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In museum contexts, it is common to meet logistical limitations that make it difficult to document artworks. The pictorial heritage introduces further challenges due to the nonmodifiability of the lighting setup, which is based on preservation and communication criteria that emphasize the material and execution characteristics of the artwork. This can result in situations that are unsuitable for conducting surveys based on photographic images, which are already complicated by the optical properties of areas covered in gold leaf. The data processing technique described here was developed for the documentation of the Annunciation (1430-32) by Fra Giovanni Angelico (Museo Basilica S. Maria delle Grazie, San Giovanni Valdarno, Arezzo) and it offers the elimination and mitigation of undesirable phenomena due to the specific conditions of the museum context. A strategy capable of removing shadows and chiaroscuro effect from the textures associated with the digital model of the painting and its frame is presented, ensuring its visual reliability. [ABSTRACT FROM AUTHOR]

Tracking the head in a video stream is a common thread seen within computer vision literature, supplying the research community with a large number of challenging and interesting problems. Head pose estimation from monocular cameras is often considered an extended application after the face tracking task has already been performed. This often involves passing the resultant 2D data through a simpler algorithm that best fits the data to a static 3D model to determine the 3D pose estimate. This work describes the 2.5D constrained local model, combining a deformable 3D shape point model with 2D texture information to provide direct estimation of the pose parameters, avoiding the need for additional optimization strategies. It achieves this through an analytical derivation of a Jacobian matrix describing how changes in the parameters of the model create changes in the shape within the image through a full-perspective camera model. In addition, the model has very low computational complexity and can run in real-time on modern mobile devices such as tablets and laptops. The point distribution model of the face is built in a unique way, so as to minimize the effect of changes in facial expressions on the estimated head pose and hence make the solution more robust. Finally, the texture information is trained via local neural fields—a deep learning approach that utilizes small discriminative patches to exploit spatial relationships between the pixels and provide strong peaks at the optimal locations. [ABSTRACT FROM AUTHOR]

Real-time switched networks are becoming popular with the growing complexity of distributed embedded systems. There is a practical need to transmit noncritical data including diagnostic and supervising data for cost reduction. To meet hard real-time constraints, the time-triggered method is widely used due to its deterministic property, where both the reliability of the control data transmission and the tolerance of link failures are required. Conventional methods deploy redundant links and transmit frames over multiple disjoint paths. This paper presents a novel schedule method for the time-triggered network without simultaneous transmissions with multiple frames. The fault tolerance protocol is localized for critical data. We harness multiple effective optimization heuristics and strategies to ameliorate the existing schedule model and constraints. The experimental evaluation substantiates that our effective method can considerably improve the bandwidth for noncritical traffics with no link failures. [ABSTRACT FROM AUTHOR]

Abstract In this study, we investigated analytical challenges associated with the formulation of 2 anti-HIV broadly neutralizing antibodies (bnAbs), 3BNC117 and PGT121, both separately at 100 mg/mL and together at 50 mg/mL each. The bnAb formulations were characterized for relative solubility and conformational stability followed by accelerated and real-time stability studies. Although the bnAbs were stable during 4°C storage, incubation at 40°C differentiated their stability profiles. Specific concentration-dependent aggregation rates at 30°C and 40°C were measured by size exclusion chromatography for the individual bnAbs with the mixture showing intermediate behavior. Interestingly, although the relative ratio of the 2 bnAbs remained constant at 4°C, the ratio of 3BNC117 to PGT121 increased in the dimer that formed during storage at 40°C. A mass spectrometry-based multiattribute method, identified and quantified differences in modifications of the Fab regions for each bnAb within the mixture including clipping, oxidation, deamidation, and isomerization sites. Each bnAb showed slight differences in the levels and sites of lysine residue glycations. Together, these data demonstrate the ability to differentiate degradation products from individual antibodies within the bnAb mixture, and that degradation rates are influenced not only by the individual bnAb concentrations but also by the mixture concentration. [ABSTRACT FROM AUTHOR]

Abstract Here we describe new fluorescent probes based on fluorescein and rhodamine that provide reversible, real-time insight into cellular redox status. The new probes incorporate bio-imaging relevant fluorophores derived from fluorescein and rhodamine linked with stable nitroxide radicals such that they cannot be cleaved, either spontaneously or enzymatically by cellular processes. Overall fluorescence emission is determined by reversible reduction and oxidation, hence the steady state emission intensity reflects the balance between redox potentials of critical redox couples within the cell. The permanent positive charge on the rhodamine-based probes leads to their rapid localisation within mitochondria in cells. Reduction and oxidation also leads to marked changes in the fluorophore lifetime, enabling monitoring by fluorescence lifetime imaging microscopy. Finally, we demonstrate that administration of a methyl ester version of the rhodamine-based probe can be used at concentrations as low as 5 nM to generate a readily detected response to redox stress within cells as analysed by flow cytometry. Graphical abstract fx1 Highlights • New fluorescent probes give reversible real-time insight into cellular redox status. • Probe structure enhances mitochondrial retention. • Reversible fluorescence switch-on predominantly occurs within mitochondria. • Probe reduction, balanced by re-oxidation, controls fluorophore lifetime and emission. [ABSTRACT FROM AUTHOR]

Highlights • An integrated real-time method for the rendering of the infrared characteristics for large-scale terrains. • Infrared characteristics calculation based on the terrain classification of remote-sensing images. • Real-time rendering of multi-resolution infrared texture and terrain pyramids. Abstract As a low-cost, efficient, digital simulation tool, real-time rendering of the infrared characteristics for large-scale terrains is typically interdisciplinary involving the rapid computation of heat transfer and infrared physics models, as well as tools associated with pattern recognition and computer graphics. This paper proposes an integrated real-time method that renders the infrared characteristics of large-scale terrains based on the classification of remote-sensing images in the visible band which can be obtained more conveniently. An energy balance model for terrains composed of different surface materials is established. This model is used in calculating the infrared characteristics of different terrain features and in generating a multi-resolution texture pyramid with the classification information. The infrared calculation results were verified by comparing with results from real world data. Out-of-core rendering method is used to load the mesh data and textures of the large-scale terrains. The process meets real-time demands when rendering terrain composed of over 200 GB mesh data and 15 LOD (level of detail). [ABSTRACT FROM AUTHOR]

Lines are significant features enclosing high-level information in an image. The line segment Detector (LSD) Algorithm with low error rate is a widely used method to extract lines in images effectively and accurately. However, the algorithm on PC performs too costly both in time and resources for the real-time video processing. This paper provides a fast and resource-efficient hardware implementation solution for a modified LSD algorithm on Field Programmable Gate Arrays (FPGA) for real-time line detection. The task-level pipeline structures are exploited fully in a stream process mapped to the hardware architecture free of frame buffer. Our proposed hardware implementation processes in a stream-in–stream-out manner with little consumption of the on-chip block RAM to store intermediate values. We first employ hardware Gaussian filter and adjust Canny edge detection to obtain an edge map at single-pixel width. Then, a novel structure of region growing model based on dynamic rooted tree is used to detect line segment regions accurately with a latency of only a few rows of pixels. The low cost in time, on-chip resources, and power consumption makes our proposed algorithm suitable for portable real-time streaming video processing applications using line segment features, such as Lane departure warning systems. It can also be applied in real-time machine vision systems that use line segments information for further recognition or stereo correspondence and many others. The proposed algorithm is synthesized and tested on XC7Z020 FPGA with high reliability, accuracy speed, and low cost in both resources and energy. [ABSTRACT FROM AUTHOR]

We present an approach for real-time pen-and-ink hatching renderings on large scenes. Starting with 3D models including photorealistic textures and materials, we aim to propose a solution that produces hatched renderings. As we consider scene objects described as polygonal meshes with their own textures, we produce once hatching patterns at different tones and resolutions considering the material of each object. To achieve that, we create a flow direction map per texture pixel, using contour characteristics extracted from the original texture and then interpolated. Stroke trajectories are thus generated depending on the flow direction and using B-splines, providing tones from light-to-dark. Tones are then stored in a mutli-resolution tonal art map. Moreover, we aim to overcome the limitations of existing hatching rendering methods by introducing an illumination model, fully implemented on GPU and able to manage three shading types: regular shadow, soft/cast shadow and self-shadowing. Tones and hatching resolutions are, therefore, assigned according to local/global illumination supporting multiple light sources. Our model, both dedicated for 3D static model renderings and 3D model animation, supports model deformations and is also spatially and temporally coherent since it gives continuous hatching strokes during object animations and/or light displacements. [ABSTRACT FROM AUTHOR]

This paper proposed a new method of seamless terrain rendering based on curve fitting and GPU. It could solve the screen discontinuity problem and the problem of small frame rate in real-time rendering. The algorithm used curve fitting function based on least square method. It could eliminate cracks by controlling the layout of the vertices of the different layers of the grid. This paper constructed resolution-based pyramid model,introducing lossy or lossless compression data at different levels of detail. The algorithm extracted the corresponding data in real-time by the viewpoint prediction. The experiments show that the frame rates are high and the variation of frame rates is small when the large-scale terrain is being rendered,cracks are eliminated efficiently,the rendering is steady. [ABSTRACT FROM AUTHOR]

Quick Response QR barcode detection in nonarbitrary environment is still a challenging task despite many existing applications for finding 2D symbols. The main disadvantage of recent applications for QR code detection is a low performance for rotated and distorted single or multiple symbols in images with variable illumination and presence of noise. In this paper, a particular solution for QR code detection in uncontrolled environments is presented. The proposal consists in recognizing geometrical features of QR code using a binary large object- (BLOB-) based algorithm with subsequent iterative filtering QR symbol position detection patterns that do not require complex processing and training of classifiers frequently used for these purposes. The high precision and speed are achieved by adaptive threshold binarization of integral images. In contrast to well-known scanners, which fail to detect QR code with medium to strong blurring, significant nonuniform illumination, considerable symbol deformations, and noising, the proposed technique provides high recognition rate of 80%–100% with a speed compatible to real-time applications. In particular, speed varies from 200 ms to 800 ms per single or multiple QR code detected simultaneously in images with resolution from 640 × 480 to 4080 × 2720, respectively. [ABSTRACT FROM AUTHOR]

The Internet is the primary means for multimedia content sharing, playing a central role in the lifestyle of users. As a consequence, in the past few years, the traffic demand for access and edge networks has increased (video stream downloading, videoconferencing or even the broadcasting of video streams through the Internet), since multimedia applications have strict requirements, including high bandwidth, small amount of loss and low delay. To address this scenario, the edge as a service (EaaS) paradigm arises as a suitable approach to increasing the quality of Internet access. The EaaS uses network virtualization and software-defined networks to improve the resource utilization and manageability. Within this context, this article proposes a framework to manage the virtual network resource (VNR) according to the multimedia application characteristics, and not only the network requirements. Additionally, a study about the relationship between quality of experience (QoE) and VNR availability was performed to be used as a basis for a proposed resource allocation adjustment mechanism. Experiments using real multimedia traffic under distinct scenarios demonstrate the effectiveness of the proposed framework to ensure the QoE of users through the management of the VNR. [ABSTRACT FROM AUTHOR]

Volumetric shadows often increase the realism of rendered scenes in computer graphics. Typical volumetric shadows techniques do not provide a smooth transition effect in real-time with conservation on crispness of boundaries. This research presents a new technique for generating high quality volumetric shadows by sampling and interpolation. Contrary to conventional ray marching method, which requires extensive time, this proposed technique adopts downsampling in calculating ray marching. Furthermore, light scattering is computed in High Dynamic Range buffer to generate tone mapping. The bilateral interpolation is used along a view rays to smooth transition of volumetric shadows with respect to preserving-edges. In addition, this technique applied a cube shadow map to create multiple shadows. The contribution of this technique isreducing the number of sample points in evaluating light scattering and then introducing bilateral interpolation to improve volumetric shadows. This contribution is done by removing the inherent deficiencies significantly in shadow maps. This technique allows obtaining soft marvelous volumetric shadows, having a good performance and high quality, which show its potential for interactive applications. [ABSTRACT FROM AUTHOR]

This paper presents a direct stylization system to render 3D animated geometry as watercolor painted animation. Featuring low-level art-direction in real-time, our approach focuses on letting users paint custom stylization parameters in the 3D scene. These painted parameters drive watercolor effects in object-space, managing localized control and emulating the characteristic appearance of traditional watercolor. For this purpose, the parameters alter the object-space geometric representations and are rasterized, to coherently control and enhance further image-space effects. The watercolor effects are simulated through improved and novel algorithms to recreate hand tremors, pigment turbulence, color bleeding, edge darkening, paper distortion and granulation. All these represent essential characteristic effects of traditional watercolor. The proposed direct stylization system scales well with scene complexity, can be implemented in most rendering pipelines and can be adapted to simulate a wide range of watercolor looks. The simulation is compared to previous approaches and is evaluated through a user study, involving professional CG artists spending over 50 h stylizing their own assets and sharing their feedback about the watercolor stylization, the direct stylization system and their needs as artists using Non-photorealistic Rendering (NPR). [ABSTRACT FROM AUTHOR]

In traditional 2D animation several intermediate frames are drawn between two consecutive key frames. This process can be very time-consuming and tedious for the animator. In this paper we present a semi-automatic inbetweening method that is tightly coupled with the animation production pipeline. We exploit the fact that artists typically start with an outline of the drawing to help preview the illustration, and use these guidelines to improve the curve correspondence inference. The method is based on a two-level matching algorithm, where the first one finds correspondences between the guidelines, and the second one between the final art. This separation further aids the artist by using transformed guidelines and drawings from preceding frames to guide the creation of new ones, acting as a digital light table. We show the robustness of our method with a variety of animation examples, including sequences from animation books and professional animators. [ABSTRACT FROM AUTHOR]

This paper outlines a digital workflow that allows artists to add visual detail to 3D models whilst adhering to the strict polygonal budget that is vital to successfully render in real-time. Two versions of a model – a high-poly model, and a low-poly model – are produced to create a 2D normal map through a process known as ‘baking’, to achieve the illusion of the high resolution detail on the low-resolution model. [ABSTRACT FROM PUBLISHER]

With increasing numbers of flights worldwide and a continuing rise in airport traffic, air-traffic management is faced with a number of challenges. These include monitoring, reporting, planning, and problem analysis of past and current air traffic, e.g., to identify hotspots, minimize delays, or to optimize sector assignments to air-traffic controllers. To cope with these challenges, cyber worlds can be used for interactive visual analysis and analytical reasoning based on aircraft trajectory data. However, with growing data size and complexity, visualization requires high computational efficiency to process that data within real-time constraints. This paper presents a technique for real-time animated visualization of massive trajectory data. It enables (1) interactive spatio-temporal filtering, (2) generic mapping of trajectory attributes to geometric representations and appearance, and (3) real-time rendering within 3D virtual environments such as virtual 3D airport or 3D city models. Different visualization metaphors can be efficiently built upon this technique such as temporal focus+context, density maps, or overview+detail methods. As a general-purpose visualization technique, it can be applied to general 3D and 3+1D trajectory data, e.g., traffic movement data, geo-referenced networks, or spatio-temporal data, and it supports related visual analytics and data mining tasks within cyber worlds. [ABSTRACT FROM AUTHOR]

In the field of geographic information, fast surface modelling techniques are important. Usually, mesh model is used to describe the terrain. However, the large data of mesh model are a bottleneck of real-time rendering. Compared with the CPU, GPU has more execution units and memory units, which greatly improves its computing capacity and memory bandwidth. Meanwhile, in the field of image rendering, OpenGL has always played an important role. Since CUDA (compute unified device architecture) and OpenGL both run on GPU and share data through common memory, this paper gives a three-dimensional terrain real-time rendering method based on CUDA–OpenGL interoperability. First, we use CUDA C kernel function to calculate the vertex coordinates and normal vectors, then we pass the data to OpenGL buffer, and render it. In this paper, we use share memory and register, overlap strategy, the expansion of concurrency and the reasonable block size. The experimental results show that this algorithm can improve the computing speed greatly, with the speedup to 212.3x, meeting the needs of real-time rendering. [ABSTRACT FROM PUBLISHER]

The primary goal of this study is to create and test a lecture-capture system that can rearrange visual elements while recording is still taking place, in such a way that student performance can be positively influenced. The system we have devised is capable of integrating and rearranging multimedia sources, including learning content, the instructor and students' images, into lecture videos that are embedded in a website for students to review after school. The present study employed a two-group experimental design, with 153 participants (145 females and 8 males) making up an experimental group in which lecture courses were recorded using the new lecture-capture system, and 149 participants (140 females and 9 males) forming a control group whose lectures were recorded by traditional means. All participants were in the freshman college and studying Introduction to Computer and Information Science in one of six classes, and were randomly assigned to one of the two groups. The participants' midterm examination and final examination scores were collected as indicators of their academic performance, with their mathematics entrance scores used as a pre-test. The findings obtained from analysis of covariance (ANCOVA) suggest that appropriate rearrangement of visual elements in lecture videos can significantly impact students' learning performance. [ABSTRACT FROM AUTHOR]

In most realtime applications such as 3D games, in order to reduce the complexity of the scene being rendered, objects are often made by simple and large primitives. Thus, the phenomenon of edge highlighting, which would require chamfering structures made by lots of small patches at the seaming, is absent and is often faked by 'highlights' drawn on the texture. We proposed a realistic realtime rendering procedure for highlighting chamfering structures, or rounded edges, by considering specified edges as thin cylinders and obtained the intensity via integration. We derived a brief approximated formula generalized from Blinn's shadow model, and used a precomputed integration table to accelerate the render speed and reduce resources needed. The algorithm is implemented with shader language, and can be considered as a post-process on original result. Evaluation shows that the effect on rendering speed is limited even for scenes with large scale of vertices. [ABSTRACT FROM AUTHOR]

This paper highlights and addresses the complexity and challenges involved in visualizing large and detailed Building Information Models (BIM) in real-time. The contribution of the paper is twofold: (a) an in-depth analysis of four commonly used BIM viewers in terms of real-time rendering performance and (b) the development and validation of a prototype BIM viewer specifically designed to allow real-time visualization of large and complex building models. Regarding existing BIM viewers our results show that they all share limitations in their ability to handle large BIMs taken from real-world projects interactively. However, for the same test models our prototype BIM viewer is able to provide smooth real-time performance without sacrificing visual accuracy. By taking advantage of an efficient visibility determination algorithm, our prototype viewer restricts rendering efforts to visible objects only, with a significant performance increase compared to existing BIM viewers as a result. [ABSTRACT FROM AUTHOR]

In economy, society and personal life map-based interactive geospatial visualization becomes a natural element of a growing number of applications and systems. The visualization of 3D geospatial information, however, raises the question how to represent the information in an effective way. Considerable research has been done in technology-driven directions in the fields of cartography and computer graphics (e.g., design principles, visualization techniques). Here, non-photorealistic rendering (NPR) represents a promising visualization category - situated between both fields - that offers a large number of degrees for the cartography-oriented visual design of complex 2D and 3D geospatial information for a given application context. Still today, however, specifications and techniques for mapping cartographic design principles to the state-of-the-art rendering pipeline of 3D computer graphics remain to be explored. This paper revisits cartographic design principles for 3D geospatial visualization and introduces an extended 3D semiotic model that complies with the general, interactive visualization pipeline. Based on this model, we propose NPR techniques to interactively synthesize cartographic renditions of basic feature types, such as terrain, water, and buildings. In particular, it includes a novel iconification concept to seamlessly interpolate between photorealistic and cartographic representations of 3D landmarks. Our work concludes with a discussion of open challenges in this field of research, including topics, such as user interaction and evaluation. [ABSTRACT FROM AUTHOR]

This paper presents a real-time animation system for fully embodied virtual humans that satisfies accurate foot placement constraints for different human walking and running styles. Our method offers a fine balance between motion fidelity and character control, and can efficiently animate over sixty agents in real time (25 FPS) and over a hundred characters at 13 FPS. Given a point cloud of reachable support foot configurations extracted from the set of available animation clips, we compute the Delaunay triangulation. At runtime, the triangulation is queried to obtain the simplex containing the next footstep, which is used to compute the barycentric blending weights of the animation clips. Our method synthesizes animations to accurately follow footsteps, and a simple IK solver adjusts small offsets, foot orientation, and handles uneven terrain. To incorporate root velocity fidelity, the method is further extended to include the parametric space of root movement and combine it with footstep based interpolation. The presented method is evaluated on a variety of test cases and error measurements are calculated to offer a quantitative analysis of the results achieved. [ABSTRACT FROM AUTHOR]

Street-level visualization is an important application of 3D city models. Challenges to street-level visualization include the cluttering of buildings due to fine detail and visualization performance. In this paper, a novel method is proposed for street-level visualization based on visual saliency evaluation. The basic idea of the method is to preserve these salient buildings in a scene while removing those that are non-salient. The method can be divided into pre-processing procedures and real-time visualization. The first step in pre-processing is to convert 3D building models at higher Levels of Detail (LoDs) into LoD1 models with simplified ground plans. Then, a number of index viewpoints are created along the streets; these indices refer to both the position and the direction of each street site. A visual saliency value is computed for each building, with respect to the index site, based on a visual difference between the original model and the generalized model. We calculate and evaluate three methods for visual saliency: local difference, global difference and minimum projection area. The real-time visualization process begins by mapping the observer to its closest indices. The street view is then generated based on the building information stored in those indexes. A user study shows that the local visual saliency method performs better than do the global visual saliency, area and image-based methods and that the framework proposed in this paper may improve the performance of 3D visualization. [ABSTRACT FROM AUTHOR]

Triggered by the development of new hardware, such as laser range scanners for high resolution acquisition of complex geometric objects, new graphics processors for realtime rendering and animation of extremely detailed geometric structures, and novel rapid prototyping equip-ment, such as 3D printers, the processing of highly resolved complex geometries has established itself as an important area of both fundamental research and impressive applications. Concepts from image processing have been picked up and carried over to curved surfaces, physically based modeling plays a central role, and aspects of computer aided geometry design have been incorporated. This paper aims at highlighting some of these developments, with a particular focus on methods related to the mechanics of thin elastic surfaces. We provide an overview of different geometric representations ranging from polyhedral surfaces over level sets to subdivision surfaces. Furthermore, with an eye on differential-geometric concepts underlying continuum mechanics, we discuss fundamental computational tasks, such as surface flows and fairing, surface deformation and matching, physical simulations, as well as spectral and modal methods in geometry processing. Finally, beyond focusing on single shapes, we describe how spaces of shapes can be investigated using concepts from Riemannian geometry. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Indirect Illumination is a key element to achieve realistic rendering. Unfortunately, since computing this effect is costly, there are few methods that render it with real-time frame rates. In this paper we present a new method based on virtual point lights and topological information about the scene to render indirect illumination in real-time. [ABSTRACT FROM AUTHOR]

One of the problems in virtual globes technologies is the real-time representation of vegetal species. In forest or garden representations, the low detailed plants produce a lack of realism. Efficient techniques are required to achieve accurate interactive visualisation due to the great number of polygons the vegetal species have. This article presents a multi-resolution model based on a geometric representation of vegetal species that allows the application to perform the progressive transmission of the model, that is, the transmission of a simple representation followed by successive refinements of it. It has a hardware-oriented design in order to obtain interactive frame rates. The geometric data of the objects are stored in the graphics processing unit and, moreover, the change from one approximation to another is obtained by performing mathematical calculations in this graphics hardware. The multi-resolution model presented here enables instancing: as many vegetal species as desired can be rendered with different levels of detail, while all of them are accessing the same geometric data. This model has been used to build a real-time representation of a not imaginary scenario. [ABSTRACT FROM AUTHOR]

Modern handheld devices can act as “magic lenses” for public displays and enable camera-based real-time interaction with their contents, thus allowing for manifold interactive applications in public space. To learn more about the characteristics of common techniques and to provide guidelines for new ones, a comparative user study was conducted. With regard to two basic task types (selection and translation) and two typical devices (smartphone and tablet), three interaction techniques in-depth were evaluated: direct touch-based input (Touch), cross-hair targeting (Target), and a new technique based on a dynamic cross-hair on the screen that snaps to visible nearby screen objects (Snap Target). The study results indicate that successful interaction with the Touch technique strongly depends on the usage context: Although Touch enables fast selection, it incurs many errors when small targets have to be selected on a smartphone. Target supports such difficult selections better, but Snap Target proved to be most robust in both investigated task types. Also, users stated that they felt best supported by the latter technique. Cross-hair-based techniques, especially Snap Target, were found to be well suitable for scenarios where several device types need to be supported under similar conditions. Implications and further work are discussed. [ABSTRACT FROM PUBLISHER]

Interactive product presentation techniques have recently gained importance in online marketing of house products. Real-time simulation offers a high level interactive presentation with more powerful features to present product functions and variations. This article presents a novel computational approach for engaging and supporting consumers in making informed choices about purchasing house products. It involved the development and testing of an online interactive real-time simulation for house product marketing (the Virtual House Showroom-VHS). This model also included optional humanoid avatars, representing a virtual buyer-seller experience. The research assessed the effectiveness of the VHS on consumers' cognitive and affective responses. In particular, it examined whether consumers' responses to real-time simulation with a humanoid avatar are significantly different from their responses to the model without the avatar. Participants (n = 110) were organized into two groups. Group 1 (n = 56) evaluated VHS without the humanoid avatar and group 2 (n = 54) appraised the model with the avatar. The results confirmed that interactive online real-time simulation technologies without the avatar have significant effects on consumers' cognitive learning, affect, and behavior. However, it was found that the humanoid avatar had no significant effect on respondents' decision-making. Further research was suggested to improve the usability of real-time simulation in the marketing of house products. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we present a simplified 3D particle system and fast translation algorithm we have designed and implemented to generate real-time animated particle emitter fountains choreographed by a classical music. The approach we used to translate and map the controlling information into the musical fountain animation is also introduced, as well as the process to build the physical model of the music fountains. A proof of concept is implemented to demonstrate the main system's aspects, its feasibility, and that it has met the system's design goals. Moreover, it shows that is possible to observe visual patterns that match the theme of the musical composition, as an example of how the system can be used not only for visual appreciation and entertainment, but also as a possible support tool for music composition. We have also conducted a user study as an evaluation of the system. The results of this have provided us with positive and useful feedback on the effectiveness of our visual mappings as well as further directions to explore. [Copyright &y& Elsevier]

Every picture tells a story. In photography, the story is portrayed by a composition of objects, commonly referred to as the subjects of the piece. Were we to remove these objects, the story would be lost. When manipulating images, either for artistic rendering or cropping, it is crucial that the story of the piece remains intact. As a result, the knowledge of the location of these prominent objects is essential. We propose an approach for saliency detection that combines previously suggested patch distinctness with an object probability map. The object probability map infers the most probable locations of the subjects of the photograph according to highly distinct salient cues. The benefits of the proposed approach are demonstrated through state-of-the-art results on common data sets. We further show the benefit of our method in various manipulations of real-world photographs while preserving their meaning. [ABSTRACT FROM AUTHOR]

In this paper, an efficient deformation framework is presented for skeleton-driven polygonal characters. Standard solutions, such as linear blend skinning, focus on primary deformations and require intensive user adjustment. We propose constructing a lattice of cubic cells embracing the input surface mesh. Based on the lattice, our system automatically propagates smooth skinning weights from bones to drive the surface primary deformation, and it rectifies the over-compressed regions by volume preservation. The secondary deformation is, in the meanwhile, generated by the lattice shape matching with dynamic particles. The proposed framework can generate both low- and high-frequency surface motions such as muscle deformation and vibrations with few user interventions. Our results demonstrate that the proposed lattice-based method is liable to GPU computation, and it is adequate to real-time character animation. [ABSTRACT FROM AUTHOR]

PhotoCloud is a real-time client-server system for interactive visualization and exploration of large datasets comprising thousands of calibrated 2D photographs of a scene and a complex 3D description of the scene. The system isn't tailored to any specific data acquisition process; it aims at generality and flexibility. PhotoCloud achieves scalability through a multiresolution dynamic hierarchical representation of the data, which is remotely stored and accessed by the client through an efficient cache system. The system includes a compact image browser and a multiresolution model renderer. PhotoCloud employs iconic visualization of the images in the 3D space and projects images onto the 3D scene on the fly. Users can navigate the 2D and 3D spaces with smooth, integrated, seamless transitions between them. A study with differently skilled users confirms PhotoCloud's effectiveness and communication power. The Web extras at http://www.youtube.com/playlist?list=PLHJB2bhmgB7cmYD0ST9CEDMRv1JlX4xPH are videos demonstrating PhotoCloud, a real-time client-server system for interactive exploration of large datasets comprising 2D photos and 3D models. [ABSTRACT FROM PUBLISHER]

Date hub proteins have 1 or 2 interaction interfaces but many interaction partners. This raises the question of whether all partner proteins compete for the interaction interface of the hub or if the cell carefully regulates aspects of this process? Here, we have used real-time rendering of protein interaction networks to analyse the interactions of all the 1 or 2 interface hubs of Saccharomyces cerevisiae during the cell cycle. By integrating previously determined structural and gene expression data, and visually hiding the nodes (proteins) and their edges (interactions) during their troughs of expression, we predict when interactions of hubs and their partners are likely to exist. This revealed that 20 out of all 36 one- or two- interface hubs in the yeast interactome fell within two main groups. The first was dynamic hubs with static partners, which can be considered as 'competitive hubs'. Their interaction partners will compete for the interaction interface of the hub and the success of any interaction will be dictated by the kinetics of interaction (abundance and affinity) and subcellular localisation. The second was static hubs with dynamic partners, which we term 'non-competitive hubs'. Regulatory mechanisms are finely tuned to lessen the presence and/or effects of competition between the interaction partners of the hub. It is possible that these regulatory processes may also be used by the cell for the regulation of other, non-cell cycle processes. [ABSTRACT FROM AUTHOR]

Image scaling is an important technique that is widely used in many image processing applications. This paper presents a novel scaling algorithm for the implementation of 2-D image scalar. The proposed interpolation method is based on the interpolation error theorem often mentioned in numerical analysis. A bilateral error-amender is used to make the interpolation more precise, and an edge-weighted scheme enhances the edge features of the scaled images. Extensive experimental results demonstrate that the proposed method can obtain better performance than previous methods in both quantitative evaluation and visual quality. This paper also presents an efficient very large-scale integrated architecture for the proposed method. The cooperation and hardware sharing techniques greatly reduce hardware cost requirements. Using a nine-stage pipeline, the proposed scaling circuit contains 13 k gate counts and yields a processing rate of approximately 278 MHz using TSMC 0.13-\mum technology. The hardware cost of the proposed circuit is low, making it a good candidate for high-quality image scaling applications. [ABSTRACT FROM PUBLISHER]

Along with the development of new technologies, orchestrating computer-supported collaborative learning (CSCL) has become a topic of discussion because new learning spaces challenge teacher to support collaborative learning in new ways. However, despite the optimistic notions of teachers’ orchestration in CSCL situations, there are still no systematic research findings on real-time orchestration. This study is one attempt to fill in the knowledge gap on understanding the differences in knowledge construction processes between settings with and without teachers’ real-time orchestration in 3D learning games from a socio-cultural perspective. The aims of the study are twofold. The first aim is to design a scripted 3D learning game to practice inter-professional knowledge construction in a vocational context. The second goal is to determine the main differences in knowledge construction processes in 3D game settings with and without real-time teacher orchestration. Findings provide new insights into what actually happens in collaboration processes within different learning settings. Specifically, students in settings with real-time teacher orchestration used more effort to provide knowledge (especially explaining one’s own situation) and less effort for other inputs (in particular, off task discussion). Thus, a scripted 3D game itself guided and helped groups to solve tasks. However, teachers’ professional competencies also helped to reduce off task discussions during the 3D game, develop a shared understanding of the tasks’ inter-professional nature, and explain activities in a meaningful way. [Copyright &y& Elsevier]

Polluted water is very common in our world. Vividly rendering polluted water can bring people real, different, and fancy feelings. Especially in under water imagery, taking polluted water into consideration will produce more plausible results. Polluted water consists of many kinds of pollutants, which interact with light differently and make water look turbid. The optical properties of polluted water change with the concentrations of pollutants significantly. In this paper, we provide a method to obtain the optical properties of polluted water, which makes a bio-optical model for polluted water and connects the optical parameters with water quality data, i.e., the concentrations of pollutants. Our method can estimate the optical properties of polluted water regardless of the kinds and the concentrations of pollutants in water. Polluted water is inhomogeneous and has multiple scattering effects. We use volumetric photon mapping to render it and provide a 3D weight-varying radiance estimate method for the photon mapping. This radiance estimate method can compute high-frequency effects easily, which can show more details of the pollution process. Experiments demonstrate that our approach can generate polluted water effects unachievable by standard rendering methods. [ABSTRACT FROM AUTHOR]

Light baking has long been a popular technique for real-time rendering. It usually precomputes and bakes the global lighting effects as vertex attributes or textures. Vertex baking requires less memory but can cause artifacts for large triangles. Texture baking can avoid this and generate a high-quality visual effect in real-time rendering. However, it requires significant memory consumption, which may limit the real-time performance and usage. To address this problem, we propose an adaptive mesh subdivision algorithm for memory-efficient light baking, including a fast triangle subdivision level determination method and an optimized solution to calculate vertex colors. Only the subdivided mesh is required during the real-time rendering. Therefore, memory requirements can be significantly reduced while keeping the visual effect. Besides, the subdivision level is allowed to be intuitively controlled by users with a specified parameter. Our algorithm can be easily implemented on commodity graphics hardware and integrated in existing real-time applications such as online preview systems. [ABSTRACT FROM AUTHOR]

Maximum Intensity Difference Accumulation (MIDA) combines the advantage of Direct Volume Rendering (DVR) and Maximum Intensity Projection (MIP). However, many features with local maximum intensity are still missing in the final rendering image. This paper presents a novel approach to focus on features with local maximum intensity within the dataset. Moving Least Squares (MLS) is used to smooth each ray profile during the raycasting in order to eliminate noise in the data and to highlight significant transition points on the profile. We then adopt a local minimum-point searching method to analyze the ray profile, and identify the transition points that mark the local maximum intensity points within the dataset. At the rendering stage, we implement a novel local intensity difference accumulation (LIDA) to accumulate the colors and opacity. Surface shading is introduced to improve the spatial cues of the features. We also employ tone-reduction to preserve the original local contrast. Our approach can highlight local features in the dataset without involving the adjustment of transfer functions. The experiments demonstrate high-quality rendering results at an interactive frame rate. [ABSTRACT FROM AUTHOR]

Large-scale remote sensing images, including both satellite and aerial photographs, are widely used to render terrain scenes in real-time geographic visualization systems. Such systems often require large memories in order to store fine terrain details and fast network speeds to transfer image data, if they are built as web applications. In this paper, we propose a progressive texture compression framework to reduce the memory and bandwidth cost by compressing repeated content within and among large-scale remote sensing images. Different from existing image factorization methods, our algorithm incrementally find similar regions in new images so that large-scale images can be more efficiently compressed over time. We further propose a descriptor, the Gray Split Rotate (GSR) descriptor, to accelerate the similarity search. The reconstruction quality is finally improved by compressing residual error maps using customized S3TC-like compression. Our experiment shows that even with the error maps, our system still has higher compression rate and higher compression quality than using S3TC alone, which is a typical compression solution in most existing visualization systems. [ABSTRACT FROM AUTHOR]

Rendering global illumination for objects with mesostructure surfaces is a time-consuming task, and cannot presently be applied to interactive graphics. This paper presents a real-time rendering method based on a mesostructure height gradient map (MHGM) to exhibit lighting effects on meso-scale details in dynamic environments. We approximate global illumination using a lighting model including three components: incident ambient light, direct light and single bounce indirect light. MHGM is introduced to create local apex sets, which would help us to compute the three components adaptively. Our approach runs entirely on the graphics hardware, and uses deferred shading and the graphics pipeline to accelerate computation. We achieve high quality results which can render meso-scale details with approximate global illumination even for low-resolution geometric models. Moreover, our approach fully supports dynamic scenes and deformable objects. [ABSTRACT FROM AUTHOR]

This paper presents an implementation of the Active Appearance Model that is able to track a face on a mobile device in real-time. We achieve this performance by discarding an explicit texture model, using fixed-point arithmetic for much of the computation, applying a sequence of models with increasing complexity, and exploiting a sparse basis projection via Haar-like features. Our results show that the Haar-like feature basis achieves similar performance to more traditional approaches while being more suitable for a mobile device. Finally, we discuss mobile applications of the system such as face verification, teleconferencing and human-computer interaction. [ABSTRACT FROM AUTHOR]

This paper revisits the problem of wireframe rendering, which, at first, appears to be an easily solved problem. However, the conventional solution is inefficient and does not result in high-quality images. Recently, graphics hardware programming has been employed to achieve high-quality solid line rendering. In this paper, we present a simpler and faster technique for wireframe rendering based on texture mapping. Our technique does not require (but can benefit from) graphics hardware programming and thus can be easily integrated into existing rendering engines, while resulting in fast, accurate, high-quality, anti-aliased, and still versatile, wireframe drawing. For topologically structured meshes, our approach allows the rendering of wireframe decoupled from the underlying mesh, making possible the rendering of original wireframes on top of decimated meshes. [ABSTRACT FROM AUTHOR]

Texture mapping is an important technique for adding visual details to geometric models. Image-based texture mapping is the most popular approach, but it relies on pre-computed images which often limit their use to static effects. For adding dynamic effects, procedural-based texturing is more adequate. Since it rely on functions to describe texturing patterns, procedural texturing allows for a more compact representation and control of visual effects by a simple change of parameters. In this work we describe GeoTextures, an approach that uses geodesic distance fields defined from multiple sources at different locations over a model surface to place, advect, and combine procedural visual effects over complex surfaces. The use of geodesics extends the scope of common procedural textures which are usually limited to using spatial 3D coordinates or 2D texture coordinates. We illustrate the flexibility of our real-time approach with a range of visual effects, such as time-based propagation of weathering phenomena, transparency effects, and mesh displacement over surfaces with smooth silhouettes using hardware based tessellation available in current graphics cards. [ABSTRACT FROM AUTHOR]

Non-photorealistic (illustrative) rendering augments typical rendering models to selectively emphasize or de-emphasize specific structures of rendered objects. Illustrative techniques may affect not only the rendering style of specific portions of an object but also their visibility, ensuring that less important regions do not occlude more important ones. Cutaway views completely remove occluding, unimportant structures-possibly also removing valuable context information-while existing solutions for smooth reduction of occlusion based on importance lack precise visibility control, simplicity and generality. We introduce a new front-to-back fragment composition equation that directly takes into account a measure of sample importance and allows smooth and precise importance-based visibility control. We demonstrate the generality of our composition equation with several illustrative effects, which were obtained by using a set of importance measures calculated on the fly or defined by the user. The presented composition method is suitable for direct volume rendering as well as rendering of layered 3D models. We discuss both cases and show examples, though focusing mainly on illustration of volumetric data. [ABSTRACT FROM AUTHOR]

The objective of this paper is to adapt photon mapping for real-time simulation of caustics. High-performance algorithm adapted for the GPU and implemented on the basis of cross-platform OpenGL and OpenCL APIs is proposed. For effective rendering of caustics and generation of photon map OpenGL shaders are used. Voxel acceleration structure constructed directly on the GPU by means of OpenCL provides fast access to photon map. Performance estimation for different equipment is given. [ABSTRACT FROM AUTHOR]

This work presents an approach for biased photorealistic rendering on graphics processor units (GPUs). The key idea of the approach is to combine irradiance caching with coherent adaptive path tracing. [ABSTRACT FROM AUTHOR]

Abstract: Multi-resolution techniques are required for rendering large volumetric datasets exceeding the size of the graphics card''s memory or even the main memory. The cut through the multi-resolution volume representation is defined by selection criteria based on error metrics. For GPU-based volume rendering, this cut has to fit into the graphics card''s memory and needs to be continuously updated due to the interaction with the volume such as changing the area of interest, the transfer function or the viewpoint. We introduce a greedy cut update algorithm based on split-and-collapse operations for updating the cut on a frame-to-frame basis. This approach is guided by a global data-based metric based on the distortion of classified voxel data, and it takes into account a limited download budget for transferring data from main memory into the graphics card to avoid large frame rate variations. Our out-of-core support for handling very large volumes also makes use of split-and-collapse operations to generate an extended cut in the main memory. Finally, we introduce an optimal polynomial-time cut update algorithm, which maximizes the error reduction between consecutive frames. This algorithm is used to verify how close to the optimum our greedy split-and-collapse algorithm performs. [Copyright &y& Elsevier]

Abstract: The main problem in the real-time rendering of vegetation is the massive amount of primitives to be rendered. These primitives are needed to fully describe the geometry of the plants. However, some of them are not visible depending on the location of the viewer. This work focuses on this fact to interactively reduce the amount of geometry needed to represent the foliage through a view-dependent multiresolution scheme. Following a camera-dependent criterion, the less visible parts of the foliage are detected in real time, and rendered with a decreased level of detail for improving efficiency. This fact considerably reduces the extraction and the visualization time of the geometry that represents the foliage. The novelty of the presented method is that its design is oriented to being efficient on massively parallel architectures, such as the graphics processing unit. Moreover, we introduce a new management system for efficiently handling level of detail objects in order to improve performance for forest scenes. [Copyright &y& Elsevier]