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Variable Rate Deep Image Compression with Modulated Autoencoder [article]

Fei Yang, Luis Herranz, Joost van de Weijer, José A. Iglesias Guitián, Antonio López, Mikhail Mozerov
2019 arXiv   pre-print
Iglesias Guitin, A. Lpez and M. Mozerov are with the Computer Vision Center of Department Informatics, Universitat Autnoma de Barcelona, Barcelona, Spain, 08193.  ... 
arXiv:1912.05526v1 fatcat:4bxstnwrnnerpp4efatssyzpoa

Context Preserving Focal Probes for Exploration of Volumetric Medical Datasets [chapter]

Yanlin Luo, José Antonio Iglesias Guitián, Enrico Gobbetti, Fabio Marton
2009 Lecture Notes in Computer Science  
During real-time medical data exploration using volume rendering, it is often difficult to enhance a particular region of interest without losing context information. In this paper, we present a new illustrative technique for focusing on a user-driven region of interest while preserving context information. Our focal probes define a region of interest using a distance function which controls the opacity of the voxels within the probe, exploit silhouette enhancement and use non-photorealistic shading techniques to improve shape depiction.
doi:10.1007/978-3-642-10470-1_16 fatcat:rx6rpyqwtzakrlgh4nekfsxctu

Towards Advanced Volumetric Display of the Human Musculoskeletal System [article]

Marco Agus, Andrea Giachetti, Enrico Gobbetti, José Antonio Iglesias Guitián, Fabio Marton
2008 Smart Tools and Applications in Graphics  
We report on our research results on effective volume visualization techniques for medical and anatomical data. Our volume rendering approach employs GPU accelerated out-of-core direct rendering algorithms to fully support high resolution, 16 bits, raw medical datasets as well as segmentation. Images can be presented on a special light field display based on projection technology. Human anatomical data appear to moving viewers floating in the light field display space and can be interactively manipulated.
doi:10.2312/localchapterevents/italchap/italianchapconf2008/021-025 dblp:conf/egItaly/AgusGGGM08 fatcat:n5lpaciyhfci5gixwvlln322lm

View-dependent exploration of massive volumetric models on large-scale light field displays

José Antonio Iglesias Guitián, Enrico Gobbetti, Fabio Marton
2010 The Visual Computer  
José Antonio Iglesias Guitián is a Marie Curie Early Stage Researcher in the Visual Computing group of the Center for Advanced Studies, Research and Development in Sardinia (CRS4).  ... 
doi:10.1007/s00371-010-0453-y fatcat:3byuukhlhvdufcqki3rlj5wfhu

Split-Voxel: A Simple Discontinuity-Preserving Voxel Representation for Volume Rendering [article]

Marco Agus, Enrico Gobbetti, José Antonio Iglesias Guitián, Fabio Marton
2010 International Workshop on Volume Graphics, Proceedings of the  
Finally, the split-voxel model is incorporated into a multiresolution CUDA rendering framework, whose data structures and rendering strategy are similar to those described by Iglesias Guitián et al.  ... 
doi:10.2312/vg/vg10/021-028 fatcat:zuln62rewnfqxnynu6f6gyhgia

GPU Accelerated Direct Volume Rendering on an Interactive Light Field Display

Marco Agus, Enrico Gobbetti, José Antonio Iglesias Guitiàn, Fabio Marton, Giovanni Pintore
2008 Computer graphics forum (Print)  
We present a GPU accelerated volume ray casting system interactively driving a multi-user light field display. The display, driven by a single programmable GPU, is based on a specially arranged array of projectors and a holographic screen and provides full horizontal parallax. The characteristics of the display are exploited to develop a specialized volume rendering technique able to provide multiple freely moving naked-eye viewers the illusion of seeing and manipulating virtual volumetric
more » ... ts floating in the display workspace. In our approach, a GPU ray-caster follows rays generated by a multiple-center-of-projection technique while sampling pre-filtered versions of the dataset at resolutions that match the varying spatial accuracy of the display. The method achieves interactive performance and provides rapid visual understanding of complex volumetric data sets even when using depth oblivious compositing techniques.
doi:10.1111/j.1467-8659.2008.01120.x fatcat:u2kwqbfn2vhuznfrnptv4m4zju

An interactive 3D medical visualization system based on a light field display

Marco Agus, Fabio Bettio, Andrea Giachetti, Enrico Gobbetti, José Antonio Iglesias Guitián, Fabio Marton, Jonas Nilsson, Giovanni Pintore
2009 The Visual Computer  
We present a prototype medical data visualization system exploiting a light field display and custom direct volume rendering techniques to enhance understanding of massive volumetric data, such as CT, MRI, and PET scans. The system can be integrated with standard medical image archives and extends the capabilities of current radiology workstations by supporting real-time rendering of volumes of potentially unlimited size on light field displays generating dynamic observer-independent light
more » ... s. The system allows multiple untracked naked-eye users in a sufficiently large interaction area to coherently perceive rendered volumes as real objects, with stereo and motion parallax cues. In this way, an effective collaborative analysis of volumetric data can be achieved. Evaluation tests demonstrate the usefulness of the generated depth cues and the improved performance in understanding complex spatial structures with respect to standard techniques.
doi:10.1007/s00371-009-0311-y fatcat:qnfod6t35va2taxc35ioqnnn2q

A single-pass GPU ray casting framework for interactive out-of-core rendering of massive volumetric datasets

Enrico Gobbetti, Fabio Marton, José Antonio Iglesias Guitián
2008 The Visual Computer  
We present an adaptive out-of-core technique for rendering massive scalar volumes employing single pass GPU raycasting. The method is based on the decomposition of a volumetric dataset into small cubical bricks, which are then organized into an octree structure maintained out-of-core. The octree contains the original data at the leaves, and a filtered representation of children at inner nodes. At runtime an adaptive loader, executing on the CPU, updates a viewand transfer function-dependent
more » ... ing set of bricks maintained on GPU memory by asynchronously fetching data from the out-of-core octree representation. At each frame, a compact indexing structure, which spatially organizes the current working set into an octree hierarchy, is encoded in a small texture. This data structure is then exploited by an efficient stackless raycasting algorithm, which computes the volume rendering integral by visiting non-empty bricks in front-to-back order and adapting sampling density to brick resolution. Block visibility information is fed back to the loader to avoid refinement and data loading of occluded zones. The resulting method is able to interactively explore multigiga-voxel datasets on a desktop PC.
doi:10.1007/s00371-008-0261-9 fatcat:nne6u463tvggzjirl2ou4qm5xu

COVRA: A compression-domain output-sensitive volume rendering architecture based on a sparse representation of voxel blocks

Enrico Gobbetti, José Antonio Iglesias Guitián, Fabio Marton
2012 Computer graphics forum (Print)  
We present a novel multiresolution compression-domain GPU volume rendering architecture designed for interactive local and networked exploration of rectilinear scalar volumes on commodity platforms. In our approach, the volume is decomposed into a multiresolution hierarchy of bricks. Each brick is further subdivided into smaller blocks, which are compactly described by sparse linear combinations of prototype blocks stored in an overcomplete dictionary. The dictionary is learned, using limited
more » ... mputational and memory resources, by applying the K-SVD algorithm to a re-weighted non-uniformly sampled subset of the input volume, harnessing the recently introduced method of coresets. The result is a scalable high quality coding scheme, which allows very large volumes to be compressed off-line and then decompressed on-demand during real-time GPU-accelerated rendering. Volumetric information can be maintained in compressed format through all the rendering pipeline. In order to efficiently support high quality filtering and shading, a specialized real-time renderer closely coordinates decompression with rendering, combining at each frame images produced by raycasting selectively decompressed portions of the current view-and transfer-function-dependent working set. The quality and performance of our approach is demonstrated on massive static and time-varying datasets.
doi:10.1111/j.1467-8659.2012.03124.x fatcat:c4klzynmyncvfczc7bkebv3gfe

Using Machine Learning Techniques to Predict MACE in Very Young Acute Coronary Syndrome Patients

Pablo Juan-Salvadores, Cesar Veiga, Víctor Alfonso Jiménez Díaz, Alba Guitián González, Cristina Iglesia Carreño, Cristina Martínez Reglero, José Antonio Baz Alonso, Francisco Caamaño Isorna, Andrés Iñiguez Romo
2022 Diagnostics  
Coronary artery disease is a chronic disease with an increased expression in the elderly. However, different studies have shown an increased incidence in young subjects over the last decades. The prediction of major adverse cardiac events (MACE) in very young patients has a significant impact on medical decision-making following coronary angiography and the selection of treatment. Different approaches have been developed to identify patients at a higher risk of adverse outcomes after their
more » ... ary anatomy is known. This is a prognostic study of combined data from patients ≤40 years old undergoing coronary angiography (n = 492). We evaluated whether different machine learning (ML) approaches could predict MACE more effectively than traditional statistical methods using logistic regression (LR). Our most effective model for long-term follow-up (60 ± 27 months) was random forest (RF), obtaining an area under the curve (AUC) = 0.79 (95%CI 0.69–0.88), in contrast with LR, obtaining AUC = 0.66 (95%CI 0.53–0.78, p = 0.021). At 1-year follow-up, the RF test found AUC 0.80 (95%CI 0.71–0.89) vs. LR 0.50 (95%CI 0.33–0.66, p < 0.001). The results of our study support the hypothesis that ML methods can improve both the identification of MACE risk patients and the prediction vs. traditional statistical techniques even in a small sample size. The application of ML techniques to focus the efforts on the detection of MACE in very young patients after coronary angiography could help tailor upfront follow-up strategies in such young patients according to their risk of MACE and to be used for proper assignment of health resources.
doi:10.3390/diagnostics12020422 pmid:35204511 pmcid:PMC8870965 fatcat:k3u3xff43vasnbuhefamqfjws4

A real-time coarse-to-fine multiview capture system for all-in-focus rendering on a light-field display

Fabio Marton, Enrico Gobbetti, Fabio Bettio, Jose Antonio Iglesias Guitian, Ruggero Pintus
2011 2011 3DTV Conference: The True Vision - Capture, Transmission and Display of 3D Video (3DTV-CON)  
We present an end-to-end system capable of real-time capturing and displaying with full horizontal parallax high-quality 3D video contents on a cluster-driven multiprojector light-field display. The capture component is an array of low-cost USB cameras connected to a single PC. Raw M-JPEG data coming from the software-synchronized cameras are multicast over Gigabit Ethernet to the back-end nodes of the rendering cluster, where they are decompressed and rendered. For all-in-focus rendering,
more » ... dependent depth is estimated on the GPU using a customized multiview space-sweeping approach based on fast Census-based area matching implemented in CUDA. Realtime performance is demonstrated on a system with 18 VGA cameras and 72 SVGA rendering projectors. Index Terms-Multi-view capture and display, GPU, light field rendering
doi:10.1109/3dtv.2011.5877176 fatcat:puvqqueek5hmvd7tft7ugpe5qq

Kpi, a chaperone-usher pili system associated with the worldwide-disseminated high-risk clone Klebsiella pneumoniae ST-15

Eva Gato, Juan Carlos Vázquez-Ucha, Soraya Rumbo-Feal, Laura Álvarez-Fraga, Juan A. Vallejo, Marta Martínez-Guitián, Alejandro Beceiro, Jose Ramos Vivas, Pedro J. Sola Campoy, María Pérez-Vázquez, Jesus Oteo Iglesias, Bruno Kotska Rodiño-Janeiro (+4 others)
2020 Proceedings of the National Academy of Sciences of the United States of America  
Control of infections caused by carbapenem-resistant Klebsiella pneumoniae continues to be challenging. The success of this pathogen is favored by its ability to acquire antimicrobial resistance and to spread and persist in both the environment and in humans. The emergence of clinically important clones, such as sequence types 11, 15, 101, and 258, has been reported worldwide. However, the mechanisms promoting the dissemination of such high-risk clones are unknown. Unraveling the factors that
more » ... ay a role in the pathobiology and epidemicity of K. pneumoniae is therefore important for managing infections. To address this issue, we studied a carbapenem-resistant ST-15 K. pneumoniae isolate (Kp3380) that displayed a remarkable adherent phenotype with abundant pilus-like structures. Genome sequencing enabled us to identify a chaperone-usher pili system (Kpi) in Kp3380. Analysis of a large K. pneumoniae population from 32 European countries showed that the Kpi system is associated with the ST-15 clone. Phylogenetic analysis of the operon revealed that Kpi belongs to the little-characterized γ2-fimbrial clade. We demonstrate that Kpi contributes positively to the ability of K. pneumoniae to form biofilms and adhere to different host tissues. Moreover, the in vivo intestinal colonizing capacity of the Kpi-defective mutant was significantly reduced, as was its ability to infect Galleria mellonella. The findings provide information about the pathobiology and epidemicity of Kpi+K. pneumoniae and indicate that the presence of Kpi may explain the success of the ST-15 clone. Disrupting bacterial adherence to the intestinal surface could potentially target gastrointestinal colonization.
doi:10.1073/pnas.1921393117 pmid:32641516 fatcat:wsm7u5rysrb3lbdej7fmdkca4q

El convento de San Martiño de Vilalourente en Mondoñedo. La transformación moderna de un cenobio medieval

Javier Gómez Darriba
2020 BSAA Arte  
José Martínez Celiz. 1715-1716. Mondoñedo. Fotografía del autor 37 AHPLu, P.N., leg. 6856-3, ff. 10-11 y 173; Lence-Santar y Guitián (1912): 18.  ...  A finales de dicha centuria lograron construir un nuevo claustro, y en el primer cuarto de la siguiente el asturiano José Martínez Celiz diseñó una nueva iglesia.  ... 
doi:10.24197/bsaaa.86.2020.253-280 fatcat:o2psyoevsve4tnhed2jqcfiqoy

El convento de la Concepción de Mondoñedo: arquitectura y mobiliario de una clausura dieciochesca

Javier Gómez Darriba
2021 Cuadernos de Arte de la Universidad de Granada  
En el presente trabajo analizaremos la disputa habida en la Iglesia local por causa de su refundación; aportaremos la identidad del arquitecto que trazó la obra y de los aparejadores que la edificaron;  ...  La escritura también cita las esculturas de san Pedro, san José, san Francisco de Asís, san Bernardo y san Antonio de Padua, aunque esta última también se sustituyó por un san Bernardino de Siena.  ...  José Martínez Celiz. Portada del convento de la Concepción (1713-1717). Mondoñedo, España. Fotografía del autor. Fig. 4 . 4 Fig. 4. José Martínez Celiz.  ... 
doi:10.30827/caug.v52i0.22905 fatcat:fvicsfb4kbc25c3mpfbowiunr4

El arquitecto José Martínez Celiz y la introducción del barroco asturiano en Galicia

Javier Gómez Darriba
2021 Liño  
La excepción a esta regla la supuso José Martínez Celiz, un arquitecto de origen avilesino que introdujo en Galicia un repertorio de formas y modelos inéditos en la región, pero sobradamente trabajados  ...  Fig. 4 . 4 José Martínez Celiz, interior de la iglesia conventual de San Martiño de Vilalourente en Mondoñedo, 1715-1716, fotografía del autor. Fig. 5 . 5 ¿José Martínez Celiz?  ...  José Martínez Celiz, portada de la iglesia conventual de la Encarnación en Mondoñedo, 1713-1717, fotografía del autor. 30 31 Fig. 3.  ... 
doi:10.17811/li.27.2021.45-56 fatcat:cmecg7aqabbulci5a3qzhu4y6m
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