CEIG18

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https://diglib.eg.org/handle/10.2312/2632545

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Browsing CEIG18 by Subject "Computer graphics"

Now showing 1 - 5 of 5
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    Depth Map Repairing for Building Reconstruction
    (The Eurographics Association, 2018) Andújar, Carlos; Argudo, Oscar; Besora, Isaac; Brunet, Pere; Chica, Antoni; Comino Trinidad, Marc; García-Fernández, Ignacio and Ureña, Carlos
    Structure-from-motion along with multi-view stereo techniques jointly allow for the inexpensive scanning of 3D objects (e.g. buildings) using just a collection of images taken from commodity cameras. Despite major advances in these fields, a major limitation of dense reconstruction algorithms is that correct depth/normal values are not recovered on specular surfaces (e.g. windows) and parts lacking image features (e.g. flat, textureless parts of the facade). Since these reflective properties are inherent to the surface being acquired, images from different viewpoints hardly contribute to solve this problem. In this paper we present a simple method for detecting, classifying and filling non-valid data regions in depth maps produced by dense stereo algorithms. Triangles meshes reconstructed from our repaired depth maps exhibit much higher quality than those produced by state-of-the-art reconstruction algorithms like Screened Poisson-based techniques.
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    Muscle Simulation with Extended Position Based Dynamics
    (The Eurographics Association, 2018) Romeo, Marco; Monteagudo, Carlos; Sánchez-Quirós, Daniel; García-Fernández, Ignacio and Ureña, Carlos
    Recent research on muscle simulation for Visual Effects relies on numerical methods such as the Finite Element Method or Finite Volume Method. These approaches produce realistic results, but require high computational time and are complex to set up. On the other hand Position Based Dynamics offers a fast and controllable solution to simulate surfaces and volumes, but there is no literature on how to implement constraints that could be used to realistically simulate muscles for digital creatures with this method. In this paper we extend the current state-of-the-art in Position Based Dynamics to efficiently compute realistic skeletal-muscle simulation. In particular we embed muscle fibers in the solver by adding an anisotropic component to the distance constraints between mesh points and apply overpressure to realistically model muscle volume changes under contraction. We also present a technique that consistently provides an internal structure for our muscle volumes. We use this structure to preserve the shape and extract relevant information for the activation of the muscle fibers. Finally, we propose a modification of the Extended Position Based Dynamics algorithm and describe other details for proper simulation of character’'s muscle dynamics.
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    Noise Reduction Automation of LiDAR Point Clouds for Modeling and Representation of High Voltage Lines in a 3D Virtual Globe
    (The Eurographics Association, 2018) Santana, Jaisiel; Ortega, Sebastián; Santana, José Miguel; Trujillo, Agustin; Suárez, Jose Pablo; García-Fernández, Ignacio and Ureña, Carlos
    Due to the importance of electricity supply, electric companies must inspect their infrastructure in order to guarantee the reliability of the service. In this scenario, many companies use LiDAR technology for modeling the power line corridors and detect possible anomalies and risks. This process is quite expensive in terms of costs and human dependency so, maximizing the automation of the process is critical. In this paper, a method for reducing turbulence-noise in airborne LiDAR point clouds for a posterior visualization of a power line corridor in a virtual 3D-globe is presented. Based on an analysis performed against a set of point clouds that indicates that most noise is composed of a mass which follows the helicopter trajectory, the method attempts to integrate a noise reduction process using the distance between points and the helicopter as cleaning criterion. A comparison between a proposed variation of a classification method using a point cloud manually filtered and the same method variation but integrating the presented noise reduction method is carried out to validate the automation effectiveness. Finally, the resulting model is displayed using a virtual 3D-globe, easing analytical tasks.
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    Rendering and Interacting With Volume Models in Immersive Environments
    (The Eurographics Association, 2018) Fons, Joan; Monclús, Eva; Vázquez, Pere-Pau; Navazo, Isabel; García-Fernández, Ignacio and Ureña, Carlos
    The recent advances in VR headsets, such as the Oculus Rift or HTC Vive, at affordable prices offering a high resolution display, has empowered the development of immersive VR applications. data. In this paper we propose an immersive VR system that uses some well-known acceleration algorithms to achieve real-time rendering of volumetric datasets in an immersive VR system. Moreover, we have incorporated different basic interaction techniques to facilitate the inspection of the volume dataset. The interaction has been designed to be as natural as possible in order to achieve the most comfortable, user-friendly virtual experience. We have conducted an informal user study to evaluate the user preferences. Our evaluation shows that our application is perceived usable, easy of learn and very effective in terms of the high level of immersion achieved.
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    Study of the Influence of User Characteristics on the Virtual Reality Presence
    (The Eurographics Association, 2018) Mayor, Jesús; Sánchez, Alberto; Raya, Laura; García-Fernández, Ignacio and Ureña, Carlos
    In recent years, virtual reality has grown a lot in different areas of application, including ludic, social and research, being used by a large and growing number of users with different profiles. Presence is one of the most distinctive and important features of a virtual reality experience. The aim of this article is to study the most suitable areas of application for users and to analyze the influence of different characteristics of the user's profile in the perceived presence. We have tested the interest applications indicated by 159 subjects and we have designed an immersive virtual reality experience, testing the behavior and performance of 48 users. The results obtained show that gender can influence the perceptual sensation of presence in these types of virtual environments.