2016 23° Encontro Português de Computação Gráfica e Interação (EPCGI)最新文献

GParticles: A flexible GPU-based particle library GParticles:灵活的基于gpu的粒子库

2016 23° Encontro Português de Computação Gráfica e Interação (EPCGI) Pub Date : 2016-11-24 DOI: 10.1109/EPCGI.2016.7851183

Tiago Dinis, A. Fernandes

引用次数: 0

Non-homogeneous grids for CPU-GPU ray tracing 用于CPU-GPU光线跟踪的非均匀网格

2016 23° Encontro Português de Computação Gráfica e Interação (EPCGI) Pub Date : 2016-11-01 DOI: 10.1109/EPCGI.2016.7851186

Vasco S. Costa, J. Pereira, J. Jorge

{"title":"Non-homogeneous grids for CPU-GPU ray tracing","authors":"Vasco S. Costa, J. Pereira, J. Jorge","doi":"10.1109/EPCGI.2016.7851186","DOIUrl":"https://doi.org/10.1109/EPCGI.2016.7851186","url":null,"abstract":"Ray tracing is among the most resource consuming methods for realistic image generation. Over the years, different acceleration structures have been proposed to reduce ray-object intersection queries since these dominate execution time. Regular grids are one of the most popular structures due to their simplicity and effectiveness. However, regular grid implementations are plagued by two major issues: underwhelming performance on irregular scenes with unbalanced triangle density and high memory consumption due to the many empty cells in sparsely populated scenes, typical of many game scenarios. We present a novel hybrid solution based on non-homogeneous rectilinear grids to improve ray tracing performance on uneven scene distributions. Additionally, we use hashing to get rid of empty cells. Non-homogeneous grids feature moveable split planes along the three axes unlike regular grids where split planes must be equidistant. Our approach performs serial construction tasks such as compression in the CPU and offloads the remaining data parallel tasks to the GPU. Using this acceleration structure we are able to render a wide range of scenes at high frame rates on commodity graphics hardware, from irregular density low polygon count models to regular density high polygon count scanned scenes with rapid construction times and a small memory footprint. For some test cases, our approach nearly doubles the frame rate of a regular grid at a similar resolution, while featuring low build times.","PeriodicalId":307741,"journal":{"name":"2016 23° Encontro Português de Computação Gráfica e Interação (EPCGI)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122558628","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

A visualisation and simulation framework for local and remote HRI experimentation 本地和远程HRI实验的可视化和仿真框架

2016 23° Encontro Português de Computação Gráfica e Interação (EPCGI) Pub Date : 2016-11-01 DOI: 10.1109/EPCGI.2016.7851191

A. Gradil, J. Ferreira

{"title":"A visualisation and simulation framework for local and remote HRI experimentation","authors":"A. Gradil, J. Ferreira","doi":"10.1109/EPCGI.2016.7851191","DOIUrl":"https://doi.org/10.1109/EPCGI.2016.7851191","url":null,"abstract":"In this text, we will present work on the design and development of a ROS-based (Robot Operating System1) remote 3D visualisation, control and simulation framework. This architecture has the purpose of extending the usability of a system devised in previous work by this research team during the CASIR (Coordinated Attention for Social Interaction with Robots) project. The proposed solution was implemented using ROS, and designed to attend the needs of two user groups — local and remote users and developers. The framework consists of: (1) a fully functional simulator integrated with the ROS environment, including a faithful representation of a robotic platform, a human model with animation capabilities and enough features for enacting human robot interaction scenarios, and a virtual experimental setup with similar features as the real laboratory workspace; (2) a fully functional and intuitive user interface for monitoring and development; (3) a remote robotic laboratory that can connect remote users to the framework via a web browser. The proposed solution was thoroughly and systematically tested under operational conditions, so as to assess its qualities in terms of features, ease-of-use and performance. Finally, conclusions concerning the success and potential of this research and development effort are drawn, and the foundations for future work will be proposed.","PeriodicalId":307741,"journal":{"name":"2016 23° Encontro Português de Computação Gráfica e Interação (EPCGI)","volume":"178 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122859148","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Presence in virtual environments: Objective metrics vs. subjective metrics — A pilot study 虚拟环境中的存在:客观度量vs.主观度量——初步研究

2016 23° Encontro Português de Computação Gráfica e Interação (EPCGI) Pub Date : 2016-11-01 DOI: 10.1109/EPCGI.2016.7851200

Miguel Melo, Tânia Rocha, Luís Barbosa, M. Bessa

{"title":"Presence in virtual environments: Objective metrics vs. subjective metrics — A pilot study","authors":"Miguel Melo, Tânia Rocha, Luís Barbosa, M. Bessa","doi":"10.1109/EPCGI.2016.7851200","DOIUrl":"https://doi.org/10.1109/EPCGI.2016.7851200","url":null,"abstract":"The sense of presence and cybersickness are key-factors to have into account when referring to Virtual Environments (VE). To achieve high levels of presence and minimize cybersickness, it is important to ensure that the user's stimulation is coherent with the contents that are being delivered. In this paper, it is presented a pilot study addressing the usage of both objective and subjective metrics to measure the sense of presence and cybersickness in VE in order to study possible correlations between these two evaluation approaches. On top of that, the pilot study includes two body positions to allow evaluating if the stimulation of the vestibular study has impact on the sense of presence and cybersickness. To evaluate presence and cybersickness, it was developed a VE that consists in a hill where participants ride a bicycle. To broaden the scope of the study, there were studied two body positions: standing and sitting on the bicycle. The equipment EMOTIV epoc+ was used to register the objective metrics. The subjective metrics were registered using the Igroup Presence Questionnaire (IPQ) and the Simulator Sickness Questionnaire (SSQ). To complement the collected data, the levels of fatigue and stress before and after the experience were also registered through self-evaluation. Results show that objective metrics Interest and Stress and the subjective metrics Realism, Fatigue and Stress have a positive interaction regarding the sense of presence. Results further suggest that there is a positive interaction between the objective metric Focus and the subjective metric Involvement.","PeriodicalId":307741,"journal":{"name":"2016 23° Encontro Português de Computação Gráfica e Interação (EPCGI)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122212197","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Pointer dynamics as cognitive biometrics 指针动态作为认知生物计量学

2016 23° Encontro Português de Computação Gráfica e Interação (EPCGI) Pub Date : 2016-11-01 DOI: 10.1109/EPCGI.2016.7851203

Liliana Cunha, S.T. de Magalhaes, Vítor J. Sá, H. Santos

{"title":"Pointer dynamics as cognitive biometrics","authors":"Liliana Cunha, S.T. de Magalhaes, Vítor J. Sá, H. Santos","doi":"10.1109/EPCGI.2016.7851203","DOIUrl":"https://doi.org/10.1109/EPCGI.2016.7851203","url":null,"abstract":"Biometric authentication technologies aim to increase the precision of security systems and have given proof of their effectiveness. Cognitive biometrics, in particular, has shown the potential of raising security levels, although lacking somewhat in terms of precision and adequate research. Therefore, this study analyses the viability of the usage of the Pointer Dynamics biometric technique as cognitive biometrics, under certain conditions. To this end, an algorithm was developed, whose identity validation criterion is the execution of the individual pattern in the manner of interaction with the mouse, when selecting the grids of the graphic secret. Authentication and fraudulent authentication tests were conducted with two types of images, one with a supposed emotional meaning for the user, and one without. This was done so as to allow the comparison of results brought forth by the application of the technique with and without cognitive stimulus. Although results do not allow definite conclusions to be drawn, the fact is that the False Acceptance Rate of both the cognitive tests and graphs present marked relative variations, for thresholds between 4 and 7, which indicate that it is likely that the cognitive stimulus has increased the resistance to attempts of fraudulent authentication.","PeriodicalId":307741,"journal":{"name":"2016 23° Encontro Português de Computação Gráfica e Interação (EPCGI)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121209534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Augmented reality for support decision on solar radiation harnessing 增强现实技术支持太阳辐射利用决策

2016 23° Encontro Português de Computação Gráfica e Interação (EPCGI) Pub Date : 2016-11-01 DOI: 10.1109/EPCGI.2016.7851201

M. B. Carmo, A. Cláudio, António Ferreira, A. Afonso, P. Redweik, C. Catita, Miguel Centeno Brito, Silvana Silva, Carolina Meireles

{"title":"Augmented reality for support decision on solar radiation harnessing","authors":"M. B. Carmo, A. Cláudio, António Ferreira, A. Afonso, P. Redweik, C. Catita, Miguel Centeno Brito, Silvana Silva, Carolina Meireles","doi":"10.1109/EPCGI.2016.7851201","DOIUrl":"https://doi.org/10.1109/EPCGI.2016.7851201","url":null,"abstract":"The use of mobile devices, such as smartphones and tablets, is widespread nowadays because they are portable, affordable, and offer a diversity of features. This type of equipment supports Augmented Reality (AR) applications, since they have all the necessary characteristics: good processing power, are equipped with cameras, sensors, such as accelerometers, magnetometers and gyroscopes, provide geo-location system and Web-connectivity. Having AR applications in this type of devices makes them available to a large audience. In particular, mobile AR applications can help disseminating the use of renewable energy, providing mechanisms to calculate the potential gains of its use. These applications can also be a valuable tool for technicians and researchers in this field. In the case of solar energy, the installation of photovoltaic modules is no longer limited to roofs, because there is specific equipment to install in walls or windows, surfaces that are suitable for presenting information in AR. Extending previous work on data visualization of solar radiation in RA, this article presents an application to simulate the installation of a photovoltaic module on the walls of a building. The user can control the module position on the wall by dragging its icon on the screen. When the module position is chosen, the application provides information about the amount of produced energy which, obviously, depends on the module position on the wall. A user study conducted with volunteers revealed a positive overall assessment of the application.","PeriodicalId":307741,"journal":{"name":"2016 23° Encontro Português de Computação Gráfica e Interação (EPCGI)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129374857","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Separating degrees of freedom for object manipulation in VR 在VR中分离物体操作的自由度

2016 23° Encontro Português de Computação Gráfica e Interação (EPCGI) Pub Date : 2016-11-01 DOI: 10.1109/EPCGI.2016.7851188

Filipe Relvas, Daniel Mendes, Alfredo Ferreira, Joaquim Jorge

引用次数: 1

Healed marching cubes algorithm for non-manifold implicit surfaces 非流形隐式曲面的愈合行军立方体算法

2016 23° Encontro Português de Computação Gráfica e Interação (EPCGI) Pub Date : 2016-11-01 DOI: 10.1109/EPCGI.2016.7851184

Q. T. Nguyen, A. Gomes

引用次数: 1

The impact of different exposure times to 360° video experience on the sense of presence 不同曝光时间对360°视频体验对临场感的影响

2016 23° Encontro Português de Computação Gráfica e Interação (EPCGI) Pub Date : 2016-11-01 DOI: 10.1109/EPCGI.2016.7851192

Miguel Melo, Sofia Sampaio, Luís Barbosa, J. Vasconcelos-Raposo, M. Bessa

{"title":"The impact of different exposure times to 360° video experience on the sense of presence","authors":"Miguel Melo, Sofia Sampaio, Luís Barbosa, J. Vasconcelos-Raposo, M. Bessa","doi":"10.1109/EPCGI.2016.7851192","DOIUrl":"https://doi.org/10.1109/EPCGI.2016.7851192","url":null,"abstract":"Equipment such as head-mounted displays are now available for the average consumer at affordable prices. This promotes the usage of this equipment for content consumption and demonstrations, thus it becomes important to establish the best practices for using this technology, namely guidelines in what concerns the recommended exposure time. Therefore, the purpose of this work is to study the impact of the exposure time on the feeling of presence while watching 360° video using an head-mounted display. The independent variables of the study are the exposure time to the stimuli and gender of participants. There were tested four different exposure times: 1 minute, 3 minutes, 5 minutes and 7 minutes. For measuring presence, it was a Portuguese version of the Igroup Presence Questionnaire (IPQ) which considers also 3 presence subscales: spatial presence, realism and involvement. The results have revealed that there are few statistically significant differences for the given exposure times at the level of the sense of presence, apart from spatial presence and realism subscales, which consistently increased with exposure time for male participants and slightly decreased for female ones. Men always needed longer exposure times (> 1 minute) to report the highest scores, while women had the opposite behaviour, frequently reporting maximum scores for the shortest experiences.","PeriodicalId":307741,"journal":{"name":"2016 23° Encontro Português de Computação Gráfica e Interação (EPCGI)","volume":"85 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117263686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 10

Towards automatic non-metric traits analysis on 3D models of skulls 三维颅骨模型的非度量特征自动分析

2016 23° Encontro Português de Computação Gráfica e Interação (EPCGI) Pub Date : 2016-11-01 DOI: 10.1109/EPCGI.2016.7851196

Bruno Andrade, Paulo Dias, Catarina Coelho, João Coelho, D. Navega, S. Wasterlain, M. T. Ferreira, B. Santos

引用次数: 1

2016 23&#xB0; Encontro Portugu&#xEA;s de Computa&#xE7;&#xE3;o Gr&#xE1;fica e Intera&#xE7;&#xE3;o (EPCGI)最新文献

2016 23° Encontro Português de Computação Gráfica e Interação (EPCGI)最新文献