Trabajo presentado en el 46th Computer Applications and Quantitative Methods in Archaeology Confe... more Trabajo presentado en el 46th Computer Applications and Quantitative Methods in Archaeology Conference (CAA 2018), celebrado en Tubingen (Alemania), del 19 al 23 de marzo de 2018
In the last years there is a growing demand of multimodal medical rendering systems able to visua... more In the last years there is a growing demand of multimodal medical rendering systems able to visualize simultaneously data coming from different sources. This paper addresses the Direct Volume Rendering (DVR) of aligned multimodal data in medical applications. Specifically, it proposes a hierarchical representation of the multimodal data set based on the construction of a Fusion Decision Tree (FDT) that, together with a run-length encoding of the non-empty data, provides means of efficiently accessing to the data. Three different implementations of these structures are proposed. The simulations results show that the traversal of the data is fast and that the method is suitable when interactive modifications of the fusion parameters are required.
Volume rendering is a very active research field in Computer Graphics because of its wide range o... more Volume rendering is a very active research field in Computer Graphics because of its wide range of applications in various sciences, from medicine to flow mechanics. In this report, we survey a state-of-the-art on time-varying volume rendering. We state several basic concepts and then we establish several criteria to classify the studied works: IVR versus DVR, 4D versus 3D+time, compression techniques, involved architectures, use of parallelism and image-space versus objectspace coherence. We also address other related problems as transfer functions and 2D cross-sections computation of time-varying volume data. All the papers reviewed are classified into several tables based on the mentioned classification and, finally, several conclusions are presented.
Abstract: Skeletons are compact shape descriptions of discrete images. They have been extensively... more Abstract: Skeletons are compact shape descriptions of discrete images. They have been extensively studied because of their utility in various applications such as data compression, shape abstraction, navigation and features detection. In this article, a new Euclidean skeletal definition for 2D discrete objects based on the Distance Map (DMAT) is being proposed. As a novel feature, it is shown that this skeleton is a connected subset of the discretization of the continuous medial axis of the object....
Proc. 7th International Fall Workshop Vision, …, 2002
This paper addresses the rendering of aligned regular multimodal datasets. It presents a general ... more This paper addresses the rendering of aligned regular multimodal datasets. It presents a general framework of multimodal data fusion that includes several data merging methods. We also analyze the requirements of a rendering system able to provide these different fusion methods. On the basis of these requirements, we propose a novel design for a multimodal rendering system. The design has been implemented and proved showing to be efficient and flexible.
Conferencia de la Asociacion Espanola para la Inteligencia Artificial, 2005
Abstract. This paper analyzes how to introduce machine learning algorithms into the process of di... more Abstract. This paper analyzes how to introduce machine learning algorithms into the process of direct volume rendering. A conceptual framework for the optical property function elicitation process is proposed and particularized for the use of attribute-value classifiers. The process is evaluated in terms of accuracy and speed using four different off-theshelf classifiers (J48, Nave Bayes, Simple Logistic and ECOC-Adaboost). The empirical results confirm the classification of biomedical datasets as a tough problem where an opportunity ...
The manufacturing domain is regarded as one of the most important engineering areas. Recently, sm... more The manufacturing domain is regarded as one of the most important engineering areas. Recently, smart manufacturing merges the use of sensors, intelligent controls, and software to manage each stage in the manufacturing lifecycle. Additionally, the increasing use of point clouds to model real products and machining tools in a virtual space facilitates the more accurate monitoring of the end-to-end production lifecycle. Thus, the conjunction of both, intelligent methods and more accurate 3D models allows the prediction of uncertainties and anomalies in the manufacturing process as well as reduces the final production costs. However, the high complexity of the geometrical structures defined by point clouds and the high accuracy required by the Quality Assurance/Quality control parameters during the process, pave the way for continuous improvements in smart manufacturing methods. This paper addresses a comprehensive analysis of machining tool identification utilizing temporal point clou...
Volume rendering is a very active research field in Computer Graphics because of its wide range o... more Volume rendering is a very active research field in Computer Graphics because of its wide range of applications in various sciences, from medicine to flow mechanics. In this report, we survey a state-of-the-art on time-varying volume rendering. We state several basic concepts and then we establish several criteria to classify the studied works: IVR versus DVR, 4D versus 3D+time, compression techniques, involved architectures, use of parallelism and image-space versus objectspace coherence. We also address other related problems as transfer functions and 2D cross-sections computation of time-varying volume data. All the papers reviewed are classified into several tables based on the mentioned classification and, finally, several conclusions are presented.
International Conference in Central Europe on Computer Graphics and Visualization, 2004
Hybrid rendering of volume and polygonal model is an interesting feature of visualization systems... more Hybrid rendering of volume and polygonal model is an interesting feature of visualization systems, since it helps users to better understand the relationships between internal structures of the volume and fitted surfaces as well as external surfaces. Most of the existing bibliography focuses at the problem of correctly integrating in depth both types of information. The rendering method proposed in
International Conference on Pattern Recognition, 2000
The 3D reconstruction of the cerebral vascular anatomy can greatly improve the diagnosis of vascu... more The 3D reconstruction of the cerebral vascular anatomy can greatly improve the diagnosis of vascular pathologies, such as embolisms and haemorrhages. This paper presents a new method for the automatic extraction of the blood vessels surface and the labelling of its features, specifically branching, aneurysms and stenoses. The method works with segmented magnetic resonance angiography images. It extracts a discrete
Abstract. This paper analyzes how to introduce machine learning algorithms into the process of di... more Abstract. This paper analyzes how to introduce machine learning algorithms into the process of direct volume rendering. A conceptual framework for the optical property function elicitation process is proposed and particularized for the use of attribute-value classifiers. The process is evaluated in terms of accuracy and speed using four different off-theshelf classifiers (J48, Naıve Bayes, Simple Logistic and ECOC-Adaboost). The empirical results confirm the classification of biomedical datasets as a tough problem where an opportunity ...
An interactive cerebral blood vessel exploration system is described. It has been designed on the... more An interactive cerebral blood vessel exploration system is described. It has been designed on the basis of neurosurgeon's requirements in order t,o assist them in the diagnosis of vascular pathologies. The system is based on the construction of a symbolic model of the vascular tree with an automatic identification and labelling of vessel bifurcations, aneurysms and stenoses. It provides several types of visualization: individual MRA slices, MIP, shaded rendermg, symbolic scheme and surface reconstruction.
This paper describes a 3D tool machining simulation system. The initial tool and the grinding whe... more This paper describes a 3D tool machining simulation system. The initial tool and the grinding wheels are integrated with the machine tool. The application reads and interprets the CNC program code that controls the machine, it computes the positions and the motion of ...
... processing. Most of the modeling and visualization systems referenced in the bibliography (Vo... more ... processing. Most of the modeling and visualization systems referenced in the bibliography (VolVis [29], 3D Viewnix [30], BOB [31]) use a quick simplified default visualization for the interaction. ... 31. ChinPurcell, K., BOB: brick of bytes. ...
Direct cell-to-cell volume visualization algorithms, also called projective rendering methods, pr... more Direct cell-to-cell volume visualization algorithms, also called projective rendering methods, present the advantage of allowing semi-transparencies and, additionally, as they project all the samples, they avoid the voxel-space aliasing. However, they are generally computationally expensive and artifacts may appear in the projection. In this paper, different projective strategies are reviewed and compared. A new algorithm, based on a back-to-front (BTF)
This paper addresses the simulation of drilling tools CNC machining. It describes a novel approac... more This paper addresses the simulation of drilling tools CNC machining. It describes a novel approach for the computation of the boundary representation of the machined tools. Machining consists of a sequence of boolean operations of difference between the tool and the grinding wheels through time. The proposed method performs the dynamic boolean operations on cross sections of the tool and it reconstructs the 3Dmodel by tiling between the cross sections. The method is based on classical computational geometry algorithms such as intersection tests, hull computations, 2D boolean operations and surface tiling. This approach is efficient and it provides user control on the resolution of the operations.
This paper introduces a machine learning approach into the process of direct volume rendering of ... more This paper introduces a machine learning approach into the process of direct volume rendering of biomedical highresolution 3D images. More concretely, it proposes a learning pipeline process that generates the classification function within the optical property function used for rendering. Briefly, this pipeline starts with a data acquisition and selection task, it is followed by a feature extraction process, to be ended with sequence of supervised learning steps. Learning comprises Gentle Boost and CRF (Conditional Random Fields) ...
The goal of this paper is the proposal and evaluation of a ray-casting strategy that takes advant... more The goal of this paper is the proposal and evaluation of a ray-casting strategy that takes advantage of the spatial and temporal coherence in image-space as well as in object-space in order to speed up rendering. It is based on a double structure: in image-space, a temporal buffer that stores for each pixel the next instant of time in which the pixel must be recomputed, and in object-space a Temporal Run-Length Encoding of the voxel values through time. The algorithm skips empty and unchanged pixels through three different spaceleaping strategies. It can compute the images sequentially in time or generate them simultaneously in batch. In addition, it can handle simultaneously several data modalities. Finally, an on-purpose out-of-core strategy is used to handle large datasets. The tests performed on two medical datasets and various phantom datasets show that the proposed strategy significantly speeds-up rendering.
Trabajo presentado en el 46th Computer Applications and Quantitative Methods in Archaeology Confe... more Trabajo presentado en el 46th Computer Applications and Quantitative Methods in Archaeology Conference (CAA 2018), celebrado en Tubingen (Alemania), del 19 al 23 de marzo de 2018
In the last years there is a growing demand of multimodal medical rendering systems able to visua... more In the last years there is a growing demand of multimodal medical rendering systems able to visualize simultaneously data coming from different sources. This paper addresses the Direct Volume Rendering (DVR) of aligned multimodal data in medical applications. Specifically, it proposes a hierarchical representation of the multimodal data set based on the construction of a Fusion Decision Tree (FDT) that, together with a run-length encoding of the non-empty data, provides means of efficiently accessing to the data. Three different implementations of these structures are proposed. The simulations results show that the traversal of the data is fast and that the method is suitable when interactive modifications of the fusion parameters are required.
Volume rendering is a very active research field in Computer Graphics because of its wide range o... more Volume rendering is a very active research field in Computer Graphics because of its wide range of applications in various sciences, from medicine to flow mechanics. In this report, we survey a state-of-the-art on time-varying volume rendering. We state several basic concepts and then we establish several criteria to classify the studied works: IVR versus DVR, 4D versus 3D+time, compression techniques, involved architectures, use of parallelism and image-space versus objectspace coherence. We also address other related problems as transfer functions and 2D cross-sections computation of time-varying volume data. All the papers reviewed are classified into several tables based on the mentioned classification and, finally, several conclusions are presented.
Abstract: Skeletons are compact shape descriptions of discrete images. They have been extensively... more Abstract: Skeletons are compact shape descriptions of discrete images. They have been extensively studied because of their utility in various applications such as data compression, shape abstraction, navigation and features detection. In this article, a new Euclidean skeletal definition for 2D discrete objects based on the Distance Map (DMAT) is being proposed. As a novel feature, it is shown that this skeleton is a connected subset of the discretization of the continuous medial axis of the object....
Proc. 7th International Fall Workshop Vision, …, 2002
This paper addresses the rendering of aligned regular multimodal datasets. It presents a general ... more This paper addresses the rendering of aligned regular multimodal datasets. It presents a general framework of multimodal data fusion that includes several data merging methods. We also analyze the requirements of a rendering system able to provide these different fusion methods. On the basis of these requirements, we propose a novel design for a multimodal rendering system. The design has been implemented and proved showing to be efficient and flexible.
Conferencia de la Asociacion Espanola para la Inteligencia Artificial, 2005
Abstract. This paper analyzes how to introduce machine learning algorithms into the process of di... more Abstract. This paper analyzes how to introduce machine learning algorithms into the process of direct volume rendering. A conceptual framework for the optical property function elicitation process is proposed and particularized for the use of attribute-value classifiers. The process is evaluated in terms of accuracy and speed using four different off-theshelf classifiers (J48, Nave Bayes, Simple Logistic and ECOC-Adaboost). The empirical results confirm the classification of biomedical datasets as a tough problem where an opportunity ...
The manufacturing domain is regarded as one of the most important engineering areas. Recently, sm... more The manufacturing domain is regarded as one of the most important engineering areas. Recently, smart manufacturing merges the use of sensors, intelligent controls, and software to manage each stage in the manufacturing lifecycle. Additionally, the increasing use of point clouds to model real products and machining tools in a virtual space facilitates the more accurate monitoring of the end-to-end production lifecycle. Thus, the conjunction of both, intelligent methods and more accurate 3D models allows the prediction of uncertainties and anomalies in the manufacturing process as well as reduces the final production costs. However, the high complexity of the geometrical structures defined by point clouds and the high accuracy required by the Quality Assurance/Quality control parameters during the process, pave the way for continuous improvements in smart manufacturing methods. This paper addresses a comprehensive analysis of machining tool identification utilizing temporal point clou...
Volume rendering is a very active research field in Computer Graphics because of its wide range o... more Volume rendering is a very active research field in Computer Graphics because of its wide range of applications in various sciences, from medicine to flow mechanics. In this report, we survey a state-of-the-art on time-varying volume rendering. We state several basic concepts and then we establish several criteria to classify the studied works: IVR versus DVR, 4D versus 3D+time, compression techniques, involved architectures, use of parallelism and image-space versus objectspace coherence. We also address other related problems as transfer functions and 2D cross-sections computation of time-varying volume data. All the papers reviewed are classified into several tables based on the mentioned classification and, finally, several conclusions are presented.
International Conference in Central Europe on Computer Graphics and Visualization, 2004
Hybrid rendering of volume and polygonal model is an interesting feature of visualization systems... more Hybrid rendering of volume and polygonal model is an interesting feature of visualization systems, since it helps users to better understand the relationships between internal structures of the volume and fitted surfaces as well as external surfaces. Most of the existing bibliography focuses at the problem of correctly integrating in depth both types of information. The rendering method proposed in
International Conference on Pattern Recognition, 2000
The 3D reconstruction of the cerebral vascular anatomy can greatly improve the diagnosis of vascu... more The 3D reconstruction of the cerebral vascular anatomy can greatly improve the diagnosis of vascular pathologies, such as embolisms and haemorrhages. This paper presents a new method for the automatic extraction of the blood vessels surface and the labelling of its features, specifically branching, aneurysms and stenoses. The method works with segmented magnetic resonance angiography images. It extracts a discrete
Abstract. This paper analyzes how to introduce machine learning algorithms into the process of di... more Abstract. This paper analyzes how to introduce machine learning algorithms into the process of direct volume rendering. A conceptual framework for the optical property function elicitation process is proposed and particularized for the use of attribute-value classifiers. The process is evaluated in terms of accuracy and speed using four different off-theshelf classifiers (J48, Naıve Bayes, Simple Logistic and ECOC-Adaboost). The empirical results confirm the classification of biomedical datasets as a tough problem where an opportunity ...
An interactive cerebral blood vessel exploration system is described. It has been designed on the... more An interactive cerebral blood vessel exploration system is described. It has been designed on the basis of neurosurgeon's requirements in order t,o assist them in the diagnosis of vascular pathologies. The system is based on the construction of a symbolic model of the vascular tree with an automatic identification and labelling of vessel bifurcations, aneurysms and stenoses. It provides several types of visualization: individual MRA slices, MIP, shaded rendermg, symbolic scheme and surface reconstruction.
This paper describes a 3D tool machining simulation system. The initial tool and the grinding whe... more This paper describes a 3D tool machining simulation system. The initial tool and the grinding wheels are integrated with the machine tool. The application reads and interprets the CNC program code that controls the machine, it computes the positions and the motion of ...
... processing. Most of the modeling and visualization systems referenced in the bibliography (Vo... more ... processing. Most of the modeling and visualization systems referenced in the bibliography (VolVis [29], 3D Viewnix [30], BOB [31]) use a quick simplified default visualization for the interaction. ... 31. ChinPurcell, K., BOB: brick of bytes. ...
Direct cell-to-cell volume visualization algorithms, also called projective rendering methods, pr... more Direct cell-to-cell volume visualization algorithms, also called projective rendering methods, present the advantage of allowing semi-transparencies and, additionally, as they project all the samples, they avoid the voxel-space aliasing. However, they are generally computationally expensive and artifacts may appear in the projection. In this paper, different projective strategies are reviewed and compared. A new algorithm, based on a back-to-front (BTF)
This paper addresses the simulation of drilling tools CNC machining. It describes a novel approac... more This paper addresses the simulation of drilling tools CNC machining. It describes a novel approach for the computation of the boundary representation of the machined tools. Machining consists of a sequence of boolean operations of difference between the tool and the grinding wheels through time. The proposed method performs the dynamic boolean operations on cross sections of the tool and it reconstructs the 3Dmodel by tiling between the cross sections. The method is based on classical computational geometry algorithms such as intersection tests, hull computations, 2D boolean operations and surface tiling. This approach is efficient and it provides user control on the resolution of the operations.
This paper introduces a machine learning approach into the process of direct volume rendering of ... more This paper introduces a machine learning approach into the process of direct volume rendering of biomedical highresolution 3D images. More concretely, it proposes a learning pipeline process that generates the classification function within the optical property function used for rendering. Briefly, this pipeline starts with a data acquisition and selection task, it is followed by a feature extraction process, to be ended with sequence of supervised learning steps. Learning comprises Gentle Boost and CRF (Conditional Random Fields) ...
The goal of this paper is the proposal and evaluation of a ray-casting strategy that takes advant... more The goal of this paper is the proposal and evaluation of a ray-casting strategy that takes advantage of the spatial and temporal coherence in image-space as well as in object-space in order to speed up rendering. It is based on a double structure: in image-space, a temporal buffer that stores for each pixel the next instant of time in which the pixel must be recomputed, and in object-space a Temporal Run-Length Encoding of the voxel values through time. The algorithm skips empty and unchanged pixels through three different spaceleaping strategies. It can compute the images sequentially in time or generate them simultaneously in batch. In addition, it can handle simultaneously several data modalities. Finally, an on-purpose out-of-core strategy is used to handle large datasets. The tests performed on two medical datasets and various phantom datasets show that the proposed strategy significantly speeds-up rendering.
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Papers by Ana Puig