2025
Journal article
Open Access
Craniocaudal mammograms generation using image-to-image translation techniques
Piras V., Bonatti A. F., De Maria C., Cignoni P., Banterle F.
Breast cancer is the leading cause of cancer death in women worldwide, emphasizing the need for prevention and early detection. Mammography screening plays a crucial role in secondary prevention, but large datasets of referred mammograms from hospital databases are hard to access due to privacy concerns, and publicly available datasets are often unreliable and unbalanced. We propose a novel workflow using a statistical generative model based on generative adversarial networks to generate high-resolution synthetic mammograms. Utilizing a unique 2D parametric model of the compressed breast in craniocaudal projection and image-to-image translation techniques, our approach allows full and precise control over breast features and the generation of both normal and tumor cases. Quality assessment was conducted through visual analysis, and statistical analysis using the first five statistical moments. Additionally a questionnaire was administered to 45 medical experts (radiologists and radiology residents). The results showed that the features of the real mammograms were accurately replicated in the synthetic ones, the image statistics overall correspond reasonably well, and the two groups of images were statistically indistinguishable in almost all cases according to the experts. The proposed workflow generates realistic synthetic mammograms with fine-tuned features. Synthetic mammograms are powerful tools that can create new or balance existing datasets, allowing for the training of machine learning and deep learning algorithms. These algorithms can then assist radiologists in tasks like classification and segmentation, improving diagnostic performance. The code and dataset are available at: https://github.com/cnr-isti-vclab/CC-Mammograms-Generation_GUI.Source: IEEE JOURNAL OF BIOMEDICAL AND HEALTH INFORMATICS
DOI: 10.1109/jbhi.2025.3599641
Project(s): "Cloud Computing, Big Data & Cybersecurity” and FoReLab
Metrics:
Piras V., Bonatti A. F., De Maria C., Cignoni P., Banterle F.
Breast cancer is the leading cause of cancer death in women worldwide, emphasizing the need for prevention and early detection. Mammography screening plays a crucial role in secondary prevention, but large datasets of referred mammograms from hospital databases are hard to access due to privacy concerns, and publicly available datasets are often unreliable and unbalanced. We propose a novel workflow using a statistical generative model based on generative adversarial networks to generate high-resolution synthetic mammograms. Utilizing a unique 2D parametric model of the compressed breast in craniocaudal projection and image-to-image translation techniques, our approach allows full and precise control over breast features and the generation of both normal and tumor cases. Quality assessment was conducted through visual analysis, and statistical analysis using the first five statistical moments. Additionally a questionnaire was administered to 45 medical experts (radiologists and radiology residents). The results showed that the features of the real mammograms were accurately replicated in the synthetic ones, the image statistics overall correspond reasonably well, and the two groups of images were statistically indistinguishable in almost all cases according to the experts. The proposed workflow generates realistic synthetic mammograms with fine-tuned features. Synthetic mammograms are powerful tools that can create new or balance existing datasets, allowing for the training of machine learning and deep learning algorithms. These algorithms can then assist radiologists in tasks like classification and segmentation, improving diagnostic performance. The code and dataset are available at: https://github.com/cnr-isti-vclab/CC-Mammograms-Generation_GUI.Source: IEEE JOURNAL OF BIOMEDICAL AND HEALTH INFORMATICS
DOI: 10.1109/jbhi.2025.3599641
Project(s): "Cloud Computing, Big Data & Cybersecurity” and FoReLab
Metrics:
See at:
CNR IRIS 
| ieeexplore.ieee.org | IEEE Journal of Biomedical and Health Informatics 
| CNR IRIS
2025
Contribution to conference
Open Access
NOVA-3DGS: NO-reference objective VAlidation for 3D Gaussian Splatting
Piras V., Bonatti A. F., De Maria C., Cignoni P., Banterle F.
In recent years, radiance field methods, and in particular 3D Gaussian Splatting (3DGS), have distinguished themselves in the field of image-based rendering and scene reconstruction techniques, gaining significant success in academia and being cited in numerous research papers. Like other methods, 3DGS requires a large and diverse dataset of images for network training as a fundamental step to ensure effectiveness and high-quality results. Consequently, the acquisition phase is highly time-consuming, especially considering that a portion of the acquired dataset is not actually used for training but is reserved for testing. This is necessary because all commonly used metrics for evaluating the quality of 3D reconstructions, such as PSNR and SSIM, are reference-based metrics; i.e., requiring a ground truth. In this work, we present NOVA, a study focused on no-reference evaluation of 3DGS renders, based on key metrics in this field: PSNR and SSIM.DOI: 10.2312/egp.20251024
Metrics:
Piras V., Bonatti A. F., De Maria C., Cignoni P., Banterle F.
In recent years, radiance field methods, and in particular 3D Gaussian Splatting (3DGS), have distinguished themselves in the field of image-based rendering and scene reconstruction techniques, gaining significant success in academia and being cited in numerous research papers. Like other methods, 3DGS requires a large and diverse dataset of images for network training as a fundamental step to ensure effectiveness and high-quality results. Consequently, the acquisition phase is highly time-consuming, especially considering that a portion of the acquired dataset is not actually used for training but is reserved for testing. This is necessary because all commonly used metrics for evaluating the quality of 3D reconstructions, such as PSNR and SSIM, are reference-based metrics; i.e., requiring a ground truth. In this work, we present NOVA, a study focused on no-reference evaluation of 3DGS renders, based on key metrics in this field: PSNR and SSIM.DOI: 10.2312/egp.20251024
Metrics:
See at:
diglib.eg.org | CNR IRIS | CNR IRIS
2025
Conference article
Open Access
Inventory-constrained optimization of grid shells driven by reuse
Laccone F., Cignoni P., Malomo L., Giorgi D., Favilli A.
This work presents a novel design approach to enhance grid shell structures using steel beams from dismantled buildings. The objective is to improve grid shell performance with minimal aesthetic changes by minimizing the cut-off waste from reused elements. Given an input grid shell, the optimization combines Integer Linear Programming (ILP), differentiable optimization and graph neural networks to address two key objectives. First, it promotes the use of recycled components from a donor inventory, maximizing the reuse of beams over new elements and minimizing cutting processes. Practically, the target is trying to reuse the beams as-is. Second, it updates the nodal coordinates of the grid shell to reduce a loss function based on strain-energy, improving structural efficiency. Results show topology-preserving shape modifications and global form changes that enhance structural response. Life Cycle Assessment (LCA) confirms the method’s viability as a sustainable development strategy.DOI: 10.1201/9781003658641
Metrics:
Laccone F., Cignoni P., Malomo L., Giorgi D., Favilli A.
This work presents a novel design approach to enhance grid shell structures using steel beams from dismantled buildings. The objective is to improve grid shell performance with minimal aesthetic changes by minimizing the cut-off waste from reused elements. Given an input grid shell, the optimization combines Integer Linear Programming (ILP), differentiable optimization and graph neural networks to address two key objectives. First, it promotes the use of recycled components from a donor inventory, maximizing the reuse of beams over new elements and minimizing cutting processes. Practically, the target is trying to reuse the beams as-is. Second, it updates the nodal coordinates of the grid shell to reduce a loss function based on strain-energy, improving structural efficiency. Results show topology-preserving shape modifications and global form changes that enhance structural response. Life Cycle Assessment (LCA) confirms the method’s viability as a sustainable development strategy.DOI: 10.1201/9781003658641
Metrics:
See at:
CNR IRIS | www.taylorfrancis.com | CNR IRIS
2025
Patent
Restricted
A method for providing high-resolution touch sensing on 3D object
Palma G., Cignoni P., Pourjafarian N., Steimle J.
A computer-implemented method is disclosed for designing a touch sensing arrangement for a 3D ob-ject (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) into 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 arrangement 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 respective 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 ob-ject (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) into 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 arrangement 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 respective touch controller (TC) through the internal volume of the object (B).
2025
Journal article
Open Access
Optimizing free‐form grid shells with reclaimed elements under inventory constraints
Favilli A., Laccone F., Cignoni P., Malomo L., Giorgi D.
We propose a method for designing 3D architectural free-form surfaces, represented as grid shells with beams sourced from inventories of reclaimed elements from dismantled buildings. In inventory-constrained design, the reused elements must be paired with elements in the target design. Traditional solutions to this assignment problem often result in cuts and material waste or geometric distortions that affect the surface aesthetics and buildability. Our method for inventory-constrained assisted design blends the traditional assignment problem with differentiable geometry optimization to reduce cut-off waste while preserving the design intent. Additionally, we extend our approach to incorporate strain energy minimization for structural efficiency. We design differentiable losses that account for inventory, geometry, and structural constraints, and streamline them into a complete pipeline, demonstrated through several case studies. Our approach enables the reuse of existing elements for new designs, reducing the need for sourcing new materials and disposing of waste. Consequently, it can serve as an initial step towards mitigating the significant environmental impact of the construction sector.Source: COMPUTER GRAPHICS FORUM
DOI: 10.1111/cgf.70047
Project(s): Future Artificial Intelligence Research
Metrics:
Favilli A., Laccone F., Cignoni P., Malomo L., Giorgi D.
We propose a method for designing 3D architectural free-form surfaces, represented as grid shells with beams sourced from inventories of reclaimed elements from dismantled buildings. In inventory-constrained design, the reused elements must be paired with elements in the target design. Traditional solutions to this assignment problem often result in cuts and material waste or geometric distortions that affect the surface aesthetics and buildability. Our method for inventory-constrained assisted design blends the traditional assignment problem with differentiable geometry optimization to reduce cut-off waste while preserving the design intent. Additionally, we extend our approach to incorporate strain energy minimization for structural efficiency. We design differentiable losses that account for inventory, geometry, and structural constraints, and streamline them into a complete pipeline, demonstrated through several case studies. Our approach enables the reuse of existing elements for new designs, reducing the need for sourcing new materials and disposing of waste. Consequently, it can serve as an initial step towards mitigating the significant environmental impact of the construction sector.Source: COMPUTER GRAPHICS FORUM
DOI: 10.1111/cgf.70047
Project(s): Future Artificial Intelligence Research
Metrics:
See at:
CNR IRIS | onlinelibrary.wiley.com | CNR IRIS
2025
Contribution to book
Open Access
Designing and developing interactive kiosks for cultural heritage: best practices and common issues
Potenziani M., Callieri M., Cignoni P.
Interactive kiosks are a smart way to engage museum visitors and complement their visiting experience with another layer of engagement and interaction with the artworks. Kiosks are also a perfect complement to an integrated Cultural Heritage project that applies digital technologies for the study, the documentation, and the conservation of works of art, as it might help in adding a new dimension of dissemination and public outreach to the project. The design and development of an interactive kiosk for Cultural Heritage involves very different knowledge, skills, and tools. However, it is possible to find various software components that can be used, with a reasonable effort and a sound strategy, to set up an interactive kiosk able to display complex 2D+ and 3D data and implement advanced interaction paradigms. The aim of this work is to help possible developers, by discussing some working strategies and approaches, highlighting possible tools, and analyzing past activities of kiosk development and deployment.Source: SPRINGER SERIES ON CULTURAL COMPUTING, pp. 473-497
DOI: 10.1007/978-3-031-61018-9_21
Metrics:
Potenziani M., Callieri M., Cignoni P.
Interactive kiosks are a smart way to engage museum visitors and complement their visiting experience with another layer of engagement and interaction with the artworks. Kiosks are also a perfect complement to an integrated Cultural Heritage project that applies digital technologies for the study, the documentation, and the conservation of works of art, as it might help in adding a new dimension of dissemination and public outreach to the project. The design and development of an interactive kiosk for Cultural Heritage involves very different knowledge, skills, and tools. However, it is possible to find various software components that can be used, with a reasonable effort and a sound strategy, to set up an interactive kiosk able to display complex 2D+ and 3D data and implement advanced interaction paradigms. The aim of this work is to help possible developers, by discussing some working strategies and approaches, highlighting possible tools, and analyzing past activities of kiosk development and deployment.Source: SPRINGER SERIES ON CULTURAL COMPUTING, pp. 473-497
DOI: 10.1007/978-3-031-61018-9_21
Metrics:
See at:
CNR IRIS | link.springer.com | CNR IRIS | CNR IRIS | CNR IRIS
2024
Journal article
Open Access
Bending-reinforced grid shells for free-form architectural surfaces
Laccone F, Pietroni N, Cignoni P, Malomo L
We introduce a new method for designing reinforcement for grid shells and improving their resistance to out-of-plane forces inducing bending. The central concept is to support the base network of elements with an additional layer of beams placed at a certain distance from the base surface. We exploit two main techniques to design these structures: first, we derive the orientation of the beam network on a given initial surface forming the grid shell to be reinforced; then, we compute the height of the additional layer that maximizes its overall structural performance. Our method includes a new formulation to derive a smooth direction field that orients the quad remeshing and a novel algorithm that iteratively optimizes the height of the additional layer to minimize the structure's compliance. We couple our optimization strategy with a set of constraints to improve buildability of the network and, simultaneously, preserve the initial surface. We showcase our method on a significant dataset of shapes to demonstrate its applicability to cases where free-form grid shells do not exhibit adequate structural performance due to their geometry.Source: COMPUTER AIDED DESIGN, vol. 168
DOI: 10.1016/j.cad.2023.103670
Metrics:
Laccone F, Pietroni N, Cignoni P, Malomo L
We introduce a new method for designing reinforcement for grid shells and improving their resistance to out-of-plane forces inducing bending. The central concept is to support the base network of elements with an additional layer of beams placed at a certain distance from the base surface. We exploit two main techniques to design these structures: first, we derive the orientation of the beam network on a given initial surface forming the grid shell to be reinforced; then, we compute the height of the additional layer that maximizes its overall structural performance. Our method includes a new formulation to derive a smooth direction field that orients the quad remeshing and a novel algorithm that iteratively optimizes the height of the additional layer to minimize the structure's compliance. We couple our optimization strategy with a set of constraints to improve buildability of the network and, simultaneously, preserve the initial surface. We showcase our method on a significant dataset of shapes to demonstrate its applicability to cases where free-form grid shells do not exhibit adequate structural performance due to their geometry.Source: COMPUTER AIDED DESIGN, vol. 168
DOI: 10.1016/j.cad.2023.103670
Metrics:
See at:
CNR IRIS | www.sciencedirect.com | CNR IRIS | CNR IRIS
2024
Contribution to book
Open Access
Dynamic real-time spatio-temporal acquisition and rendering in adverse environments
Dutta S., Ganovelli F., Cignoni P.
This paper introduces NausicaaVR, a novel hardware/software system designed to acquire and render intricate 3D environments, with a particular emphasis on challenging and adverse contexts. In doing so, we navigate the complex landscape of system calibration and rendering, while seamlessly integrating data from multiple sensors. We explore the distinctive challenges inherent in adverse environments, juxtaposing them against conventional automotive scenarios. Through a comprehensive exposition of all constituent elements of the NausicaaVR system, we offer transparent insights into the encountered obstacles and the intricate decisions that were instrumental in surmounting them. This study seeks to illuminate the developmental trajectory of NausicaaVR and analogous systems, thereby furnishing a repository of knowledge and understanding poised to benefit future research and the pragmatic implementation of such cutting-edge technologies.Source: COMMUNICATIONS IN COMPUTER AND INFORMATION SCIENCE, vol. 2107, pp. 34-53
DOI: 10.1007/978-3-031-60277-1_3
Project(s): NAUtical Safety by means of Integrated Computer-Assisted Appliances 4.0
Metrics:
Dutta S., Ganovelli F., Cignoni P.
This paper introduces NausicaaVR, a novel hardware/software system designed to acquire and render intricate 3D environments, with a particular emphasis on challenging and adverse contexts. In doing so, we navigate the complex landscape of system calibration and rendering, while seamlessly integrating data from multiple sensors. We explore the distinctive challenges inherent in adverse environments, juxtaposing them against conventional automotive scenarios. Through a comprehensive exposition of all constituent elements of the NausicaaVR system, we offer transparent insights into the encountered obstacles and the intricate decisions that were instrumental in surmounting them. This study seeks to illuminate the developmental trajectory of NausicaaVR and analogous systems, thereby furnishing a repository of knowledge and understanding poised to benefit future research and the pragmatic implementation of such cutting-edge technologies.Source: COMMUNICATIONS IN COMPUTER AND INFORMATION SCIENCE, vol. 2107, pp. 34-53
DOI: 10.1007/978-3-031-60277-1_3
Project(s): NAUtical Safety by means of Integrated Computer-Assisted Appliances 4.0
Metrics:
See at:
IRIS Cnr | IRIS Cnr | IRIS Cnr | doi.org | CNR IRIS | 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)
DOI: 10.1145/3658185
Metrics:
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)
DOI: 10.1145/3658185
Metrics:
See at:
IRIS Cnr | IRIS Cnr | IRIS Cnr | ACM Transactions on Graphics | 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.
È descritto un procedimento attuato per mezzo di un elaboratore per progettare una disposizione di rilevamento del tocco per un oggetto 3D (B); il procedimento include (i) la suddivisione in una mesh di quadrilateri della superficie dell'oggetto, la mesh di quadrilateri includendo una pluralità di aree quadrangolari (Q) con lati di dimensioni cor-rispondenti alla distanza reciproca tra coppie di linee di elettrodo di trasmissione (T) adiacenti e tra coppie di linee di elettrodo di ricezione (R) adiacenti della disposizione di rilevamento del tocco, (ii) il calcolo di un layout di patch qua-drilateri comprendente una pluralità di patch qua-drilateri (P), ciascuno dei quali include una plu-ralità di aree quadrangolari adiacenti (Q) della mesh di quadrilateri, raggruppando selettivamente i patch quadrilateri (P) in una pluralità di cluster (C) di patch (P) adiacenti e impacchettando i clu-ster (C) in una pluralità di insiemi di cluster, ogni insieme di cluster essendo associato a un ri-spettivo touch controller (TC), in cui le linee di elettrodo di trasmissione (T) e le linee di elet-trodo di ricezione (R) della disposizione di rile-vamento del tocco sono progettate in base ad un grafo duale della mesh di quadrilateri e vengono stabiliti percorsi conduttivi di interconnessione tra le linee di elettrodo di trasmissione e di ri-cezione (T, R) di ciascun insieme di cluster e il rispettivo touch controller (TC) attraverso il vo-lume interno dell'oggetto (B).
Palma G., Cignoni P., Pourjafarian N., Steimle J.
È descritto un procedimento attuato per mezzo di un elaboratore per progettare una disposizione di rilevamento del tocco per un oggetto 3D (B); il procedimento include (i) la suddivisione in una mesh di quadrilateri della superficie dell'oggetto, la mesh di quadrilateri includendo una pluralità di aree quadrangolari (Q) con lati di dimensioni cor-rispondenti alla distanza reciproca tra coppie di linee di elettrodo di trasmissione (T) adiacenti e tra coppie di linee di elettrodo di ricezione (R) adiacenti della disposizione di rilevamento del tocco, (ii) il calcolo di un layout di patch qua-drilateri comprendente una pluralità di patch qua-drilateri (P), ciascuno dei quali include una plu-ralità di aree quadrangolari adiacenti (Q) della mesh di quadrilateri, raggruppando selettivamente i patch quadrilateri (P) in una pluralità di cluster (C) di patch (P) adiacenti e impacchettando i clu-ster (C) in una pluralità di insiemi di cluster, ogni insieme di cluster essendo associato a un ri-spettivo touch controller (TC), in cui le linee di elettrodo di trasmissione (T) e le linee di elet-trodo di ricezione (R) della disposizione di rile-vamento del tocco sono progettate in base ad un grafo duale della mesh di quadrilateri e vengono stabiliti percorsi conduttivi di interconnessione tra le linee di elettrodo di trasmissione e di ri-cezione (T, R) di ciascun insieme di cluster e il rispettivo touch controller (TC) attraverso il vo-lume interno dell'oggetto (B).
2024
Journal article
Open Access
Procedural generation of geometric patterns for thin shell fabrication
Scandurra E., Laccone F., Malomo L., Callieri M., Cignoni P., Giorgi D.
This paper addresses the design of surface shells as assemblies of tileable, flat geometric patterns with predictable performance in response to mechanical stimuli. We design a family of tileable and fabricable patterns represented as triangle meshes, which can be assembled for creating surface tessellations. First, a regular recursive subdivision of the planar space generates different geometric configurations for candidate patterns, having interesting and varied aesthetic properties. Then, a refinement step addresses manufacturability by solving for non-manifold configurations and sharp angles that would produce disconnected or weak patterns. We devise a strategy for creating continuous variations on the geometry of individual patterns, in both aesthetics and behavior, to enrich the catalog of available designs. Finally, we simulate our patterns to evaluate their mechanical response when loaded in different scenarios targeting out-of-plane bending. Through a simple browsing interface, we show that our patterns span a variety of different bending behaviors. The result is a catalog of patterns with varied aesthetics and predefined mechanical behavior, to use for the direct design of mechanical metamaterials. To assess the feasibility of our design-to-fabricate approach, we show fabricated 3D objects with different curvatures, and compare physical and simulated experiments.Source: COMPUTERS & GRAPHICS, vol. 122 (issue 103958)
DOI: 10.1016/j.cag.2024.103958
Project(s): NextGenerationEU programme under the funding schemes PNRR-PE-AI scheme (M4C2, investment 1.3, line on AI) FAIR (Future Artificial Intelligence Research), Social and hUman ceNtered XR
Metrics:
Scandurra E., Laccone F., Malomo L., Callieri M., Cignoni P., Giorgi D.
This paper addresses the design of surface shells as assemblies of tileable, flat geometric patterns with predictable performance in response to mechanical stimuli. We design a family of tileable and fabricable patterns represented as triangle meshes, which can be assembled for creating surface tessellations. First, a regular recursive subdivision of the planar space generates different geometric configurations for candidate patterns, having interesting and varied aesthetic properties. Then, a refinement step addresses manufacturability by solving for non-manifold configurations and sharp angles that would produce disconnected or weak patterns. We devise a strategy for creating continuous variations on the geometry of individual patterns, in both aesthetics and behavior, to enrich the catalog of available designs. Finally, we simulate our patterns to evaluate their mechanical response when loaded in different scenarios targeting out-of-plane bending. Through a simple browsing interface, we show that our patterns span a variety of different bending behaviors. The result is a catalog of patterns with varied aesthetics and predefined mechanical behavior, to use for the direct design of mechanical metamaterials. To assess the feasibility of our design-to-fabricate approach, we show fabricated 3D objects with different curvatures, and compare physical and simulated experiments.Source: COMPUTERS & GRAPHICS, vol. 122 (issue 103958)
DOI: 10.1016/j.cag.2024.103958
Project(s): NextGenerationEU programme under the funding schemes PNRR-PE-AI scheme (M4C2, investment 1.3, line on AI) FAIR (Future Artificial Intelligence Research), Social and hUman ceNtered XR
Metrics:
See at:
Computers & Graphics | IRIS Cnr | IRIS Cnr | CNR IRIS
2024
Journal article
Open Access
Digital methods and techniques for reconstructing and visualizing ancient 3D polychromy – An overview
Siotto E., Cignoni P.
The digital technologies employed in archaeology since the 1990s have progressively and experimentally been utilized over the last two decades to document and re-present the ancient polychromy of Greek and Roman marble artworks. Given that this remains a developing field of investigation and application, this study offers, for the first time, a systematic review of the endeavours undertaken thus far in implementing information technology for the documentation, analysis, reconstruction, visualization, and presentation of ancient polychromy. This overview is supported by a literature review and existing implementations, organized into methods and techniques employed for 3D colour preservation, analysis, and reconstruction, as well as those used for the visualization and dissemination of findings. The goal is to identify gaps and provide intriguing insights for future research concerning the use of digital technologies as an essential tool in the stages of documenting and disseminating ancient polychromy in architecture and archaeological artefacts. This, in turn, aims to encourage data sharing, contribute to the dissemination of science-based knowledge and resolve substantial barriers associated with the long-term retention of digital data.Source: JOURNAL OF CULTURAL HERITAGE, vol. 68, pp. 59-85
DOI: 10.1016/j.culher.2024.05.002
Metrics:
Siotto E., Cignoni P.
The digital technologies employed in archaeology since the 1990s have progressively and experimentally been utilized over the last two decades to document and re-present the ancient polychromy of Greek and Roman marble artworks. Given that this remains a developing field of investigation and application, this study offers, for the first time, a systematic review of the endeavours undertaken thus far in implementing information technology for the documentation, analysis, reconstruction, visualization, and presentation of ancient polychromy. This overview is supported by a literature review and existing implementations, organized into methods and techniques employed for 3D colour preservation, analysis, and reconstruction, as well as those used for the visualization and dissemination of findings. The goal is to identify gaps and provide intriguing insights for future research concerning the use of digital technologies as an essential tool in the stages of documenting and disseminating ancient polychromy in architecture and archaeological artefacts. This, in turn, aims to encourage data sharing, contribute to the dissemination of science-based knowledge and resolve substantial barriers associated with the long-term retention of digital data.Source: JOURNAL OF CULTURAL HERITAGE, vol. 68, pp. 59-85
DOI: 10.1016/j.culher.2024.05.002
Metrics:
See at:
Journal of Cultural Heritage | IRIS Cnr | IRIS Cnr | CNR IRIS
2024
Conference article
Open Access
Single-instance, multi-target learning of 3D architectural gridshells for material reuse and circular economy
Favilli A., Laccone F., Cignoni P., Malomo L., Giorgi D.
We propose a learning-based method for the assisted design of 3D architectural free-form gridshells which reuse elements from dismantled, old buildings. Given a gridshell design as input, the output is a learned gridshell whose shape has been modified to reuse as many stock elements as possible, while preserving the design intent and optimizing for statics performance. The main idea is to perform multi-target shape optimization as a single-instance machine learning task, featuring differentiable losses that account for both structural and stock constraints. Since our approach enables the reuse of existing elements for new designs, it reduces the need for sourcing new materials and for disposing waste. Therefore, it contributes to switch to a circular economy and alleviate the environmental impact of the construction sector. © 2024 Copyright for this paper by its authors.Source: CEUR WORKSHOP PROCEEDINGS, vol. 3762, pp. 470-475. Naples, Italy, 29-30/05/2024
Project(s): NextGenerationEU programme under the funding schemes PNRR-PE-AI scheme (M4C2, investment 1.3, line on AI) FAIR (Future Artificial Intelligence Research)
Favilli A., Laccone F., Cignoni P., Malomo L., Giorgi D.
We propose a learning-based method for the assisted design of 3D architectural free-form gridshells which reuse elements from dismantled, old buildings. Given a gridshell design as input, the output is a learned gridshell whose shape has been modified to reuse as many stock elements as possible, while preserving the design intent and optimizing for statics performance. The main idea is to perform multi-target shape optimization as a single-instance machine learning task, featuring differentiable losses that account for both structural and stock constraints. Since our approach enables the reuse of existing elements for new designs, it reduces the need for sourcing new materials and for disposing waste. Therefore, it contributes to switch to a circular economy and alleviate the environmental impact of the construction sector. © 2024 Copyright for this paper by its authors.Source: CEUR WORKSHOP PROCEEDINGS, vol. 3762, pp. 470-475. Naples, Italy, 29-30/05/2024
Project(s): NextGenerationEU programme under the funding schemes PNRR-PE-AI scheme (M4C2, investment 1.3, line on AI) FAIR (Future Artificial Intelligence Research)
See at:
ceur-ws.org | CNR IRIS | CNR IRIS
2024
Software
Restricted
TagLab 2024.12.2
Corsini M., Pavoni G., Ponchio F., Muntoni A., Saraceni Q., Cignoni P.
TagLab is an AI-powered segmentation software designed to support the analysis of large orthographic images generated through the photogrammetric pipeline.DOI: 10.5281/zenodo.14258304
Metrics:
Corsini M., Pavoni G., Ponchio F., Muntoni A., Saraceni Q., Cignoni P.
TagLab is an AI-powered segmentation software designed to support the analysis of large orthographic images generated through the photogrammetric pipeline.DOI: 10.5281/zenodo.14258304
Metrics:
See at:
CNR IRIS | CNR IRIS | taglab.isti.cnr.it
2024
Journal article
Open Access
3D imaging application to the study of the early Neolithic ceramic complex: the decorated pottery of Rio Tana (Abruzzi, Italy)
Petrinelli Pannocchia C., Vassanelli A., Terranova A., Potenziani M., Pingi P., Callieri M., Cignoni P.
This study aims to demonstrate the potential of 3D analysis in the study of prehistoric ceramic complexes. Due to the production systems used, prehistoric pottery decorations can vary significantly. Examining the frequency of various decorative methods used at different sites may help identify areas potentially connected to specific traditional elements. However, this is usually a cumbersome and time-consuming task. 3D digital methodologies can bring several advantages in the interpretation of ceramic decoration, providing newtools that can improve analytical skills, speed up the decision process, and support the researcher’s conclusions. This work focuses on the application of these methodologies to the study of decorated ceramics from the Neolithic site of Rio Tana (Abruzzo, central Italy): firstly, a pottery complex from this site has been 3D digitised; then, an interactive and web-based 3D visualisation system has been developed to enable access and study of these digital data. By comparing archaeological data with experimental data, in parallel with the analysis of 3D models’ surfaces, it has been possible to better define the technique employed and quickly identify the type of tool used to create the ceramic decorations. Furthermore, the web-based system made it possible to share and disseminate the digital dataset with the community, creating the conditions to make it easier to compare the frequency of different decoration methods and tools used at Rio Tana with other sites.Source: THE EUROPEAN PHYSICAL JOURNAL PLUS, vol. 139 (issue 6)
DOI: 10.1140/epjp/s13360-024-05198-9
Metrics:
Petrinelli Pannocchia C., Vassanelli A., Terranova A., Potenziani M., Pingi P., Callieri M., Cignoni P.
This study aims to demonstrate the potential of 3D analysis in the study of prehistoric ceramic complexes. Due to the production systems used, prehistoric pottery decorations can vary significantly. Examining the frequency of various decorative methods used at different sites may help identify areas potentially connected to specific traditional elements. However, this is usually a cumbersome and time-consuming task. 3D digital methodologies can bring several advantages in the interpretation of ceramic decoration, providing newtools that can improve analytical skills, speed up the decision process, and support the researcher’s conclusions. This work focuses on the application of these methodologies to the study of decorated ceramics from the Neolithic site of Rio Tana (Abruzzo, central Italy): firstly, a pottery complex from this site has been 3D digitised; then, an interactive and web-based 3D visualisation system has been developed to enable access and study of these digital data. By comparing archaeological data with experimental data, in parallel with the analysis of 3D models’ surfaces, it has been possible to better define the technique employed and quickly identify the type of tool used to create the ceramic decorations. Furthermore, the web-based system made it possible to share and disseminate the digital dataset with the community, creating the conditions to make it easier to compare the frequency of different decoration methods and tools used at Rio Tana with other sites.Source: THE EUROPEAN PHYSICAL JOURNAL PLUS, vol. 139 (issue 6)
DOI: 10.1140/epjp/s13360-024-05198-9
Metrics:
See at:
The European Physical Journal Plus | IRIS Cnr | IRIS Cnr | CNR IRIS
2024
Conference article
Open Access
A study on the use of high dynamic range imaging for gaussian splatting methods: are 8 bits enough?
Piras V., Bonatti A. F., De Maria C., Cignoni P., Banterle F.
The recent rise of Neural Radiance Fields (NeRFs)-like methods has revolutionized high-fidelity scene reconstruction, with 3D Gaussian Splatting (3DGS) standing out for its ability to generate photorealistic images while maintaining fast, efficient rendering. 3DGS delivers high-fidelity representations of complex scenes at any scale (from very small objects to entire cities), accurately capturing geometry, materials, and lighting, while meeting the need for fast and efficient rendering-crucial for applications requiring real-time performance. Although High Dynamic Range (HDR) technology, which enables the capture of comprehensive real-world lighting information, has been used in novel view synthesis, several questions remain unanswered. For example, does HDR improve the overall quality of reconstruction? Are 8 bits enough? Can tone mapped images be a balanced compromise regarding quality and details? To answer such questions, in this work, we study the application of HDR technology on the 3DGS method for acquiring real-world scenes.DOI: 10.2312/stag.20241341
Project(s): Future-Oriented REsearch LABoratory
Metrics:
Piras V., Bonatti A. F., De Maria C., Cignoni P., Banterle F.
The recent rise of Neural Radiance Fields (NeRFs)-like methods has revolutionized high-fidelity scene reconstruction, with 3D Gaussian Splatting (3DGS) standing out for its ability to generate photorealistic images while maintaining fast, efficient rendering. 3DGS delivers high-fidelity representations of complex scenes at any scale (from very small objects to entire cities), accurately capturing geometry, materials, and lighting, while meeting the need for fast and efficient rendering-crucial for applications requiring real-time performance. Although High Dynamic Range (HDR) technology, which enables the capture of comprehensive real-world lighting information, has been used in novel view synthesis, several questions remain unanswered. For example, does HDR improve the overall quality of reconstruction? Are 8 bits enough? Can tone mapped images be a balanced compromise regarding quality and details? To answer such questions, in this work, we study the application of HDR technology on the 3DGS method for acquiring real-world scenes.DOI: 10.2312/stag.20241341
Project(s): Future-Oriented REsearch LABoratory
Metrics:
See at:
diglib.eg.org | CNR IRIS | CNR IRIS
2024
Journal article
Open Access
Integrating widespread coral reef monitoring tools for managing both area and point annotations
Pavoni G., Pierce J., Edwards C. B., Corsini M., Petrovic V., Cignoni P.
Large-area image acquisition techniques are essential in underwater investigations: high-resolution 3D image-based reconstructions have improved coral reef monitoring by enabling novel seascape ecological analysis. Artificial intelligence (AI) offers methods for significantly accelerating image data interpretation, such as automatically recognizing, enumerating, and measuring organisms. However, the rapid proliferation of these technological achievements has led to a relative lack of standardization of methods. Remarkably, there are notable differences in procedures for generating human and AI annotations, and there is also a scarcity of publicly available datasets and shared machine-learning models. The lack of standard procedures makes it challenging to compare and reproduce scientific findings. One way to overcome this problem is to make the most used platforms by coral reef scientists interoperable so that the analyses can all be exported into a common format. This paper introduces functionality to promote interoperability between three popular open-source software tools dedicated to the digital study of coral reefs: TagLab, CoralNet, and Viscore. As users of each platform may have different analysis pipelines, we discuss several workflows for managing and processing point and area annotations, improving collaboration among these tools. Our work sets the foundation for a more seamless ecosystem that maintains the established investigation procedures of various laboratories but allows for easier result sharing.Source: INTERNATIONAL ARCHIVES OF THE PHOTOGRAMMETRY, REMOTE SENSING AND SPATIAL INFORMATION SCIENCES, vol. XLVIII-2-2024 (issue 2), pp. 327-333
DOI: 10.5194/isprs-archives-xlviii-2-2024-327-2024
Project(s): ReefSurvAI: Verso un’infrastruttura web che supporti l’uso dell’intelligenza artificiale per il monitoraggio delle barriere coralline
Metrics:
Pavoni G., Pierce J., Edwards C. B., Corsini M., Petrovic V., Cignoni P.
Large-area image acquisition techniques are essential in underwater investigations: high-resolution 3D image-based reconstructions have improved coral reef monitoring by enabling novel seascape ecological analysis. Artificial intelligence (AI) offers methods for significantly accelerating image data interpretation, such as automatically recognizing, enumerating, and measuring organisms. However, the rapid proliferation of these technological achievements has led to a relative lack of standardization of methods. Remarkably, there are notable differences in procedures for generating human and AI annotations, and there is also a scarcity of publicly available datasets and shared machine-learning models. The lack of standard procedures makes it challenging to compare and reproduce scientific findings. One way to overcome this problem is to make the most used platforms by coral reef scientists interoperable so that the analyses can all be exported into a common format. This paper introduces functionality to promote interoperability between three popular open-source software tools dedicated to the digital study of coral reefs: TagLab, CoralNet, and Viscore. As users of each platform may have different analysis pipelines, we discuss several workflows for managing and processing point and area annotations, improving collaboration among these tools. Our work sets the foundation for a more seamless ecosystem that maintains the established investigation procedures of various laboratories but allows for easier result sharing.Source: INTERNATIONAL ARCHIVES OF THE PHOTOGRAMMETRY, REMOTE SENSING AND SPATIAL INFORMATION SCIENCES, vol. XLVIII-2-2024 (issue 2), pp. 327-333
DOI: 10.5194/isprs-archives-xlviii-2-2024-327-2024
Project(s): ReefSurvAI: Verso un’infrastruttura web che supporti l’uso dell’intelligenza artificiale per il monitoraggio delle barriere coralline
Metrics:
See at:
The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences | The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences | IRIS Cnr | IRIS Cnr | CNR IRIS | Copernicus Publications
2024
Conference article
Open Access
Constrained shape optimization of grid shells based on deep learning
Favilli A., Laccone F., Cignoni P., Malomo L., Giorgi D.
Designing grid shells requires finding a happy medium between aesthetics and engineering quality: architects and structural engineers join efforts to define geometries and grid topologies that achieve structural efficiency. In sculptural architecture, the artistic intent prevails, and produces freeform shapes with possibly large openings to create spectacular effects. This calls for shape optimization methods to mitigate inefficiency caused by bending forces. However, if modifications are not bounded, optimization may either alter the surface aesthetics or violate design constraints. This paper implements a shape optimization method that improves the performance of triangular grid shells while ensuring small shape changes. A graph neural network learns to update the nodal coordinates of the grid shell and reduce both strain-energy, as a measure of structural efficiency, and the total weight of the structure, as a measure of sustainability. Our case studies include regular shapes among the baseline structures of the FreeGrid benchmark, as well as non-conventional geometries.Project(s): Future Artificial Intelligence Research
Favilli A., Laccone F., Cignoni P., Malomo L., Giorgi D.
Designing grid shells requires finding a happy medium between aesthetics and engineering quality: architects and structural engineers join efforts to define geometries and grid topologies that achieve structural efficiency. In sculptural architecture, the artistic intent prevails, and produces freeform shapes with possibly large openings to create spectacular effects. This calls for shape optimization methods to mitigate inefficiency caused by bending forces. However, if modifications are not bounded, optimization may either alter the surface aesthetics or violate design constraints. This paper implements a shape optimization method that improves the performance of triangular grid shells while ensuring small shape changes. A graph neural network learns to update the nodal coordinates of the grid shell and reduce both strain-energy, as a measure of structural efficiency, and the total weight of the structure, as a measure of sustainability. Our case studies include regular shapes among the baseline structures of the FreeGrid benchmark, as well as non-conventional geometries.Project(s): Future Artificial Intelligence Research
See at:
CNR IRIS | www.ingentaconnect.com | CNR IRIS
2024
Software
Open Access
RelightLab 2024.11
Ponchio F., Potenziani M., Muntoni A., Cignoni P.
Relight is a library to create and view (on the web) relightable images (RTI), It supports Polinomial Texture Mapping (PTM), Hemispherical Harmonics (HSH) along with a new Principal Component Analysis (PCA) + Radial Basis Function (RBF) based algorithm with better fidelity (for the same cost and space). It also supports RTI (and image) streamed tiled viewing based on DeepZoom, Google, Zoomify, IIP formats.DOI: 10.5281/zenodo.14196912
Metrics:
Ponchio F., Potenziani M., Muntoni A., Cignoni P.
Relight is a library to create and view (on the web) relightable images (RTI), It supports Polinomial Texture Mapping (PTM), Hemispherical Harmonics (HSH) along with a new Principal Component Analysis (PCA) + Radial Basis Function (RBF) based algorithm with better fidelity (for the same cost and space). It also supports RTI (and image) streamed tiled viewing based on DeepZoom, Google, Zoomify, IIP formats.DOI: 10.5281/zenodo.14196912
Metrics:
See at:
CNR IRIS | vcg.isti.cnr.it | CNR IRIS
2024
Journal article
Open Access
Computational design of segmented concrete shells made of post-tensioned precast flat tiles
Laccone Francesco, Menicagli Sandro, Cignoni Paolo, Malomo Luigi
This paper introduces a novel structural concept for free-form shells, in which the shape is decomposed into flat concrete tiles to be assembled sequentially with the help of falseworks. All tiles can be prefabricated in the shop with an adaptable and reusable molding system. Once the assembly is completed, the tiles are post-tensioned through a network of cables to minimize tension and avoid detachment. The top surface can finally be completed with an in situ cast layer that fills the gaps and activates the entire shell behavior. In contrast, the bottom surface maintains a jagged aesthetics. The paper presents the automatic pipeline supporting the computational design of these shells, from an input shape to its fabrication. The segmentation of the input shape is guided by a field-aligned quad mesh derived from the principal stresses of the thin shell. The tiles are flattened individually and extruded along the normal of the best-fitting plane. In this configuration, only edge midpoints of adjacent tiles share a contact point. Thus, forces can mainly flow along the tiles’ cross directions. The best configuration of cable paths and pre-loads is found by solving a constrained optimization problem exploiting a reduced model of the shell as a network of beams. Six different input shapes are tested to demonstrate the applicability of the proposed design method. The working hypotheses are validated through a higher-resolution nonlinear Finite Element Analysis. The fabrication pipeline is assessed utilizing a reduced-scale 3D-printed replica.Source: STRUCTURES, vol. 62 (issue 106156)
DOI: 10.1016/j.istruc.2024.106156
Metrics:
Laccone Francesco, Menicagli Sandro, Cignoni Paolo, Malomo Luigi
This paper introduces a novel structural concept for free-form shells, in which the shape is decomposed into flat concrete tiles to be assembled sequentially with the help of falseworks. All tiles can be prefabricated in the shop with an adaptable and reusable molding system. Once the assembly is completed, the tiles are post-tensioned through a network of cables to minimize tension and avoid detachment. The top surface can finally be completed with an in situ cast layer that fills the gaps and activates the entire shell behavior. In contrast, the bottom surface maintains a jagged aesthetics. The paper presents the automatic pipeline supporting the computational design of these shells, from an input shape to its fabrication. The segmentation of the input shape is guided by a field-aligned quad mesh derived from the principal stresses of the thin shell. The tiles are flattened individually and extruded along the normal of the best-fitting plane. In this configuration, only edge midpoints of adjacent tiles share a contact point. Thus, forces can mainly flow along the tiles’ cross directions. The best configuration of cable paths and pre-loads is found by solving a constrained optimization problem exploiting a reduced model of the shell as a network of beams. Six different input shapes are tested to demonstrate the applicability of the proposed design method. The working hypotheses are validated through a higher-resolution nonlinear Finite Element Analysis. The fabrication pipeline is assessed utilizing a reduced-scale 3D-printed replica.Source: STRUCTURES, vol. 62 (issue 106156)
DOI: 10.1016/j.istruc.2024.106156
Metrics:
See at:
IRIS Cnr | IRIS Cnr | IRIS Cnr | Structures | CNR IRIS | CNR IRIS