least Square framework. Then the obtained results are further processed to make the segmentation more robust in some critical geometrical configurations that are very common in man-made environments. The final segmentation shows an accurate detection of the real changes in the scene.Project(s): HARVEST4D
Palma G, Cignoni P, Tamy B, Scopigno R
The detection of the geometric changes in 4D data is an important task for all the applications interested in the segmentation of the input geometry between the static and dynamic areas, for the example the cleaning of the input clouds from the objects that are moved or disappear in one of the time step or the analysis and the study of the dynamic part to model the type of change. In this paper we present a novel algorithm to solve this problem that takes in input two point clouds of the same environments acquired in different moments. The core of the method is the computation of the differences between the point clouds using a multi-scale comparison of the implicit surface defined using the Growing Least Square framework. Then the obtained results are further processed to make the segmentation more robust in some critical geometrical configurations that are very common in man-made environments. The final segmentation shows an accurate detection of the real changes in the scene.Project(s): HARVEST4D